cool video! One small trick, not sure if it is already mentioned here: measure the pin size with calipers, now *zero the caliper*, then measure the outside distance between pins - it'll give you the exact distance between pins.
I managed to print a 50 cm replacement oven door handle, and I had kept the old aluminium face. The face had a lip (perpendicular to the face) and a rounded bevel. I designed the handle with zero clearance for the lip, a matching radius, a groove of the exact width and depth.. It was my first 3d print on my first 3d printer (say .. project larger than a few cm), and it worked as expected. The aluminium face fits nicely in the handle... I used PLA, a 60C heated bed all the time (9 hours), a nice and big raft, and the printer is a Creality CR10 Max, 0.4mm nozzle, 70mm/s. My only complaint is that there is a 0.1 mm deflection over the 50cm of the handle, other than that, I'm happy with the result.
Just so you guys know if you are using PLA and your parts are slightly to big (or your holes are slightly too small) your issue may be solved by increasing your horizontal expansion offset. Basically the PLA is expanding just a little bit due to the heat of melting it, so your parts will be just a little to big. The horizontal expansion offset can help fix this. You will need to do multiple tests seeing what value works best for you.
@@Kz1nk Yes, it was. I played with it and it solved a long standing problem. My XY movement is calibrated based on distance moved but parts were never the exact set sizes. After using XY Compensation they come out very close (0.02 to 0.04mm) to the defined size. Thanks again.
For precise features, we usually CAD those features in a very thin, quick, proto print to get them accurate. Then the full size part. This saves lots of iterative printing time and waste material. Also for threads, snap fits, flex fits, and anything that fits something from "the real world" or even another printer.
Holy cow. I'm very new to 3d printing, only actually printing about a dozen things. They were always too small, and since all of this is new to me, and there is a plethera of new terminology, I've been scouring the interwebs trying to figure out why. I thought my printer was either broke, or there was some calibration sequence I needed to do. I had basically given up, frustrated that I had to manually model everything larger to compensate, since I had no idea what was wrong. And then youtube dropped this in my lap. Thanks so much for taking the time to make this. No overly complicated terminology and a very simple solution. You saved my sanity! I hope your tester came out well!
Great video. Just pulled my old Tarantulas printer out printed an insulated spacer had almost exact errors you had. Your video confirmed my method I was about to do this morning. I am electronic designer by trade, worked with lots good machinist over the years each taught me real world solutions just like this video series. Big thank you.
Love the “to my calibrated eye” ! I use that all the time. Nice clear and thorough explication of the shrinkage problem and how to fix it. I just bought a FDM printer and learning how to use it and that is an issue I have run up against. Thanks for the great video!
It would be great if you could do a similar video, showing the full process of calibrating the printer for accurate dimensions and setup of Simplify 3D. Your way of explaining things is really good.
I think the point of this video was to get a really accurate part with out touching your "already calibrated" printer. Because let's face it, all part behave differently and calibrating the printer for each part is quite annoying/time consuming. I am sure you found that out yourself anyways.
Very interesting. I suppose the shrinkage changes based on the thickness and shape . . . . . if it were directly proportional, no matter what, printing a set of 12" "rulers with very fine scale marked, then compare to actual ruler and maybe that would tell you whether the shrinkage happens across the scale, or jsut in certain parts?. Love your videos, and the Fusion 360 has been far more useful than what pertain to be F360 tutorials. You make it far clearer than those other guys! Thanks!
in the beginning i thought, that you didn't calibrate your axis correct, but your solution and description are GREAT... a new aspect to improve my parts. thx ;) hope that the software desire not too much manual changes in settings when changing filament OR temp! automatic part-enlargement should be mandatory for filament-settings ... NOT after importing, but BEFORE PRINTING!
Thank you for sharing your experience with us and I really enjoyed the video presentation. It showed me how one should go about dealing with shrinkage. Things that I noticed and hope you will continue to do include: You don't assume too much of the experience or knowledge of your audience which I think is great. You disclosed brand names of what you used (filament, 3D program, 3D slicer, spreadsheet, etc.) which I liked. It gives me ideas on how I can use them more effectively or in my environment. Your spreadsheet usage was particular interesting to me. You scripting of your video was well done in that you presented what you wanted to do, demonstrated the problem (with lots of visual close up shots) on what happened, how you identified the problem, the possible solutions and the final solution that you settled on. I thought that a visual inspection of the 3D object would have suggested that the problem was not in the hardware (i.e. 3D printer) but somewhere else since the printed object looked pretty good. But I do commend you for doing your 'due diligence' to make sure that you didn't miss anything as part of your problem analyze segment. As a side note, I thought that if I were looking for the actual shrinkage value due to the equipment & material, I would print the largest diameter rectangle that my printer to produce and measure the resultant print. The deviation between designed & actual dimension would be the most accurate. But back to the video. The pacing was sometimes fast, especially when not familiar with the application or situation but I was able to follow it. The video presentation was professionally done, with great video framing & sound reproduction. Thank you especially for taking the time to do a great presentation. Finally, I do want you to know that I appreciate the time & effort that you put in producing the video and encourage you to continue to do so. Take care and stay safe, Pat Young
Nice example. Thanks for taking the time to show that. Using Siemens NX, I like to add manufacturing specific features like this at the end of the model history, and place these features in a named feature group. That way I model the part as it should be, and then have a group of features for 3D printing (or other manufacturing process) that can be suppressed or unsuppressed as a group. For example, I might enlarge holes slightly based on inaccuracy of the 3D print. Scaling the final part for shrinkage would be a feature in the feature group.
Husband Richard saw you on wife's phone and I subscribed cuse I love to build and design and create .you video was helpful to me with your concise explaining I could understand perfectly. Now I will remember shrinkage. Every now and than I will reach out to you with 3d print solving for help. Very well done 👏
I am a photographer. I still use the old 4X5 field cameras. Last year I bought an MPP MK VII technical field camera for landscape photography. It came with one lens board of Copal 1 size. This camera has not been produced since the early 70s so, instead of paying silly prices for battered old lensboards off the Bay, I decided to 3D print them using a CF infused PLA. I ran exactly into the same problem as you just did. Both trial size No 0 and No1 boards came out undersized. I had to adjust the printing sizes in Cura by quite a bit , around 1% mark If my memory serves me right, to get the lens flange to fit the holes and the retaining nut fit in. I am not quite 100% sure if the quoted filament sizes are accurate or not either.
You can change to a Z up orientation in Fusion 360 by clicking on your name in the upper right and selecting "preferences". In the general tab look for "default modeling orientation" and change it from "Y up" to "Z up"
YES, finally someone who is using 3d printing for engineering purposes. Altho I'm looking for DLP tips, this came very handy for those mucked up designs :)
Wow this explains so much. I've ALWAYS had an issue with things being printed a little undersized and I've been 3D printing for 7 years now. I figured it was just my crappy old printer. I've been setting my prints to 101% or 102% for a long time, but great to know the reason now.
To other viewers: Before you assume that it's your filament material that's shrinking, print some lines that are a known distance apart *but not connected to each other* and check the dimensional accuracy between them. That way you'll factor out the shrinkage and see the true dimensional accuracy of your printer while the parts (the lines) are still stuck to the print bed.
This can be very hard to do accurately, since the differences we care about are small, and layers near the bed are often distorted. I would prefer to measure the actual movement of the printer axes with a caliper or dial indicator.
Could be underextrusion because of constant in extruder or nozzle diameter, also, bed testing isn't the best idea. It's that first layer that is either squished to ensure great adhesion or with offset for easier removal which add a bias factor in consideration.
