Couple notes on the results: - I'm currently not tracking how quickly filament is being pulled through the sensors. While this won't affect the readings themselves, it does "squish" the graph in its X-axis. - My graph lines up with the graph from Prusa because I had already printed some filament off it (which stretches my graph back into shape). That's also why it seems too mismatch at the start of the graphs. - The way I calculate un-roundness is not the same as what Prusa uses to measure ovality. The two values are not comparable. - The sensors themselves are way exceeding my expectations, but I've identified a few spots that can still be improved. I'll rework the design and publish it as CC-0 when I know it's done. - Filament winding was a massive challenge. Thinking about putting an automated winder arm on there at some point - unless there's already better solutions out there than that? But overall, I'm not just impressed by how well the setup worked, but also by how well these filaments are made!
Have you thought about using pairs of light sources and filtered photo transistors as sensors? With a wavelength that is absorbed by all filaments this should work as a diameter sensor without moving parts. The filters are important if the filament has a fluorescent dye in it.
Please do ones for Amazon basics, polymaker, and more protopasta. I'd love to see how different and more expensive filaments vary but also the cheapest reasonable quality like amazing basics. P.s. I miss your filoween episodes sooo much! I love this return to filament testing and I hope it stays!
I was thinking about point 1. It's probably not worth the effort to fix, but you could feed through an old extruder gear and wind with a spring loaded spool and motorized winder with a stop switch when the spring is tensioned. This would give you a constant speed.
But why don't you just order stack of ones if you're jealous? I mean very basic profiles like 2020 or 4040 are really dirt cheap per meter if you do some browsing. I have about I guess 6 meters on my stock all the time and as said it didn't cost much.
@@jothain mitsumi 2020 material, 75 day ship right now. With the CNY, it could be months before materials arrived even if ordered today. I have some 2020 arriving soon, but it took some digging to find stock. Nice pile of stock you have Tom. :p
Same here ☺️ it’s not as easy as it looks. Ofc you can just follow the basics to make filament (Pellets+ colorant) but I am sure we need more additives to make higher quality. Any luck in finding the almost perfect composition?
@@rastyle11 So far, after many modifications, I have a well-functioning extruder. For several weeks I have been installing the entire further process, cooling, measuring, filament stresses and filament winding. Today I start preparing electronics and programming all the regulators at the same time.
@@ukaszczupakstudia3085 that cool. Hope you can make it 😁. I am more into searching about the composition of the raw materials to make filament. Yes the diameter is important but also the additives (Plasticizers, Impact modifiers, lubricants etc) to make a better quality. I still can’t figure that out.
@@Trent-tr2nx At the moment, I do not want to spend tens of thousands in a project that may not work, so far it is at the threshold of thousands. I want to safely invest in the machine, and if it works very well then I'll start investing in sensors etc. At the moment, I use a dial gauge with an accuracy of 0.001mm.
I had been working on a filament diameter sensor that used optical mouse parts, but this is more practical. The thing is, I have extensive experience with Hall-effect sensors, and am a bit confused why I didn't start there in my design. Doh! My initial plan was to integrate real-time filament diameter sensing with the Klipper firmware. However, the overall quality improvement across the entire 3D printing ecosystem improved faster than my project was progressing, making Klipper much less of a need. I finally shelved my project when I got better at performing extrusion tests that showed filament diameter was NOT a significant factor compared to all the others. For example, filament feed accuracy made the largest contribution, particularly when the hobbed gear teeth get filled with filament. Nozzle quality also makes a difference. It's not just nozzle diameter errors: I think the smoothness of the passage to the outlet is also a factor. The extrusion tests I performed worked backwards, allowing for and eliminating measured factors to determine how much was left to be accounted for by things not yet measured. The amount left that could be due to variations in filament diameter were too small to be worth measuring! Those nozzles, though. What a mess, given that I use cheap ones. What I'd like to try next is to get smaller nozzles then polish them to the next larger size. Thinking of using thread and jeweler's rouge, but haven't tried anything yet mainly because of measurement issues: How will I know when to stop polishing? What I may do is settle for polishing until the ID is "smooth enough", then back-calculate the actual final diameter.
Now this is more like it! Great content Tom. It's really nice to see more making as opposed to just the same-old printing and reviewing. Now, how about a video showing us the end-to-end process and tools you used to get those PCBs designed and made?
I just want to say, in only a few minutes into your video and I decided to subscribe simply because of the organizational detail you put into your workshop! Outstanding!
From my experience on modding the hangprinter. Spool winding improves if theres less than 1º-2º between top and bottom of winding. Just make sure the first layer is correct, the rest just spools up nicely.
Would be interesting to see eSun filament tested with this machine, it's the cheapest I can get around here, but from what I can tell it's fine. Would be interesting to see how good/bad it actually is.
@@renevile There are cheap filament brands with very visible diameter tolerances. I would definitely buy a sensor that could mostly eradicate the differences in print quality between cheap filament and not so cheap filament.
It'll eventually be incorporated into newer machines i guarantee it. Much like auto bed level, filament diameter sensors will be able to adjust on the fly. No reason why something like this couldn't be achieved and achieved soon.
I was talking about that maybe 6 years ago. I even suggested it to Joseph Prusa when I met at Bay Area Maker Faire, but he wasn't convinced. My idea was to use linear image sensors to scan the filament in two axes.