@@Clough42 The way I tend to do this is by printing an L-shape with equal length legs and square holes at the ends and intersection of the legs. Say the L-shape has 120mm legs, each 20mm wide. There are three 10mm square holes, each with their centre lines 100mm apart. To get the correct axis scale, I measure the internal size of one such hole and zero my calipers on that dimension. Subsequent inside measurement of the holes' furthest sides (in this case 110mm) will show the pitch of the holes' centres. This way all factors involving extrusion width are eliminated, leaving just the actual printed dimension*. The hole sizes can also be averaged, of course, but I've found this to give me rather excellent accuracy in my prints, yielding running fits or press fits wherever I see (wait for it) fit. I take it you choose the print scaling over a permanent firmware scaling of your axes as a material-specific compensation? (* source: moi, being a B.Eng. in mechanical precision engineering 😁)
So that explains that😂 learning as I go along, but was disappointed with why my perfectly designed part was too tight in the real world. And now I know! Thanks for a great lesson!
Nice and succinct explanation. I've run into a similar issue and hadn't considered material shrinkage despite ruling out the same mechanical factors. My error is of the same magnitude hence my new suspicion of material shrinkage. Thanks 👍
Yeah, @ThisOldTony just did a video on how bought a new milling machine, I mean fräsemachine, had weird axis labels. They appear to match default fusion 360. I’ve always been taught if you’re facing the machine, x is starboard to port, y is aft to fore, and z is below to above. Making the back, bottom, left, 0,0,0.
@@areospike1600 I believe his model was based on a horizontal originally so the spindle axis (Z) would be what we'd consider Y. Why they kept the scheme is confusing though.
My ender 3 has sat for 5 months.... been moved... cats walk across it...i finally started printing again and printed 10mm and 20mm test cube, without leveling my bed, just cleaning the glass, and my parts came out .02mm off. Not too damn bad. Printed a print in place box with attached hinged lid... and i didn't even have BREAK free the hinge, it rotated right away. Love it.
I got around a lot of these issues by building all my models in metric. I've not had any issues with size or accuracy since. I live in Ohio, but having worked for a few European based companies in my life, I've had to learn metric. Best thing ever, and never thought it would come in handy. But I use this at work and at home for the printers and designing in metric has helped SO much. Give it a shot!!
Changing the measuring unit does nothing to address shrinkage between the software model and the printed part. As long as your design maintains a consistent system of units you're fine no matter what system you use.
@@mystixa I mean, given I've had the issue and made the correction and have physically held the correct result in my hand.... Sure.... I'll go with your suggestion..... :/
@@That_guy_Pip One has nothing to do with the other. I wasn't suggesting anything other than maintaining a consistent set of units when measuring. It doesn't matter if you call them xblocks or furlongs as long as your measurements remain self consistent.
awesome! I found this as well with fitting a circuit board. You are the only one on the internet with the right fix. I spent a lot of time going down the wrong rabbit holes lol. subscribed!
To get the maximum precision, you should print a test piece at the largest size possible, that way, the shrinkage will be amplified making it easier to measure.
I just watched the same type of video on ItsMeaDMaDe and both were informative and I enjoyed watching them both. I really like how in-depth you get in all of your videos. Thanks for sharing
Great info video, thank you. The only thing I can think of since the slicer allows one setting at a time, is to just print a chart with the shrink rate of each filament material used. When imported into slicer, double click and change parameters accordingly before printing.
It really depends on what you're doing. In my case, most of what I do that requires precise dimensions is in ABS, so one setting gets me close enough. If I routinely required precision in lots of different materials, it would be necessary to do exactly what you describe.
@@Clough42 yep, that is all I was referring to, so I hope you didn't take it like I wanted to help you out. You're way ahead of me, I only commented for viewers who might (for whatever reason) used a variety of materials. For me, probably PLA.
This may be late, but wouldn't you scale by the reciprocal of the part scale (e.g., to account for a shrinkage of 25% that would result in a part at 75%, you would scale by 1/0.75=1.333...)
Been 3d printing now for 3 years and still have been doing the scaling manually on simplify3d. Thankw for making my 3d printing life much simpler. I do a lot of mechanical parts so this helps a lot.
What happens when you use a different filament or printer? Are you going to keep track of what you scaled each and every part with? So your method is actually the preferred method.
Talk about building "fact on fact"; YOU James would make an unbelievable detective. Oh yes you would be indeed. In my 87 yrs on this earth, it would be difficult to find any one that is as brilliant as you are. You are truly a "gifted" man (Praise Jesus) dear sir! We can't wait for each new video you produce. Keep it up.
Thank You! Mind Blown! Once my 3D Skill Level is ready for action, I'm gonna make some super custom sewing machine presser foot attachments (to help glide over stubborn fabrics). Schooling us that the ABS 3D Printer filamint will shrink a bit after it's cooled greatly reduces my shock expectancy of my first printed piece.
I use Prusa Slicer but think this may be applicable to it as well and may explain some of the fit problems I have seen. Also have found that the way I set up the walls makes a difference. Printing the outside of wall first or last to compensate for extrusion squish.
That's cool. I don't use ABS much, mainly because of the warping issues. As such, I wasn't considering, and should have!, that your part shrunk. I thought it was a belt, or estep issue. My thought would be to confirm this using some digital calipers as DRO's on the x and y carriage. My first printer ever was semi-scratch build off of a Shapeoko 2. I was able to use digital calipers to show pretty accurately, and with some precision, X and Y movements, to really tune my esteps. Cool video, as usual! Thank you James!
The pitch of the GT2 belt is actually only valid for a particular specified belt tension. If the tension is wrong, the pitch is wrong, because it does stretch by quite a bit! Well then again that's my experience and i use Chinese parts and not Gates belt. But its easy to check, you tape your calipers down under the nozzle when it's close to the bed, jog the head a bit via controls, zero the caliper, and then have the print head walk a known distance and compare. It's probably pretty close, not enough to make up that difference. The claimed 0.8% shrinkage for standard ABS is significantly less than what i've seen myself, i expect closer to 1.2% shrinkage. I think they have a measurement method which is very kind to shrinkage number. But any figure is a rough guideline since shrinkage is non-uniform depending on shape.
From the moment I read the claim of 0.4% shrinkage, I assumed my results would be a little worse. They're definitely not going to publish the worst-case scenario in the marketing literature.
@@nirodper You might be surprised, often times when the print shrinks, the XY shrink but Z expands a little - just a little! Something about molecule orientation, you can imagine them as springs, you lay them out predominantly lengthwise along your extrusion direction, and when you release and cool down the print, they shrink down; but the material still has to go somewhere. The print shrinkage is not merely or predominantly thermal shrinkage, as you can see, say PETG has no print shrinkage whatsoever.
Very nice. I know that Kira can let you specify the dollar amount of a roll of filament and then perform the calculations to tell you how much your part costs in filament. But I haven't looked at any additional filament just settings. Really enjoyed your video. It's about time that silly algorithm got around to presenting it to me. I was searching for horizontal expansion on RUclips. What I really want to do is tune the machine. Thanks so much.
Now this is what I love about this channel, you just know that when James does something...he does it right! Yet another great video James, keep it up mate! 👍👍👍
You can edit your process settings and set a profile for each type of material you want to use. Then on each profile under the Other tab set the Horizontal Size Compensation appropriately for that material
I noticed that your 3D printer X axis is using a belt, use same config as Z axis material but also a solid coupler not the one looking like spring. This should fix it. Your videos are awesome, thanks for sharing.
In the metal casting world, a common tool used is a shrink rule, each graduated for a specific material with a known percentage of dimensional increase, so that a casting model made using the correct rule for that material will result in a cast part of that material which is the desired final size.
So that means “what you want” finished, is, design scaled - plus oversize for 3D printing - plus - oversize for metal shrinking (using the 3D printed part for loss casting) - and - oversized again for subtractive machining. Not only does SIZE matter, but at X4. And at different values for each type process. (Not even getting into the whole SAE/Decimal/Metric conversation thing...OR rounding up/down) I love it.