I never saw cheap "no name" filament, but I do have my suppliers of inexpensive filaments in Europe: Devil Design and Azurefilm. I get PETG from Devil and A85 TPU from Azure.
If you fancy experimenting with the arrangement of hall sensor and magnet, there's a more sensitive configuration where either a thin magnet is placed edge-on to the sensor, or a pair of magnets used side by side. Either way, there is a very sharp transition from north to south. What's more, the response is nearly perfectly linear at the crossover point. This sort of configuration has been used in seismometers, and I once used it in a dilatometer which managed about 10nm resolution.
Trolleys for reeling garden hoses have a simple mechanism for evenly rolling the hose - a rod with a bi-directional thread and a hose guide wheel on it (the wheel changes direction when it reaches the end, the same at the other end). Similar mechanism could be used for filament winding.
would be cool to compare the cheapest filament you can find and the most expensive, and the cheapest reccomended filament (imo yoyi) Edit: seems I got lucky on pricing with yoyi filament, so OWL filament seems to unanimously be cheapest
Yeah definitely. The Amazon house brand and the direct from China brands, would be interesting also. There aren't that many places in the world that have the extruder plant to make these filaments. who they are and where they are might be difficult to identify in China but in the US and Europe probably not so hard to put your finger on what plant has what level of quality.
Like most 3D print youtubers Tom refuses to acknowledge the mere existence of cheap filament. BTW: Yoyi costs 40€ a spool. I pay 17-20€ for precise filament from Sunlu or eSun and 11-14€ for the cheapest stuff from OWL/Filamentwerk.
@@MetalheadAndNerd +1, nobody ever talks about cheap filament but they're probably the most used. Yeah filament is nice but even cheap filament is expensive, but I won't spend the double, even if it can be a bit better.
i am almost positive there would not be a big enough difference to even talk about. if one could magically go back in time and get a roll of filament from the 2016 ish lol then you would get your socks knocked off.
@@patprop74 There are visible differences. But the question is: Do I care? I do lots of my prints with 0.3mm layer height, 80mm/s outer wall speed and 120mm/s infill and inner wall speed. I don't care if the walls are not perfectly smooth since at these speeds there are other artifacts as well.
Watching an assembly it is incredible how nice music can be mixed using basic two spool deck player ;). The topic just hit my problems and thinkering. Great!
MASTERPIECE - wow that’s the most impressive project around 3d-Printing I have seen so far. Not solely the project itself, also the documentation and video quality is outstanding - CONGRATULATIONS Thomas ⭐️⭐️⭐️⭐️⭐️
I once used filament that a colleague of mine created out of pure pla from a chemistry supply store. As he did it by hand, the diameter was all over the place. I ended up cutting the filament into pieces with similar diameter, measured it with calipers and scaled the extrusion multiplier in my slicer to compensate for the diameter. Then I fed the short pieces (like 20cm each) one after the other into the printer. Fortunately it was only for a few test prints, and it only cost me half an afternoon. Good times ;)
Great test and ingenious testing rig. Kudos. Yes, I had problems with one spool of PLA. One 1kg spool of Anycubic I got last year gave me trouble. It managed to get stuck(!) in my Ender 3 Pro's regular bowden tubing. Most of it was fine but it exceeded the inner diameter of my tubing in spots. I even had to use pliers in order to get it out. TBF, that was one spool in five, but still...
Very impressive. Having Prusa's data to compare as an independent verification adds a level of validity that makes this worth some serious study. You are now positioned to do some interesting filament analysis. Testing the effects of humidity and drying systems on filament? To answer your inquiry, the only problem I've ever had was after replacing the bowden tube on my Ender 3 Pro. I think the tubing was a little too tight. During a really humid month, I had a spool of ASA that kept jamming. Switching out to some Capricorn tubing fixed the issue, as well we adding a heater to my cabinet, to keep the humidity down.
I have seen quite a few filament spools where the filament is rotated and jagged,that can also make almost square sections,not just oval, usually cheaper brands, even local german, not even the chinese manufacutrers
I had in August a Material4Print ASA Black spool with a measured diameter of 2.18 instead of 1.75 on three spots. Got a replacement and even there at some point it got stuck but didn’t measure. Nonetheless, two others were absolutely fine (did not get stuck in the ptfe tube at least). Customer service did not reveal why that happened, just said that I am the only one at the first time I wrote to them
This is the best video I have seen from you in over a year, great engineering, it was very enjoyable watching you put this all together and have it work.
I've had big problems with Eryone Sparkly Silver PLA, Which has a claimed 50 micron tolerance, however i've found lumps up to 2mm in diameter which is causes the filament to jam at the extruder. I wasted nearly half a roll trying to print with it. I came up with a dual purpose filament jam/runout sensor that uses a single microswitch to pause the printer if a lump is detected.
I have some old filament (a clear nylon) that got very oval over time. When it was new, it would print just fine, but after a few years, it's now so oval (checked with calipers) that i can't feed it thru a piece of teflon tube anymore. Interesting device you have built tho, all it needs is a better filament winder with an extra axis that slowly guides the winding up and down along the width of a spool. And having a pickup that reads the length of filament running thru the sensors to give you an absolute position might be another nice addon idea.