The same thing is done in dental lab work. The wax shrinks a known amount. The metal does too. The investment expands a known amount to compensate for the combined shrinkage
Don't have a 3D printer yet, but this was educational as someday one will be making its way home with me and it's good to have a heads up regarding print issues that one can experience.
filament temp also matters. I use mostly PLA, and if I run it at 190 vs. 200 for the one I use for instance, it prints more accurately, and part geometry matters so much that each part will have its own unique scaling.
at 22:48 you have the right answer becuase the margin is so small, but the math to find the correction amount I believe should be 1 divided by ratio rather than 1 minus ratio. In this case the answer is the same.. Shinkage also relates to % of infill - so that would be a factor.
First time I've watched one of your videos. _WOW!_ My sample size is a bit small here but I still believe I can confidently say: You make excellent videos! You explained EVERYTHING you did and why you did it (and you knew how to explain it because you really do understand what you're doing rather than just being a talking head!). Now, for me, I understood what you were doing and why. My nine-year-old son, who wants to get into electronics? Not so much. You can bet you're about to get another couple of subscribers. Also, excellent production quality. I've seen a lot of people who really know what they're talking about that, unfortunately, either have very poor communication skills or just cannot seem to put together a video that makes any sense. Eventually those people just quit making videos because they don't get many subscribers. This is, honestly, a real and serious loss to people looking for usable information rather than entertainment.
I'm also wondering why you're not just printing with eSun's PLA+? eSun's (black, of course...) PLA+ was the first filament I bought. I really don't have any troubles with shrinking, warping, or anything else. (Disclaimer: Pretty much everything I'm printing, while it often needs to be dimensionally accurate, is usually so small that anything less than 10% error isn't going to make any difference anyway.) I suppose ABS _is_ a bit stronger but, is that really a consideration for this part? I suppose it could also be a matter of cost. ABS is, I know, generally less expensive that PLA. To be honest, though, given what I've heard about the charming fragrance you get when you're printing ABS, I'll happily pay extra until I can build an enclosure with a vent to the outside of my house. What kind of printer is that? Is it something you designed yourself?
I don't know if someone already pointed it out, but scaling up x% will not make your part come out at the desired size if its shrinking due to the material by x%. The right amount you would need to increase the print should be equals to (100/(1-x/100)-100) % which can be approximated to x% but it is not precisely the same. For example, if your part is shrinking by 0.5% then x = 0.5 and thus you would need to increase the model by (100/(1-0.5/100)-100)% = 0.50251256281%
Yes. That has been pointed out. In this case, the lack of precision in the original measurement swamps that error. But I believe you now hold the record for decimal places. :)
This was a great video to watch. Ive been having an issue of critical cylindrical features being undersized in a part. Ill definitely try your method out.
Thank you for sharing your solution! Very easy to understand explanation and solution. I've seen a few of your other videos and as always, you do an excellent job of presenting your topics in a clear, well organized fashion. Keep up the great work!
I've learned about the shrinkage issue purely by experimenting initially, but did some research afterwards. The shrinkage is real and is based on many things, including material, nozzle, heatbed temp, room temp, and so on. ABS, not sure about ABS+, is known to have as much as 7% shrinkage rate in some cases and PLA around 2% and nylon around 1.5%. I've changed my 3D printer once and the rate changed as well. Here is the deal. Print a ruler when you use your 3D printer for the first time or in a new environment and figure out the shrinkage rate, AND try not to change the room temperature and ventilation too much form that reference. You'll be alright.
I've seen numbers for ABS quoted as high as 8%, but I think someone lost a decimal point and others have quoted that source. I would have to see shrinkage like that to believe it.
@@Clough42 No, the 3D printing community isn't that stupid. The ABS the material’s high coefficient of thermal expansion can cause upto, meaning maximum of, 7-8%. Shrinkage rate of 1-3% is commonly reported by many users. It's also depending on whether it has a filler or stabilizer. If you need to see it to believe it, try printing it near open window in a cold windy night. You'll quickly see that decimal point number goes away very quickly.
Suggest doing a physical calibration of all the axis of the printer: mark current position, move 10cm, measure, repeat for all axis. Math and real-world often don't match up. Also, filament shrinkage isn't consistent in all directions. Is the height of the frame also correct now or is it a tad higher than expected?
^ ^ ^spot on this. A dial gauge clamped to the frame and a couple of gcode commands would validate the chassis, repeat for x, y and z Due to the layering the z will certainly be different - in my experience it has been significantly less than x and y
Physical calibration of the printer is a good idea, but even if it's perfect, the plastic will still shrink as it cools. I did measure the height of the part. From the base to the register for the PC board under test is modeled at 12mm. I measured it in three places and got values between 12.01mm and 12.03mm. That's plenty close for a 3D-print with .2mm layers.
I just saw this video Shinkage was my first thought. I do a Single Wall Calibration cub as well as an 2mm x 2mm full cal cube to get as close as I can to curate dimensions. You probably have to repeat this process for different types of material.
I would have liked to see all 4 holes checked at the same time, OR at least diagonally opposite holes. Keep up the great video work. I off to check to see if CURA provides those settings for my printer. THANKS
Zplizor not true material shrinkage happens isotropically I can’t think of a manufacturing process that would cause anisotropic shrinkage. Please educate me
@@HypeBeast764 I fully agree for molded plastic.. But due to the layeing 3d printning do achieve a semi anisotropic mode.. Do a short search for abs layer separation.. This is partly due to the stresses in x and y
Zplizor I can see where you are coming from and I used to think the same but unfortunate not true for small parts or parts printed in a heated chamber. You’re right, layer separation is due to stresses in the material and that’s due to a temperature gradient. On small parts, and parts made in a heated chamber the ambient temperature remains close to the bed plate temp. You can calculate shrinkage by using the linear thermal expansion equation and calculating delta T as the bed temp minus ambient room temp. To clarify I mean small parts as in short parts with respect to the Z axis, so parts that are not tall. You’re right however that on MOST printers that if you create a tall part that this won’t work, but that doesn’t matter because you can’t make tall parts on a printer that has a bed that is completely exposed to ambient room temperature. Ultimately gets around this with a kit to seal 5 out of the 6 walls surrounding the printer.
@@HypeBeast764 I agree, i have only printed a limited number of big abs parts, and here i didnt compensate for z, thereby i deducted that it wasnt needed due to the layer building nature
Zplizor yeah so I was determining the CET for Ultimaker ABS through test prints and measurement at work and found that it’s super low, almost so low it’s negligible. I think some 3D printing blends may be so low it’s almost not even worth factoring unless you’re printing something needing precision and takes up the whole build plate. For a 120mm part I was getting around 0.249% contraction at room temp. I know that 3D print blends try and reduce the CET as much as possible for 3D printing at the cost of material performance with the exception of Makerbots Real ABS that is designed for the method which has a heated build chamber. So depending on what material you’re using you may not even need to compensate as the impact could be negligible. Typical ABS has a CET that would contract the part from 0.596% to 0.793% so only contracting 0.249% is super low
Here is my experience with 3d printers which run on pulleys and belt, the numerical calculation is always not equal to the distance traveled by the component. Yes, parts do shrink but the best way to calibrate the sizing is to manually move the printer a set number of whole steps and measure the distance traveled on the printer. Make sure the belts are tensioned to your liking before this of course. After this calibration has been done to the steps/mm of the printer then you can calibrate shrinkage on a filament by filament basis.
This is correct. I did some measurements at one point in the past and decided it was negligible for my use case, but the printer's been running for 3 or 4 years now without any adjustments, so it would be worth checking again.
I agree. I think that this video is based upon an assumption that wasn’t correct and was not really proven by disproving all the other possible causes. This could be misleading to people thinking that shrinkage is the cause, when in fact it’s the cheap GT pulley wheels that are introducing an accumulating error.
Thanks for your experience and how you fixed your specific problem. I'm using Cura so I have to explore my options and I also have to verify if I do this whether or not already made .STLs haven't been scaled up for a material if I go this route. But I really like how this would alleviate some of the headaches of issues related to FDM printing for my use case.
Yes and no and yes. It began life as a frame kit from MakerFarm (12" i3v with the laser-cut wood frame). I built it up with eBay motors and electronics, a silicone industrial heating mat and more than a few parts I designed and printed to solve specific issues. The dual extruder is my design (Itty Bitty Double FLEX V2). Mostly at this point, I just use it. I don't think I've even taken a screw out of it or adjusted anything in about three years.
I think this depends on the temperature gradient in the part during the print. For tall parts without a heated chamber, I would expect a different average shrink factor, but I would also expect it to vary with height off the bed and also with part geometry that might block airflow.
Very interesting and informative video. I don't 3D print much so it's trial and error for me but the next time I'll measure and do the math to see if it'll help me. I don't know if Cura has that save option but I'll look. I generally measure on the fly while printing and stop it if too small or too large and re-size. Hell, I'm old, retired and still learning!!! LOL! Thanks for the informational video, makes me think more.
Mr James, you are truly a genius. I love the fact that you not only show/explain how to do things "right"; but you also explain how NOT to do something. Both of these factors are important in the execution of any process. You're also very professional and your video-editing is like few on RUclips. Thank you for sharing your videos. May Jesus continue to bless you.
I also print engineering parts for my designs. After a few dummy runs I ended up using 100.5% scaling factor for PETG. likewise, I use Simplify3D but wasn't aware of the option to auto scale. Thanks for the tip. Some of my projects have moving parts and gears ...etc. so now I'm thinking of getting into SLA for accuracy, detail and maybe strength? Love your channel.
There is a parameter called horizontal expansion or similar in the slicers that you may want to check. It should do exactly this and you can configure how much you want for each material you use so you don't have to remember to scale up each piece for each material differently. It doesn't expand z axis though. Good video and very well explained.
WoW. I really enjoyed this video, very well layed out & explained in a logical way. I am just a day away from using my first roll of ABS & now I know how to deal with part inaccuracies. Great timing for me thank you very much, I've subscribed & am eager to see more of what you do. Cheers Di
Thank you very much, this information and explanation will solve and make a big difference to those that are trying to get into 3D printing and can't understand why their parts don't finish dimensionally accurate. The information you provided, how you arrived to your problem solving methods and ultimately the end result were great. I just wish i knew more about Excel to do a simple number processing file as you did for averaging numbers(measurements). This will be something i research now as it will help me a lot and speed up my post part analyzing process.
Some time ago I made flat square (0.2mm tall and 0.4mm thick) and measured for machine travel accuracy. I also turned it 45 degrees and measured again to test if the machine was properly squared. Didn't bother making a model with both included, like a star of David if you will. And wondered about Z travel, but that might be better tested by counting full turns of the stepper motor and measuring height change, as that would have more to do with the demential accuracy of the lead screw.
If the issue was shrinkage as the part cools, wouldn’t you witness this as the part cools on the bed? Could you attach a dial indicator to your printer and move the gantry and check the movement? It feels as though the diameter of the GT pulley wheels might be in error. After all, any error will be multiplied up by the number of rotations. Hence why, although we can in theory calculate the steps/mm, it’s best to perform a physical measurement to do the final correction.
It is possible to observe it. If you're sitting next to the printer as it cools, you can hear it cracking and popping as it shrinks faster than the glass and pops off the bed. Small errors in GT2 timing pulleys do not accumulate over multiple rotations because the teeth keep the belt synchronized.
I ran into the same thing making a part for my Dad to fix a clock. We needed to drill a pendulum because the rating nut stem broke off. The square rod was 4mm square and his jewelers lathe dead center end was 7.61mm and round. So, being the "smart nerd geek" I printed a 7.61mm cylinder with a 4.1mm square hole in it. It didn't fit! The cylinder turned out to measure 7.43mm and the square cutout...4mm (tight, more like 3.99mm). So back to SolidWorks and this time I would not be robbed! The cylinder was not so critical, so we left that alone, but the square hole, we made 4.23mm and I made relief cutouts (very small circles, .02mm) in each corner. We were VICTORIOUS! the clock lives and my Dad saw that a 3D printer was not just to print "Groot" and other frivolous toys. It had real world applications and in its own right, is a useful tool. But make no mistake, shrinkage is real. If you have parts that must interact or pass through or by, measure and use the shrinkage calculations to determine proper fit before you print everything for a project. Especially for a new project!
This is an awesome video! Material shrinkage is something I've never thought about or even considered when modelling. But I will be factoring it in when printing dimensionally accurate parts from now on. Great job!
Great video. If only i could whip through excell as fast as you. Thanks for sharing this because I have noticed just recently that parts which require fitment need some research regarding shrinkage as well as other factors.
When you export from Fusion 360 the mesh quality will affect the dimensions. Happened to me when I right-click and "save as mesh" and send to the 3d printer.
I print the part 4 or 5 layers high and stop print. Check the size and adjust for shrinkage. Saves on material and time on a full print. I also use this method to make templates for drilling holes.
I'm generally going to print a part several times during the prototyping process, so I generally expect that I'm going to scrap a few for reasons other than fit. It's just so easy to print overnight or while I'm at work and then make adjustments and print again.
cool video! One small trick, not sure if it is already mentioned here: measure the pin size with calipers, now *zero the caliper*, then measure the outside distance between pins - it'll give you the exact distance between pins.
If the pins are the SAME size His were not (but not greatly different so, in THIS case, can be ignored).
Great idea, and now I feel stupid for never thinking of that.
Good reminder that it's all fun and games when printing big-busted winged figurines - until you need to print something practical.
I managed to print a 50 cm replacement oven door handle, and I had kept the old aluminium face. The face had a lip (perpendicular to the face) and a rounded bevel. I designed the handle with zero clearance for the lip, a matching radius, a groove of the exact width and depth.. It was my first 3d print on my first 3d printer (say .. project larger than a few cm), and it worked as expected. The aluminium face fits nicely in the handle...
I used PLA, a 60C heated bed all the time (9 hours), a nice and big raft, and the printer is a Creality CR10 Max, 0.4mm nozzle, 70mm/s. My only complaint is that there is a 0.1 mm deflection over the 50cm of the handle, other than that, I'm happy with the result.
exactly, btw. I almost always print somethinf practical , no time for wasting my filament and time for useless things..
.stl of big-busted winged chicks or it didn't happen.....
Naaaah, just kidding, I wouldn't want to treat women like .obj's.
@@redwhiteandbluebonnets8180 😂
@@redwhiteandbluebonnets8180 You mean ...treat women like stl's 🙂
The way you troubleshot this and your thought process driving your actions were outstanding. Well done
Just so you guys know if you are using PLA and your parts are slightly to big (or your holes are slightly too small) your issue may be solved by increasing your horizontal expansion offset. Basically the PLA is expanding just a little bit due to the heat of melting it, so your parts will be just a little to big. The horizontal expansion offset can help fix this. You will need to do multiple tests seeing what value works best for you.
good to know !
Thank you
In SuperSlicer would that be XY Compensation?
@@fred98321 I believe so
@@Kz1nk Yes, it was. I played with it and it solved a long standing problem. My XY movement is calibrated based on distance moved but parts were never the exact set sizes. After using XY Compensation they come out very close (0.02 to 0.04mm) to the defined size. Thanks again.
@@fred98321 Awesome, glad it worked!
For precise features, we usually CAD those features in a very thin, quick, proto print to get them accurate. Then the full size part. This saves lots of iterative printing time and waste material. Also for threads, snap fits, flex fits, and anything that fits something from "the real world" or even another printer.
I don’t even try to get small holes or threads correct, I’ll undersize them then drill and or tap as needed. Super easy Bc it’s plastic
@@henry3397 You still need the centers correct, though.