I thought of doing this inline for extrusion multiplier adjustment in real time using linear image sensors (one in each axis). Just needs an opposing LED light source with diffuser and do a binary threshold on the image. Joseph Prusa wasn't convinced when I suggested it to him maybe 6 years ago.
Regarding the question at the end: I mostly use the cheapest PLA filament for my prints, which is usually from Filamentwerk/I-Filament/OWL. Their filament often has some diameter variations but only maybe 1 out of 30 spools is really bad and the filament gets stuck in my generously sized bowden tube. If you like I can send the next bad spool to you.
13:22 Just WOW!!!!! Thomas Sanladerer... I'm very very proud of yourself. The filament size sensor you design is truly (I've no words to say how impress I am). Don't know if this is a German thing, but I would be so excited/demonstrative if I had got that level of precision at that price point! And... You put your design free of right And... We can build it for under 5$ All heroes don't wear cape.... some wear hall-effect sensor!
Interesting setup and measurement, very nice. although you commented that your numbers kinda match Prusa's, I still wonder if the lack of tension control on the feeding spool has any effects. Just for ref, the same setup you created to measure diameter can be used as a tension measurement system; an arm that swivels pushed by a spring, and linear hall sensor to measure arm position. To control tension, two motors, the existing one that pulls, and another one that drives the feeder. Then a ""simple"" control loop that maintains the tension arm in the same position by adjusting the feeder motor speed. Pulling motor at constant (user defined) speed. I think this might also help use less force in the diameter measuring device (softer spring), so it does not compress the filament.
Hitting it out of the park as usual. Between you and Stefan @ CNC Kitchen you guys are doing great technical work for the 3d printing community, go Germany.
I am so jealous of all the materials (Al extrusions and hardware) you have in your shop. I have so many ideas for designs and would never leave the shop.
Great work. I have been thinking about the same thing. Attach it to the printer and then have the firmware automatically adjust the extrusion speed based on the actual diameter. However considering your results it sounds like it would not be worth the effort. Honestly I use whatever filament is the lowest cost and have never had any issues. Seems like pretty well all the manufacturers have increased quality. I am sure many of those are not within the 20, instead up to 50 though...
Hi Tom, I'm not sure if it's been mentioned yet, but generally speaking if you want to design a sensor for high accuracy you want the mechanical design to follow Abbe's principle. It is worth looking up if you intend to do a further hardware redesign, might improve your accuracy!
Just have to say that I love your hoodie! Lol. I just bought my first 3d printer and got it set up thanks to yours and a few other's videos. Thanks for the content. I have learned so much about 3d printing but still need to learn soooo much more!
Just a thought about the calibration scheme: wouldn't using magnetic drill bits as standards have some effect on the hall sensor readings, compared to nonmagnetic filament? Since any offset would be consistent, ovality readings might still be good, but avg diameter might not be.
Yes, steel drill bits are inherently ferromagnetic, but from what I've seen, that doesn't affect the measurement (in any meaningful way). Even holding another magnet a couple of cm away from the sensor doesn't change the output.
@@MadeWithLayers You mean ferromagnetic. Actually the filament is probably diamagnetic (it could be paramagnetic). Ferromagnetic materials are drawn to a magnet. Diamagnetic materials are repelled, usually very very weakly.
Nice setup. From my experience I think that the filament diameter being consistent are allot more important then most users or manufacturer think. I have had good result with addnorth filament. Removing the need for constant measuring the filament diameter
Love it! I have one spool, (I think it's the AMZ3D but it's very old) I can't use because every couple of meters or so it goes large enough to jam. It would be easy enough to add another axis on the pickup spool to wind it evenly
Of all the spools I had/have, some were really bad when it comes to diameter consistency : eSun PLA+ (light blue). Besides debatable winding, there were so much variations in diameter the filament did struggle to extrude properly... Leading eventually to print failure after only a few layers. Also, a Filatech nylon spool had the very same issues.
Quick thought/suggestion: I know that there are many different varieties of 608 bearings, so they're all over the place. Most 608 bearings I've seen have quite a bit of internal clearance, with seven balls spaced around the race. Because of the internal clearance, I would expect there to be a "bump" every time a ball rolls by (inside the bearing). Some 608 bearings have pre-load in them, so they have much reduced "clearance." I think I heard one skateboard reviewer saying that Lucky ABEC7 brand bearings have the least-clearance / most-preload he's seen. I think their ABEC7 versions are no longer manufactured, but you might check Lucky's other versions. Also, you could try testing a length of precision drill-rod and see if there is any periodic error that matches the spacing of the bearing balls. Finally, if you have a friend who is a machinist, they may have a micrometer with a measuring head designed for measuring the thickness of pipes. You *might* be able to use that to measure the "thickness" of the bearing directly over a ball, and compare that to the "thickness" between balls. But... it might also be really tricky unless you have excellent micrometer technique, because the balls and races can all move around.
I’ve been interested in something like this, but wasn’t sure how to go about it. Looks like I’ve got a great starting point now. Excellent!! Thank you!!!
I don't buy my filament from big company, i found a local (Canada) and buy there cheap econo line of product. I personal never had any problem with filament. I'm happy that you did this video and not me. My interrogation is; what is the impact on final print quality if the filament is more or less diameter accurate. i print big part with a 0.4mm nozzle?
Great project but I have a question: with the increase in the amount of filament on the towing spool does not increase the radius and therefore the tangential speed? If the frequency of detection of the diameter remains unchanged, is there not a risk of reducing the accuracy of the measurement?
I had a supplier that had a few problems and the filament varied from 1.74 to 1.81 but they apparently fixed the machine and are now more careful because i haven't had any problems since
for implementation into printers, I'd be curious to see a version of the diameter sensor that has three levers measuring the same space at the same time, that way it's a bit easier to get readouts in real time for the printer. not fully sure how I'd go about doing that however.
Awesome!!! We are also working to adapt to a future industrial printers a system to equalize the flow and solve one of the biggest problems for the accuracy of FDM printers.
The testing is great but seeing a bit of your workshop was even better, lol. I'm super jealous that you have all that raw stock of AL extrusions and nicely sorted fasteners.
Awesome test! I think the bumpiness definitely effects the reading. The free area within the sensor should be as short as possible. Maybe it also helps a bit if the source spool isn't spinning completely free, so you get a bit of tension in the filament. And for winding: you might need a second stepper increasing Z by filament diameter by each rotation of the winding stepper, and the return the same way after every layer.
I'm wondering if the ferrous metal in the drill bits you were using for calibration may have disturbed your readings since it's a Hall sensor. While it's not likely to be a huge effect on the readings, it's not likely to be zero and you're shooting for precision. Maybe it would be a good idea to calibrate using a magnetically inert material instead?
As you're driving the reel with CNC anyway, you could add an axis to lay the filament neatly onto the spool. Do you have any feel for how much skew is introduced to the results due to non-linearity of the feed speed caused by the steadily increasing diameter? I'm assuming the Prusa data is linear as it's the output from the extruder?
The (re-)winding machine alone is already super interesting. I talked with some twitter friends recently about "group buying" interesting filaments and then sending each other "samples" or 250g spools.
Really awesome project. Thanks. From using a winch I learned a small amount of drag will help the plastic spool neater also maybe purring it on its side? Hope I don't come across as being critical. Big fan
Now imagine if that was actually hooked into the printing process and automatically adjusted flow rates on the go to compensate for the change in diameter!
As far as I understand it, Marlin expects an analog input currently (1mV = 1um), which my sensor is designed to output. However, I would much prefer I2C, as the sampling is already done on the ATTiny. No need to go back to and from analog again.
@@MadeWithLayers As soon as there is a supply for a sensor at the horizon the software support will be ready within a few days. Marlin 2 is wonderfully modular. I almost wrote an extension for an external fam controller to have proper control over all fans with an SKR 1.4.
That was something that was widely talked about in the days of RepRap when we were all building our own printers instead of buying china made printers lol Some companies like mosaic used the idea of that and made the palette.
You could use compliant mechanisms to reduce the cost of the sensor and actually increase the accuracy/repeatability since you're removing any errors from one of the rollers. You could also replace the second roller bearing with a halfpipe PTFE tube, which would be a lot cheaper and could possibly increase the accuracy (depending on the quality of the roller bearing being used, but given we want to minimize cost I'd say many people are going to use 'low grade' roller bearings, thus a PTFE tube sliding on the filament will more accurate. You can also use photodiodes/LED's instead of hallsensors which would also reduce cost, and make the part non-magnetic which can be good for some filament.
Perfect you nailed it. You put a lot of effort in that project. Asking myself if a little bit tension on the spool getting unwind will help with the winding on the new spool?
Those sensors are really cool. I can see farms maybe using them to monitor filament without costing a pretty penny. Also, it can be really good for future reviews of new companies producing filaments if any. My only problem with Diameter has been the absolute Cheapest Black PLA on Amazon a while back, and I wasn't too miffed about it. PLA+ feels so nice to use.
The inconsistency might also come from the ball bearings. I wonder how it would fair if you use teflon tube as a sliding surface to measure the thickness.
Great video!!!! Would love to see a follow-up video measuring the diameter of the the same spools after storing them on ambient air for a few days, to see how absorbed moisture is going to affect the quality of the filament.
I recently had a few issues with Purefil PLA-filament (a Swiss filament company), which states tolerances of 0.05mm but I measured a bit more than 0.1mm by using a Mitutoyo micrometer, which should be quite accurate. If you could measure a spool from them, I would be very interested in that.
I have ESUN White Standard PLA and for some reason my vertical walls are inconsistent. At first I though it was the setting but after switching out filaments my vertical walls were perfect. Not sure if it's due to inconsistency's by I just cannot get decent prints with it. Other ESUN filaments seem fine, might just be the one roll.
Consider a rotary encoder wheel samwhiched on the filament itself to measure position in the spool rather than measuring spool angular position. This automatically accounts for the diameter of the spool growing as it takes up yarn, and removes the need for precise control of the takeup spool.