Holy cow. I'm very new to 3d printing, only actually printing about a dozen things. They were always too small, and since all of this is new to me, and there is a plethera of new terminology, I've been scouring the interwebs trying to figure out why. I thought my printer was either broke, or there was some calibration sequence I needed to do. I had basically given up, frustrated that I had to manually model everything larger to compensate, since I had no idea what was wrong.
And then youtube dropped this in my lap. Thanks so much for taking the time to make this. No overly complicated terminology and a very simple solution. You saved my sanity!
I hope your tester came out well!
Great video. Just pulled my old Tarantulas printer out printed an insulated spacer had almost exact errors you had. Your video confirmed my method I was about to do this morning. I am electronic designer by trade, worked with lots good machinist over the years each taught me real world solutions just like this video series. Big thank you.
I work in a 3d printing lab and we have had this same problem. I haven't thought of this solution so thank you this will save a lot of time and money.
How would the pros solve this problem?
I just wish all RUclips videos were as clear and concise as this. Great Job....!
Love the “to my calibrated eye” ! I use that all the time. Nice clear and thorough explication of the shrinkage problem and how to fix it. I just bought a FDM printer and learning how to use it and that is an issue I have run up against. Thanks for the great video!
It would be great if you could do a similar video, showing the full process of calibrating the printer for accurate dimensions and setup of Simplify 3D. Your way of explaining things is really good.
I think the point of this video was to get a really accurate part with out touching your "already calibrated" printer. Because let's face it, all part behave differently and calibrating the printer for each part is quite annoying/time consuming. I am sure you found that out yourself anyways.
Very interesting. I suppose the shrinkage changes based on the thickness and shape . . . . . if it were directly proportional, no matter what, printing a set of 12" "rulers with very fine scale marked, then compare to actual ruler and maybe that would tell you whether the shrinkage happens across the scale, or jsut in certain parts?. Love your videos, and the Fusion 360 has been far more useful than what pertain to be F360 tutorials. You make it far clearer than those other guys! Thanks!
As a retired guy it was an excitement to look a t this video. I think I’ll set aside my resin printer just to try your ticks. Thanks. JP.
in the beginning i thought, that you didn't calibrate your axis correct, but your solution and description are GREAT...
a new aspect to improve my parts. thx ;) hope that the software desire not too much manual changes in settings when changing filament OR temp!
automatic part-enlargement should be mandatory for filament-settings ... NOT after importing, but BEFORE PRINTING!
Thank you for sharing your experience with us and I really enjoyed the video presentation. It showed me how one should go about dealing with shrinkage.
Things that I noticed and hope you will continue to do include:
You don't assume too much of the experience or knowledge of your audience which I think is great.
You disclosed brand names of what you used (filament, 3D program, 3D slicer, spreadsheet, etc.) which I liked. It gives me ideas on how I can use them more effectively or in my environment. Your spreadsheet usage was particular interesting to me.
You scripting of your video was well done in that you presented what you wanted to do, demonstrated the problem (with lots of visual close up shots) on what happened, how you identified the problem, the possible solutions and the final solution that you settled on.
I thought that a visual inspection of the 3D object would have suggested that the problem was not in the hardware (i.e. 3D printer) but somewhere else since the printed object looked pretty good. But I do commend you for doing your 'due diligence' to make sure that you didn't miss anything as part of your problem analyze segment. As a side note, I thought that if I were looking for the actual shrinkage value due to the equipment & material, I would print the largest diameter rectangle that my printer to produce and measure the resultant print. The deviation between designed & actual dimension would be the most accurate.
But back to the video.
The pacing was sometimes fast, especially when not familiar with the application or situation but I was able to follow it. The video presentation was professionally done, with great video framing & sound reproduction. Thank you especially for taking the time to do a great presentation.
Finally, I do want you to know that I appreciate the time & effort that you put in producing the video and encourage you to continue to do so.
Take care and stay safe,
Pat Young
Nice example. Thanks for taking the time to show that. Using Siemens NX, I like to add manufacturing specific features like this at the end of the model history, and place these features in a named feature group. That way I model the part as it should be, and then have a group of features for 3D printing (or other manufacturing process) that can be suppressed or unsuppressed as a group. For example, I might enlarge holes slightly based on inaccuracy of the 3D print. Scaling the final part for shrinkage would be a feature in the feature group.
Husband Richard saw you on wife's phone and I subscribed cuse I love to build and design and create .you video was helpful to me with your concise explaining I could understand perfectly. Now I will remember shrinkage.
Every now and than I will reach out to you with 3d print solving for help. Very well done 👏
Great engineering level video thank you. “I’m using black because BLACK” 🤣
Good work
One of the best videos on this problem I’ve seen. Thanks man!
I am a photographer. I still use the old 4X5 field cameras. Last year I bought an MPP MK VII technical field camera for landscape photography. It came with one lens board of Copal 1 size. This camera has not been produced since the early 70s so, instead of paying silly prices for battered old lensboards off the Bay, I decided to 3D print them using a CF infused PLA. I ran exactly into the same problem as you just did. Both trial size No 0 and No1 boards came out undersized. I had to adjust the printing sizes in Cura by quite a bit , around 1% mark If my memory serves me right, to get the lens flange to fit the holes and the retaining nut fit in. I am not quite 100% sure if the quoted filament sizes are accurate or not either.
You can change to a Z up orientation in Fusion 360 by clicking on your name in the upper right and selecting "preferences". In the general tab look for "default modeling orientation" and change it from "Y up" to "Z up"
YES, finally someone who is using 3d printing for engineering purposes. Altho I'm looking for DLP tips, this came very handy for those mucked up designs :)
What DLP tips do you need?
Excellent tip. No more drilling, dremel’ing, filing, etc. post printing. Thank you very much.
What a tremendously presented study of shrinkage and the solutions thereof.
Wow this explains so much. I've ALWAYS had an issue with things being printed a little undersized and I've been 3D printing for 7 years now. I figured it was just my crappy old printer. I've been setting my prints to 101% or 102% for a long time, but great to know the reason now.
To other viewers: Before you assume that it's your filament material that's shrinking, print some lines that are a known distance apart *but not connected to each other* and check the dimensional accuracy between them. That way you'll factor out the shrinkage and see the true dimensional accuracy of your printer while the parts (the lines) are still stuck to the print bed.
This can be very hard to do accurately, since the differences we care about are small, and layers near the bed are often distorted. I would prefer to measure the actual movement of the printer axes with a caliper or dial indicator.
Could be underextrusion because of constant in extruder or nozzle diameter, also, bed testing isn't the best idea. It's that first layer that is either squished to ensure great adhesion or with offset for easier removal which add a bias factor in consideration.
Cryocide material shrinkage isn’t an assumption. It’s a well studied physical phenomena and he also just empirically verified it.
@@Clough42 The way I tend to do this is by printing an L-shape with equal length legs and square holes at the ends and intersection of the legs. Say the L-shape has 120mm legs, each 20mm wide. There are three 10mm square holes, each with their centre lines 100mm apart. To get the correct axis scale, I measure the internal size of one such hole and zero my calipers on that dimension. Subsequent inside measurement of the holes' furthest sides (in this case 110mm) will show the pitch of the holes' centres. This way all factors involving extrusion width are eliminated, leaving just the actual printed dimension*. The hole sizes can also be averaged, of course, but I've found this to give me rather excellent accuracy in my prints, yielding running fits or press fits wherever I see (wait for it) fit.
I take it you choose the print scaling over a permanent firmware scaling of your axes as a material-specific compensation?
(* source: moi, being a B.Eng. in mechanical precision engineering 😁)
So that explains that😂 learning as I go along, but was disappointed with why my perfectly designed part was too tight in the real world. And now I know! Thanks for a great lesson!