Awesome video Tom, really great setup! I see all of your readings put the average diameter of the filament at approx 1.7, rather than the 1.75mm, do you intend to do more calibration on diameter? Since your data and Prusa's data lines up so well, and as you say, Prusa will be using some top-notch laser sensors, you could potentially use their data to further calibrate the diameter measurements of your sensors. I do think a more accurate reading on the diameter would make your setup even more powerful, particularly if you do plan to use it to actively compensate for flow rate on a 3D Printer. I have been involved with filament production for the last few months and it has been quite a learning curve! One of my key takings has been that spool consistency is also incredibly important. For example, if a filament holds a +/- 20 micron tolerance per spool but the average diameter fluctuates, the results between successive spools will make for more noticeable under/over extrusion. From this perspective, I would suggest that the average diameter is actually more important than the tolerance of the spool itself (within reason). While obviously important, I do think that tolerance is something a lot of print users unnecessarily obsess over and there are many more important factors at play when it comes to getting the best prints. A prime example of this being the 'print your own filament' videos that have cropped up, where the tolerance is likely to vary quite wildly and yet some great prints have been produced from this process (ref. CNC Kitchen's Bency with PC-ABS). Maybe a piece of printed filament is something you might even like to test with your new measurement setup. Keep up the good work! I'm releasing my filament soon, will have to send you a spool. Callum
This is a very cool testing rig. I love the use of hall-effect sensors here, very clever! I haven't really had any issue personally with filament inconsistencies, but it would be interesting to compare two spools of the same filament, but from different batches. Thanks for the video tom, I really like your experiment videos! 🧡💙
Cool project, one question though . When calibrating the filament with a drill bit, wouldnt that throw your readings off a little .Since the metal drill bit would couple more magnetic flux then using a non-metallic object. Or does that not matter though since you are measuring the magnitude of change in magnetic field.
Recently I've had an issue with DevilDesign PET-G - after 2-3 1h prints, the diameter changed from ~1.71 at the beginning of the spool to 1.74. measured with a micrometer
What are the boards you hook up to the hall sensors? I assume the boards are what allows the I2C communication? Can you hook up anything to these boards or are they specific to the hall sensor?
I've had problems with several filaments so far, but the diameter was none of the causes. I've had a blue night-glow PLA from Amolen that almost didn't glow, I had a blue semitransparent PLA that had rigid sections where it broke like glass as it pulls through the filament end sensor, I had several cheap PLAs off Amazon that were so crappily wound that they had 45 degree kinks in them or were so tightly wound and/or stored so warm that layers on the spool fused together. So far, my best experiences were with the PLA from Anycubic, with PrimaCreator EasyPrint PLA and Janbex PLA. Basicfil is so-so, some spools were neatly wound, others were rather messy, which suggests they are reselling different sources.
Couple notes on the results:
- I'm currently not tracking how quickly filament is being pulled through the sensors. While this won't affect the readings themselves, it does "squish" the graph in its X-axis.
- My graph lines up with the graph from Prusa because I had already printed some filament off it (which stretches my graph back into shape). That's also why it seems too mismatch at the start of the graphs.
- The way I calculate un-roundness is not the same as what Prusa uses to measure ovality. The two values are not comparable.
- The sensors themselves are way exceeding my expectations, but I've identified a few spots that can still be improved. I'll rework the design and publish it as CC-0 when I know it's done.
- Filament winding was a massive challenge. Thinking about putting an automated winder arm on there at some point - unless there's already better solutions out there than that?
But overall, I'm not just impressed by how well the setup worked, but also by how well these filaments are made!
Have you thought about using pairs of light sources and filtered photo transistors as sensors? With a wavelength that is absorbed by all filaments this should work as a diameter sensor without moving parts. The filters are important if the filament has a fluorescent dye in it.
Do you need some filament with bigger diameter tolerances for testing?
Does using a drill bit shaft affect your hall sensor calibration in any way, cause it's steel (seams not the case)
Please do ones for Amazon basics, polymaker, and more protopasta. I'd love to see how different and more expensive filaments vary but also the cheapest reasonable quality like amazing basics. P.s. I miss your filoween episodes sooo much! I love this return to filament testing and I hope it stays!
I was thinking about point 1. It's probably not worth the effort to fix, but you could feed through an old extruder gear and wind with a spring loaded spool and motorized winder with a stop switch when the spring is tensioned.
This would give you a constant speed.
Not gonna lie, I am jealous of your stack of aluminium profiles.
SAME
Me too! I thought "damn that would be nice to have"
But why don't you just order stack of ones if you're jealous? I mean very basic profiles like 2020 or 4040 are really dirt cheap per meter if you do some browsing. I have about I guess 6 meters on my stock all the time and as said it didn't cost much.
Also jealous that where Tom lives, there's no need to deal with both metric AND imperial profiles and hardware. Grrrrrr!
@@jothain mitsumi 2020 material, 75 day ship right now. With the CNY, it could be months before materials arrived even if ordered today. I have some 2020 arriving soon, but it took some digging to find stock. Nice pile of stock you have Tom. :p
love the editing in this video vs all the others ive seen so far. you're killin it!
Yup! Spinning the spools like a DJ was awesome! Hahahaha nice!
Yeah i noticed that too :)
Agreed, editing change is welcome. I like seeing the build up process to the final project too. Great work as always.
For months I have been building a production line for the production of filament, this is the video I needed :D
Same here ☺️ it’s not as easy as it looks. Ofc you can just follow the basics to make filament (Pellets+ colorant) but I am sure we need more additives to make higher quality.
Any luck in finding the almost perfect composition?
@@rastyle11 So far, after many modifications, I have a well-functioning extruder. For several weeks I have been installing the entire further process, cooling, measuring, filament stresses and filament winding. Today I start preparing electronics and programming all the regulators at the same time.