Nice and succinct explanation. I've run into a similar issue and hadn't considered material shrinkage despite ruling out the same mechanical factors. My error is of the same magnitude hence my new suspicion of material shrinkage. Thanks 👍
You can go to preferences in Fusion and change so Z is up :)
Was just going to post this same comment
Yes you can change the preference "Default Model Orientation" to "Z up"
Maybe "Y up" works better for the CNC mill
Yeah, @ThisOldTony just did a video on how bought a new milling machine, I mean fräsemachine, had weird axis labels. They appear to match default fusion 360. I’ve always been taught if you’re facing the machine, x is starboard to port, y is aft to fore, and z is below to above. Making the back, bottom, left, 0,0,0.
Thanks! That's probably the best long-term solution.
@@areospike1600 I believe his model was based on a horizontal originally so the spindle axis (Z) would be what we'd consider Y. Why they kept the scheme is confusing though.
My ender 3 has sat for 5 months.... been moved... cats walk across it...i finally started printing again and printed 10mm and 20mm test cube, without leveling my bed, just cleaning the glass, and my parts came out .02mm off. Not too damn bad. Printed a print in place box with attached hinged lid... and i didn't even have BREAK free the hinge, it rotated right away. Love it.
I got around a lot of these issues by building all my models in metric. I've not had any issues with size or accuracy since. I live in Ohio, but having worked for a few European based companies in my life, I've had to learn metric. Best thing ever, and never thought it would come in handy. But I use this at work and at home for the printers and designing in metric has helped SO much.
Give it a shot!!
Changing the measuring unit does nothing to address shrinkage between the software model and the printed part. As long as your design maintains a consistent system of units you're fine no matter what system you use.
@@mystixa I mean, given I've had the issue and made the correction and have physically held the correct result in my hand.... Sure.... I'll go with your suggestion..... :/
@@That_guy_Pip One has nothing to do with the other. I wasn't suggesting anything other than maintaining a consistent set of units when measuring. It doesn't matter if you call them xblocks or furlongs as long as your measurements remain self consistent.
awesome! I found this as well with fitting a circuit board. You are the only one on the internet with the right fix. I spent a lot of time going down the wrong rabbit holes lol. subscribed!
To get the maximum precision, you should print a test piece at the largest size possible, that way, the shrinkage will be amplified making it easier to measure.
pro tip: don't print it bigger than your callipers.
instablaster...
@@gonun69 Yeah I had to learn that the "hard" way.
I just watched the same type of video on ItsMeaDMaDe and both were informative and I enjoyed watching them both. I really like how in-depth you get in all of your videos. Thanks for sharing
Great video But if you design for assembly shrink would not be a concern for hole pitch.
Great info video, thank you. The only thing I can think of since the slicer allows one setting at a time, is to just print a chart with the shrink rate of each filament material used. When imported into slicer, double click and change parameters accordingly before printing.
It really depends on what you're doing. In my case, most of what I do that requires precise dimensions is in ABS, so one setting gets me close enough. If I routinely required precision in lots of different materials, it would be necessary to do exactly what you describe.
@@Clough42 yep, that is all I was referring to, so I hope you didn't take it like I wanted to help you out. You're way ahead of me, I only commented for viewers who might (for whatever reason) used a variety of materials. For me, probably PLA.
@@FrugalFlyRodder yeah, no problem. I learn stuff from comments all the time.
This may be late, but wouldn't you scale by the reciprocal of the part scale (e.g., to account for a shrinkage of 25% that would result in a part at 75%, you would scale by 1/0.75=1.333...)
Ah i put this 100.5 to correct my issue, now i have started to research this and i was right all along, thanks for making me sure.
Been 3d printing now for 3 years and still have been doing the scaling manually on simplify3d. Thankw for making my 3d printing life much simpler. I do a lot of mechanical parts so this helps a lot.
What happens when you use a different filament or printer?
Are you going to keep track of what you scaled each and every part with?
So your method is actually the preferred method.
Talk about building "fact on fact"; YOU James would make an unbelievable detective. Oh yes you would be indeed. In my 87 yrs on this earth, it would be difficult to find any one that is as brilliant as you are. You are truly a "gifted" man (Praise Jesus) dear sir! We can't wait for each new video you produce. Keep it up.
Thanks for the compliment(s).
@@QueueTeePies Yes I am that age. And blessed beyond my ability to describe. And you know who I give ALL the credit too. Praise His Holy name.
Thank You! Mind Blown! Once my 3D Skill Level is ready for action, I'm gonna make some super custom sewing machine presser foot attachments (to help glide over stubborn fabrics). Schooling us that the ABS 3D Printer filamint will shrink a bit after it's cooled greatly reduces my shock expectancy of my first printed piece.
I use Prusa Slicer but think this may be applicable to it as well and may explain some of the fit problems I have seen. Also have found that the way I set up the walls makes a difference. Printing the outside of wall first or last to compensate for extrusion squish.
Thank you so much. O was looking around to cope with that problem with abs for a very long tiime
That's cool. I don't use ABS much, mainly because of the warping issues. As such, I wasn't considering, and should have!, that your part shrunk. I thought it was a belt, or estep issue. My thought would be to confirm this using some digital calipers as DRO's on the x and y carriage. My first printer ever was semi-scratch build off of a Shapeoko 2. I was able to use digital calipers to show pretty accurately, and with some precision, X and Y movements, to really tune my esteps. Cool video, as usual! Thank you James!
The pitch of the GT2 belt is actually only valid for a particular specified belt tension. If the tension is wrong, the pitch is wrong, because it does stretch by quite a bit! Well then again that's my experience and i use Chinese parts and not Gates belt. But its easy to check, you tape your calipers down under the nozzle when it's close to the bed, jog the head a bit via controls, zero the caliper, and then have the print head walk a known distance and compare. It's probably pretty close, not enough to make up that difference.
The claimed 0.8% shrinkage for standard ABS is significantly less than what i've seen myself, i expect closer to 1.2% shrinkage. I think they have a measurement method which is very kind to shrinkage number. But any figure is a rough guideline since shrinkage is non-uniform depending on shape.
From the moment I read the claim of 0.4% shrinkage, I assumed my results would be a little worse. They're definitely not going to publish the worst-case scenario in the marketing literature.
@@Clough42 yeah I wonder if the Z axis has the same shrinkage
@@nirodper You might be surprised, often times when the print shrinks, the XY shrink but Z expands a little - just a little! Something about molecule orientation, you can imagine them as springs, you lay them out predominantly lengthwise along your extrusion direction, and when you release and cool down the print, they shrink down; but the material still has to go somewhere. The print shrinkage is not merely or predominantly thermal shrinkage, as you can see, say PETG has no print shrinkage whatsoever.
Very nice. I know that Kira can let you specify the dollar amount of a roll of filament and then perform the calculations to tell you how much your part costs in filament. But I haven't looked at any additional filament just settings.
Really enjoyed your video. It's about time that silly algorithm got around to presenting it to me. I was searching for horizontal expansion on RUclips. What I really want to do is tune the machine. Thanks so much.
Another outstanding video that explains why I had to keep scaling my parts to fit precisely! By trial and error, the factor for my ABS was 1.1%!
Now this is what I love about this channel, you just know that when James does something...he does it right!
Yet another great video James, keep it up mate! 👍👍👍
You can edit your process settings and set a profile for each type of material you want to use. Then on each profile under the Other tab set the Horizontal Size Compensation appropriately for that material
This setting may not do what you think it does. Check the follow-up video.
I noticed that your 3D printer X axis is using a belt, use same config as Z axis material but also a solid coupler not the one looking like spring. This should fix it.
Your videos are awesome, thanks for sharing.
In the metal casting world, a common tool used is a shrink rule, each graduated for a specific material with a known percentage of dimensional increase, so that a casting model made using the correct rule for that material will result in a cast part of that material which is the desired final size.
So that means “what you want” finished, is, design scaled - plus oversize for 3D printing - plus - oversize for metal shrinking (using the 3D printed part for loss casting) - and - oversized again for subtractive machining. Not only does SIZE matter, but at X4. And at different values for each type process. (Not even getting into the whole SAE/Decimal/Metric conversation thing...OR rounding up/down) I love it.
The same thing is done in dental lab work. The wax shrinks a known amount. The metal does too. The investment expands a known amount to compensate for the combined shrinkage
Don't have a 3D printer yet, but this was educational as someday one will be making its way home with me and it's good to have a heads up regarding print issues that one can experience.
filament temp also matters. I use mostly PLA, and if I run it at 190 vs. 200 for the one I use for instance, it prints more accurately, and part geometry matters so much that each part will have its own unique scaling.
there's a feature in Cura where you can compensate for expansion /contraction in the setup .
Thanks for the great advice, I never considered the shrinkage of the material being used. Makes a lot of sense!
it is awesome to see some real engineetring work on the topic.. thanks bro...
at 22:48 you have the right answer becuase the margin is so small, but the math to find the correction amount I believe should be 1 divided by ratio rather than 1 minus ratio. In this case the answer is the same.. Shinkage also relates to % of infill - so that would be a factor.
First time I've watched one of your videos.
_WOW!_
My sample size is a bit small here but I still believe I can confidently say: You make excellent videos!
You explained EVERYTHING you did and why you did it (and you knew how to explain it because you really do understand what you're doing rather than just being a talking head!). Now, for me, I understood what you were doing and why. My nine-year-old son, who wants to get into electronics? Not so much. You can bet you're about to get another couple of subscribers.
Also, excellent production quality. I've seen a lot of people who really know what they're talking about that, unfortunately, either have very poor communication skills or just cannot seem to put together a video that makes any sense. Eventually those people just quit making videos because they don't get many subscribers. This is, honestly, a real and serious loss to people looking for usable information rather than entertainment.
I'm also wondering why you're not just printing with eSun's PLA+?
eSun's (black, of course...) PLA+ was the first filament I bought. I really don't have any troubles with shrinking, warping, or anything else. (Disclaimer: Pretty much everything I'm printing, while it often needs to be dimensionally accurate, is usually so small that anything less than 10% error isn't going to make any difference anyway.)
I suppose ABS _is_ a bit stronger but, is that really a consideration for this part?
I suppose it could also be a matter of cost. ABS is, I know, generally less expensive that PLA. To be honest, though, given what I've heard about the charming fragrance you get when you're printing ABS, I'll happily pay extra until I can build an enclosure with a vent to the outside of my house.
What kind of printer is that? Is it something you designed yourself?
I don't know if someone already pointed it out, but scaling up x% will not make your part come out at the desired size if its shrinking due to the material by x%. The right amount you would need to increase the print should be equals to (100/(1-x/100)-100) % which can be approximated to x% but it is not precisely the same. For example, if your part is shrinking by 0.5% then x = 0.5 and thus you would need to increase the model by (100/(1-0.5/100)-100)% = 0.50251256281%
Yes. That has been pointed out. In this case, the lack of precision in the original measurement swamps that error. But I believe you now hold the record for decimal places. :)
This was a great video to watch. Ive been having an issue of critical cylindrical features being undersized in a part. Ill definitely try your method out.
Thank you for sharing your solution! Very easy to understand explanation and solution. I've seen a few of your other videos and as always, you do an excellent job of presenting your topics in a clear, well organized fashion. Keep up the great work!
I've learned about the shrinkage issue purely by experimenting initially, but did some research afterwards.
The shrinkage is real and is based on many things, including material, nozzle, heatbed temp, room temp, and so on.
ABS, not sure about ABS+, is known to have as much as 7% shrinkage rate in some cases and PLA around 2% and nylon around 1.5%.
I've changed my 3D printer once and the rate changed as well.
Here is the deal. Print a ruler when you use your 3D printer for the first time or in a new environment and figure out the shrinkage rate, AND try not to change the room temperature and ventilation too much form that reference. You'll be alright.
I've seen numbers for ABS quoted as high as 8%, but I think someone lost a decimal point and others have quoted that source. I would have to see shrinkage like that to believe it.
@@Clough42 No, the 3D printing community isn't that stupid. The ABS the material’s high coefficient of thermal expansion can cause upto, meaning maximum of, 7-8%. Shrinkage rate of 1-3% is commonly reported by many users. It's also depending on whether it has a filler or stabilizer.
If you need to see it to believe it, try printing it near open window in a cold windy night. You'll quickly see that decimal point number goes away very quickly.
Great video, thank you for taking the time to go through all the details 🙏🏾
Suggest doing a physical calibration of all the axis of the printer: mark current position, move 10cm, measure, repeat for all axis. Math and real-world often don't match up.
Also, filament shrinkage isn't consistent in all directions. Is the height of the frame also correct now or is it a tad higher than expected?
^ ^ ^spot on this.
A dial gauge clamped to the frame and a couple of gcode commands would validate the chassis, repeat for x, y and z
Due to the layering the z will certainly be different - in my experience it has been significantly less than x and y
Physical calibration of the printer is a good idea, but even if it's perfect, the plastic will still shrink as it cools. I did measure the height of the part. From the base to the register for the PC board under test is modeled at 12mm. I measured it in three places and got values between 12.01mm and 12.03mm. That's plenty close for a 3D-print with .2mm layers.
I just saw this video Shinkage was my first thought. I do a Single Wall Calibration cub as well as an 2mm x 2mm full cal cube to get as close as I can to curate dimensions. You probably have to repeat this process for different types of material.
I would have liked to see all 4 holes checked at the same time, OR at least diagonally opposite holes.
Keep up the great video work.
I off to check to see if CURA provides those settings for my printer. THANKS
Great video! So much knowledge and perfectly explained the issues I was having with ASA. Thank you
This is a fantastic video. Clear explanation of problem with simple workaround. Subscribed!
You normally only compensate in XY, as Z isnt affected in the same way, due to layers building upwards
Zplizor not true material shrinkage happens isotropically I can’t think of a manufacturing process that would cause anisotropic shrinkage. Please educate me
@@HypeBeast764 I fully agree for molded plastic.. But due to the layeing 3d printning do achieve a semi anisotropic mode.. Do a short search for abs layer separation.. This is partly due to the stresses in x and y
Zplizor I can see where you are coming from and I used to think the same but unfortunate not true for small parts or parts printed in a heated chamber. You’re right, layer separation is due to stresses in the material and that’s due to a temperature gradient. On small parts, and parts made in a heated chamber the ambient temperature remains close to the bed plate temp. You can calculate shrinkage by using the linear thermal expansion equation and calculating delta T as the bed temp minus ambient room temp. To clarify I mean small parts as in short parts with respect to the Z axis, so parts that are not tall. You’re right however that on MOST printers that if you create a tall part that this won’t work, but that doesn’t matter because you can’t make tall parts on a printer that has a bed that is completely exposed to ambient room temperature. Ultimately gets around this with a kit to seal 5 out of the 6 walls surrounding the printer.
@@HypeBeast764 I agree, i have only printed a limited number of big abs parts, and here i didnt compensate for z, thereby i deducted that it wasnt needed due to the layer building nature
Zplizor yeah so I was determining the CET for Ultimaker ABS through test prints and measurement at work and found that it’s super low, almost so low it’s negligible. I think some 3D printing blends may be so low it’s almost not even worth factoring unless you’re printing something needing precision and takes up the whole build plate. For a 120mm part I was getting around 0.249% contraction at room temp. I know that 3D print blends try and reduce the CET as much as possible for 3D printing at the cost of material performance with the exception of Makerbots Real ABS that is designed for the method which has a heated build chamber. So depending on what material you’re using you may not even need to compensate as the impact could be negligible.