@@ukaszczupakstudia3085 check out how prusa does the diameter measurement for Prusament. I believe their system is all optical
@@ukaszczupakstudia3085 that cool. Hope you can make it 😁. I am more into searching about the composition of the raw materials to make filament. Yes the diameter is important but also the additives (Plasticizers, Impact modifiers, lubricants etc) to make a better quality. I still can’t figure that out.
@@Trent-tr2nx At the moment, I do not want to spend tens of thousands in a project that may not work, so far it is at the threshold of thousands. I want to safely invest in the machine, and if it works very well then I'll start investing in sensors etc.
At the moment, I use a dial gauge with an accuracy of 0.001mm.
This is incredible content. Tom is a genius. His results scaled on to the prusa results is unbelievably good
Love the design of the sensor Tom.
It’s an excellent project 👍
I had been working on a filament diameter sensor that used optical mouse parts, but this is more practical. The thing is, I have extensive experience with Hall-effect sensors, and am a bit confused why I didn't start there in my design. Doh!
My initial plan was to integrate real-time filament diameter sensing with the Klipper firmware. However, the overall quality improvement across the entire 3D printing ecosystem improved faster than my project was progressing, making Klipper much less of a need.
I finally shelved my project when I got better at performing extrusion tests that showed filament diameter was NOT a significant factor compared to all the others. For example, filament feed accuracy made the largest contribution, particularly when the hobbed gear teeth get filled with filament.
Nozzle quality also makes a difference. It's not just nozzle diameter errors: I think the smoothness of the passage to the outlet is also a factor.
The extrusion tests I performed worked backwards, allowing for and eliminating measured factors to determine how much was left to be accounted for by things not yet measured. The amount left that could be due to variations in filament diameter were too small to be worth measuring!
Those nozzles, though. What a mess, given that I use cheap ones. What I'd like to try next is to get smaller nozzles then polish them to the next larger size. Thinking of using thread and jeweler's rouge, but haven't tried anything yet mainly because of measurement issues: How will I know when to stop polishing? What I may do is settle for polishing until the ID is "smooth enough", then back-calculate the actual final diameter.
You will soon make the million subs.
Plot twist: Tom's full name is Tomato
Now this is more like it! Great content Tom. It's really nice to see more making as opposed to just the same-old printing and reviewing. Now, how about a video showing us the end-to-end process and tools you used to get those PCBs designed and made?
That build montage was awesome. Really enjoy that kind of content and the result looks great!
This is the quality content I subscribe for.
I just want to say, in only a few minutes into your video and I decided to subscribe simply because of the organizational detail you put into your workshop! Outstanding!
From my experience on modding the hangprinter. Spool winding improves if theres less than 1º-2º between top and bottom of winding. Just make sure the first layer is correct, the rest just spools up nicely.
Would be interesting to see eSun filament tested with this machine, it's the cheapest I can get around here, but from what I can tell it's fine. Would be interesting to see how good/bad it actually is.
Same with Printed Solid's Jessie PLA. I had a couple of great spools but this latest one I bought from them kept causing extruder skipping.
I'd like to see Devil Design and also Azurefilm filaments to be tested.
Since Marlin already has support for a filament diameter sensor this could be the next big feature in FFF printers.
I kinda feel the sensor is noisier than the actual filament diameter...
@@SianaGearz That would be easy to filter out.
@@renevile There are cheap filament brands with very visible diameter tolerances. I would definitely buy a sensor that could mostly eradicate the differences in print quality between cheap filament and not so cheap filament.
It'll eventually be incorporated into newer machines i guarantee it. Much like auto bed level, filament diameter sensors will be able to adjust on the fly. No reason why something like this couldn't be achieved and achieved soon.
I was talking about that maybe 6 years ago. I even suggested it to Joseph Prusa when I met at Bay Area Maker Faire, but he wasn't convinced.
My idea was to use linear image sensors to scan the filament in two axes.
15:24 well now I REALLY want to know if “cheap” non brand name filament is any good. 🧐
I never saw cheap "no name" filament, but I do have my suppliers of inexpensive filaments in Europe: Devil Design and Azurefilm. I get PETG from Devil and A85 TPU from Azure.
If you fancy experimenting with the arrangement of hall sensor and magnet, there's a more sensitive configuration where either a thin magnet is placed edge-on to the sensor, or a pair of magnets used side by side. Either way, there is a very sharp transition from north to south. What's more, the response is nearly perfectly linear at the crossover point. This sort of configuration has been used in seismometers, and I once used it in a dilatometer which managed about 10nm resolution.
Trolleys for reeling garden hoses have a simple mechanism for evenly rolling the hose - a rod with a bi-directional thread and a hose guide wheel on it (the wheel changes direction when it reaches the end, the same at the other end). Similar mechanism could be used for filament winding.
Next-level content and providing a way for the community to test it ourselves as well. Thank you for your hard work.
would be cool to compare the cheapest filament you can find and the most expensive, and the cheapest reccomended filament (imo yoyi)
Edit: seems I got lucky on pricing with yoyi filament, so OWL filament seems to unanimously be cheapest
Yeah definitely. The Amazon house brand and the direct from China brands, would be interesting also. There aren't that many places in the world that have the extruder plant to make these filaments. who they are and where they are might be difficult to identify in China but in the US and Europe probably not so hard to put your finger on what plant has what level of quality.
Like most 3D print youtubers Tom refuses to acknowledge the mere existence of cheap filament.
BTW: Yoyi costs 40€ a spool.