Typical ABS has a CET that would contract the part from 0.596% to 0.793% so only contracting 0.249% is super low
Here is my experience with 3d printers which run on pulleys and belt, the numerical calculation is always not equal to the distance traveled by the component. Yes, parts do shrink but the best way to calibrate the sizing is to manually move the printer a set number of whole steps and measure the distance traveled on the printer. Make sure the belts are tensioned to your liking before this of course. After this calibration has been done to the steps/mm of the printer then you can calibrate shrinkage on a filament by filament basis.
This is correct. I did some measurements at one point in the past and decided it was negligible for my use case, but the printer's been running for 3 or 4 years now without any adjustments, so it would be worth checking again.
I agree. I think that this video is based upon an assumption that wasn’t correct and was not really proven by disproving all the other possible causes. This could be misleading to people thinking that shrinkage is the cause, when in fact it’s the cheap GT pulley wheels that are introducing an accumulating error.
It was clear for me from beginning. But this video us ideal practical explanation.
Thanks for your experience and how you fixed your specific problem. I'm using Cura so I have to explore my options and I also have to verify if I do this whether or not already made .STLs haven't been scaled up for a material if I go this route. But I really like how this would alleviate some of the headaches of issues related to FDM printing for my use case.
did you design and build your 3d printer? great video ...yeah shrinkage is not fun...and it varies with diff brands of abs/pla etc...thanx for sharing
Yes and no and yes. It began life as a frame kit from MakerFarm (12" i3v with the laser-cut wood frame). I built it up with eBay motors and electronics, a silicone industrial heating mat and more than a few parts I designed and printed to solve specific issues. The dual extruder is my design (Itty Bitty Double FLEX V2). Mostly at this point, I just use it. I don't think I've even taken a screw out of it or adjusted anything in about three years.
@@Clough42 extrusion is the only way to go
Oh man, that is gonna save me so many test prints to calibrate and scale up whatever parts I need to be dimensionally accurate.
Generally, you shouldn't have to scale the z-axis as much for a FDM part as the scale for the X- and Y-axis.
I think this depends on the temperature gradient in the part during the print. For tall parts without a heated chamber, I would expect a different average shrink factor, but I would also expect it to vary with height off the bed and also with part geometry that might block airflow.
Yeah... Measuring x and y and then applying that to Z does seem like a drastic change in in carefulness.
Very interesting and informative video. I don't 3D print much so it's trial and error for me but the next time I'll measure and do the math to see if it'll help me. I don't know if Cura has that save option but I'll look. I generally measure on the fly while printing and stop it if too small or too large and re-size. Hell, I'm old, retired and still learning!!! LOL! Thanks for the informational video, makes me think more.
Mr James, you are truly a genius. I love the fact that you not only show/explain how to do things "right"; but you also explain how NOT to do something. Both of these factors are important in the execution of any process. You're also very professional and your video-editing is like few on RUclips.
Thank you for sharing your videos. May Jesus continue to bless you.
I also print engineering parts for my designs. After a few dummy runs I ended up using 100.5% scaling factor for PETG.
likewise, I use Simplify3D but wasn't aware of the option to auto scale. Thanks for the tip.
Some of my projects have moving parts and gears ...etc. so now I'm thinking of getting into SLA for accuracy, detail and maybe strength?
Love your channel.
There is a parameter called horizontal expansion or similar in the slicers that you may want to check. It should do exactly this and you can configure how much you want for each material you use so you don't have to remember to scale up each piece for each material differently. It doesn't expand z axis though.
Good video and very well explained.
Jes. But dit works not for the shrink. Only if you print parts that must fit together type holes
I think it’s amazing what you can do on the 3D printer! I am proud of you for finding a problem and fixing it! Good stuff James!
Thanks!
Thanks! I didn’t notice the Shrinkage percentage in the material spec! I just edited my drawing to compensate.😅
Outstanding! You are an amazing engineer! Great video, well explained.
WoW. I really enjoyed this video, very well layed out & explained in a logical way.
I am just a day away from using my first roll of ABS & now I know how to deal with part inaccuracies. Great timing for me thank you very much, I've subscribed & am eager to see more of what you do. Cheers Di
Awesome. Thanks!
Brilliant as always, James!
Another excellent video.
Dimension error... could be this, could be that. I feel better about Clough42 guesses than most people's facts.
Thank you very much, this information and explanation will solve and make a big difference to those that are trying to get into 3D printing and can't understand why their parts don't finish dimensionally accurate. The information you provided, how you arrived to your problem solving methods and ultimately the end result were great. I just wish i knew more about Excel to do a simple number processing file as you did for averaging numbers(measurements). This will be something i research now as it will help me a lot and speed up my post part analyzing process.
Nice work James 👍. Sigh, now I have to keep a crib sheet for filaments by brand/type and whack some small frames together and measure.
look into horizontal expansion settings in the slicer for more accurate prints
Some time ago I made flat square (0.2mm tall and 0.4mm thick) and measured for machine travel accuracy. I also turned it 45 degrees and measured again to test if the machine was properly squared. Didn't bother making a model with both included, like a star of David if you will. And wondered about Z travel, but that might be better tested by counting full turns of the stepper motor and measuring height change, as that would have more to do with the demential accuracy of the lead screw.
If the issue was shrinkage as the part cools, wouldn’t you witness this as the part cools on the bed?
Could you attach a dial indicator to your printer and move the gantry and check the movement? It feels as though the diameter of the GT pulley wheels might be in error. After all, any error will be multiplied up by the number of rotations. Hence why, although we can in theory calculate the steps/mm, it’s best to perform a physical measurement to do the final correction.
It is possible to observe it. If you're sitting next to the printer as it cools, you can hear it cracking and popping as it shrinks faster than the glass and pops off the bed. Small errors in GT2 timing pulleys do not accumulate over multiple rotations because the teeth keep the belt synchronized.
I ran into the same thing making a part for my Dad to fix a clock. We needed to drill a pendulum because the rating nut stem broke off. The square rod was 4mm square and his jewelers lathe dead center end was 7.61mm and round. So, being the "smart nerd geek" I printed a 7.61mm cylinder with a 4.1mm square hole in it. It didn't fit! The cylinder turned out to measure 7.43mm and the square cutout...4mm (tight, more like 3.99mm). So back to SolidWorks and this time I would not be robbed! The cylinder was not so critical, so we left that alone, but the square hole, we made 4.23mm and I made relief cutouts (very small circles, .02mm) in each corner. We were VICTORIOUS! the clock lives and my Dad saw that a 3D printer was not just to print "Groot" and other frivolous toys. It had real world applications and in its own right, is a useful tool.
But make no mistake, shrinkage is real. If you have parts that must interact or pass through or by, measure and use the shrinkage calculations to determine proper fit before you print everything for a project. Especially for a new project!
I learn something useful every time I watch one of your videos. Keep it up!
This is an awesome video! Material shrinkage is something I've never thought about or even considered when modelling. But I will be factoring it in when printing dimensionally accurate parts from now on. Great job!
Once Again ! Great solutions, for real world problems !!! Love this channel !!!
Great video. If only i could whip through excell as fast as you. Thanks for sharing this because I have noticed just recently that parts which require fitment need some research regarding shrinkage as well as other factors.
Glad it was helpful!
When you export from Fusion 360 the mesh quality will affect the dimensions. Happened to me when I right-click and "save as mesh" and send to the 3d printer.
I print the part 4 or 5 layers high and stop print.
Check the size and adjust for shrinkage.
Saves on material and time on a full print.
I also use this method to make templates for drilling holes.
I'm generally going to print a part several times during the prototyping process, so I generally expect that I'm going to scrap a few for reasons other than fit. It's just so easy to print overnight or while I'm at work and then make adjustments and print again.
You could change your steps in the start G Code of each printing preset. So it would change when using the presst for another filament.
Thank you. My projects have been coming out a little undersized. Now I know what to do.
Great video!! Thank you for the detailed explanation on resolving the issue