I pay 17-20€ for precise filament from Sunlu or eSun and 11-14€ for the cheapest stuff from OWL/Filamentwerk.
@@MetalheadAndNerd +1, nobody ever talks about cheap filament but they're probably the most used. Yeah filament is nice but even cheap filament is expensive, but I won't spend the double, even if it can be a bit better.
i am almost positive there would not be a big enough difference to even talk about. if one could magically go back in time and get a roll of filament from the 2016 ish lol then you would get your socks knocked off.
@@patprop74 There are visible differences. But the question is: Do I care?
I do lots of my prints with 0.3mm layer height, 80mm/s outer wall speed and 120mm/s infill and inner wall speed. I don't care if the walls are not perfectly smooth since at these speeds there are other artifacts as well.
Watching an assembly it is incredible how nice music can be mixed using basic two spool deck player ;).
The topic just hit my problems and thinkering. Great!
MASTERPIECE - wow that’s the most impressive project around 3d-Printing I have seen so far. Not solely the project itself, also the documentation and video quality is outstanding - CONGRATULATIONS Thomas ⭐️⭐️⭐️⭐️⭐️
I love this kind of high-quality DIY objective measurement of commercial products, Outstanding work, Tom!
I once used filament that a colleague of mine created out of pure pla from a chemistry supply store. As he did it by hand, the diameter was all over the place. I ended up cutting the filament into pieces with similar diameter, measured it with calipers and scaled the extrusion multiplier in my slicer to compensate for the diameter. Then I fed the short pieces (like 20cm each) one after the other into the printer. Fortunately it was only for a few test prints, and it only cost me half an afternoon. Good times ;)
Great test and ingenious testing rig. Kudos.
Yes, I had problems with one spool of PLA. One 1kg spool of Anycubic I got last year gave me trouble. It managed to get stuck(!) in my Ender 3 Pro's regular bowden tubing. Most of it was fine but it exceeded the inner diameter of my tubing in spots. I even had to use pliers in order to get it out. TBF, that was one spool in five, but still...
really wonder if filaments will change in diameter after they absorb some good amount of moisture
Definitely a good setup to test that. Dunk a spool and measure it, or measure a spool before and after dehydrating
Very impressive. Having Prusa's data to compare as an independent verification adds a level of validity that makes this worth some serious study. You are now positioned to do some interesting filament analysis. Testing the effects of humidity and drying systems on filament?
To answer your inquiry, the only problem I've ever had was after replacing the bowden tube on my Ender 3 Pro. I think the tubing was a little too tight. During a really humid month, I had a spool of ASA that kept jamming.
Switching out to some Capricorn tubing fixed the issue, as well we adding a heater to my cabinet, to keep the humidity down.
I have seen quite a few filament spools where the filament is rotated and jagged,that can also make almost square sections,not just oval, usually cheaper brands, even local german, not even the chinese manufacutrers
I don‘t comment often on videos but I have to say that this was some really nice engineering work and a good scientific approach! Good job Tom!
I had in August a Material4Print ASA Black spool with a measured diameter of 2.18 instead of 1.75 on three spots. Got a replacement and even there at some point it got stuck but didn’t measure.
Nonetheless, two others were absolutely fine (did not get stuck in the ptfe tube at least). Customer service did not reveal why that happened, just said that I am the only one at the first time I wrote to them
This is the best video I have seen from you in over a year, great engineering, it was very enjoyable watching you put this all together and have it work.
I've had big problems with Eryone Sparkly Silver PLA, Which has a claimed 50 micron tolerance, however i've found lumps up to 2mm in diameter which is causes the filament to jam at the extruder. I wasted nearly half a roll trying to print with it.
I came up with a dual purpose filament jam/runout sensor that uses a single microswitch to pause the printer if a lump is detected.
I have some old filament (a clear nylon) that got very oval over time. When it was new, it would print just fine, but after a few years, it's now so oval (checked with calipers) that i can't feed it thru a piece of teflon tube anymore.
Interesting device you have built tho, all it needs is a better filament winder with an extra axis that slowly guides the winding up and down along the width of a spool. And having a pickup that reads the length of filament running thru the sensors to give you an absolute position might be another nice addon idea.
I thought of doing this inline for extrusion multiplier adjustment in real time using linear image sensors (one in each axis). Just needs an opposing LED light source with diffuser and do a binary threshold on the image.
Joseph Prusa wasn't convinced when I suggested it to him maybe 6 years ago.
That build edit is sooo amazing 😄👍 Awesome music choice too ^^
I thought about measuring filament in 3 planes literally yesterday evening. Good timing Thomas. Thank you.
Regarding the question at the end: I mostly use the cheapest PLA filament for my prints, which is usually from Filamentwerk/I-Filament/OWL.
Their filament often has some diameter variations but only maybe 1 out of 30 spools is really bad and the filament gets stuck in my generously sized bowden tube.
If you like I can send the next bad spool to you.
13:22 Just WOW!!!!! Thomas Sanladerer...
I'm very very proud of yourself. The filament size sensor you design is truly (I've no words to say how impress I am).
Don't know if this is a German thing, but I would be so excited/demonstrative if I had got that level of precision at that price point!
And... You put your design free of right
And... We can build it for under 5$
All heroes don't wear cape.... some wear hall-effect sensor!
Interesting setup and measurement, very nice. although you commented that your numbers kinda match Prusa's, I still wonder if the lack of tension control on the feeding spool has any effects.
Just for ref, the same setup you created to measure diameter can be used as a tension measurement system; an arm that swivels pushed by a spring, and linear hall sensor to measure arm position. To control tension, two motors, the existing one that pulls, and another one that drives the feeder. Then a ""simple"" control loop that maintains the tension arm in the same position by adjusting the feeder motor speed. Pulling motor at constant (user defined) speed. I think this might also help use less force in the diameter measuring device (softer spring), so it does not compress the filament.
Hitting it out of the park as usual. Between you and Stefan @ CNC Kitchen you guys are doing great technical work for the 3d printing community, go Germany.
I am so jealous of all the materials (Al extrusions and hardware) you have in your shop. I have so many ideas for designs and would never leave the shop.
Great Idea. What I miss in this build is a solution to wind up the tested Filament correctly and remove fails (knots) from the original spule.
Great work. I have been thinking about the same thing. Attach it to the printer and then have the firmware automatically adjust the extrusion speed based on the actual diameter. However considering your results it sounds like it would not be worth the effort. Honestly I use whatever filament is the lowest cost and have never had any issues. Seems like pretty well all the manufacturers have increased quality. I am sure many of those are not within the 20, instead up to 50 though...
1:34
"we're gonna see how well they stack up"
Me: looks at the stack of filaments
I'd say they stack up pretty well
Fascinating video and not something I have considered or seen before I suppose because I’ve never had a diameter problem. Thanks I enjoyed this
Hi Tom, I'm not sure if it's been mentioned yet, but generally speaking if you want to design a sensor for high accuracy you want the mechanical design to follow Abbe's principle. It is worth looking up if you intend to do a further hardware redesign, might improve your accuracy!
Just have to say that I love your hoodie! Lol. I just bought my first 3d printer and got it set up thanks to yours and a few other's videos. Thanks for the content. I have learned so much about 3d printing but still need to learn soooo much more!
Just a thought about the calibration scheme: wouldn't using magnetic drill bits as standards have some effect on the hall sensor readings, compared to nonmagnetic filament? Since any offset would be consistent, ovality readings might still be good, but avg diameter might not be.
He never said the drill bits were magnetic.
Yes, steel drill bits are inherently ferromagnetic, but from what I've seen, that doesn't affect the measurement (in any meaningful way). Even holding another magnet a couple of cm away from the sensor doesn't change the output.
@@MadeWithLayers You mean ferromagnetic. Actually the filament is probably diamagnetic (it could be paramagnetic). Ferromagnetic materials are drawn to a magnet. Diamagnetic materials are repelled, usually very very weakly.
Nice setup.
From my experience I think that the filament diameter being consistent are allot more important then most users or manufacturer think.
I have had good result with addnorth filament.
Removing the need for constant measuring the filament diameter
Love it! I have one spool, (I think it's the AMZ3D but it's very old) I can't use because every couple of meters or so it goes large enough to jam.
It would be easy enough to add another axis on the pickup spool to wind it evenly
Of all the spools I had/have, some were really bad when it comes to diameter consistency : eSun PLA+ (light blue). Besides debatable winding, there were so much variations in diameter the filament did struggle to extrude properly... Leading eventually to print failure after only a few layers.
Also, a Filatech nylon spool had the very same issues.
Quick thought/suggestion:
I know that there are many different varieties of 608 bearings, so they're all over the place. Most 608 bearings I've seen have quite a bit of internal clearance, with seven balls spaced around the race. Because of the internal clearance, I would expect there to be a "bump" every time a ball rolls by (inside the bearing).
Some 608 bearings have pre-load in them, so they have much reduced "clearance." I think I heard one skateboard reviewer saying that Lucky ABEC7 brand bearings have the least-clearance / most-preload he's seen. I think their ABEC7 versions are no longer manufactured, but you might check Lucky's other versions.
Also, you could try testing a length of precision drill-rod and see if there is any periodic error that matches the spacing of the bearing balls.
Finally, if you have a friend who is a machinist, they may have a micrometer with a measuring head designed for measuring the thickness of pipes. You *might* be able to use that to measure the "thickness" of the bearing directly over a ball, and compare that to the "thickness" between balls. But... it might also be really tricky unless you have excellent micrometer technique, because the balls and races can all move around.
I’ve been interested in something like this, but wasn’t sure how to go about it. Looks like I’ve got a great starting point now. Excellent!! Thank you!!!
I don't buy my filament from big company, i found a local (Canada) and buy there cheap econo line of product. I personal never had any problem with filament. I'm happy that you did this video and not me. My interrogation is; what is the impact on final print quality if the filament is more or less diameter accurate. i print big part with a 0.4mm nozzle?
Thomas, that sensor is brilliant! Thanks for sharing that! I'm gonna build a similar system that will run inline with my printer! So cool!
Could this be integrated onto a printer and used to compensate esteps on the fly? More importantly, would it help?
Yes, but actually no
@@MadeWithLayers why not?
Great project but I have a question: with the increase in the amount of filament on the towing spool does not increase the radius and therefore the tangential speed? If the frequency of detection of the diameter remains unchanged, is there not a risk of reducing the accuracy of the measurement?
I had a supplier that had a few problems and the filament varied from 1.74 to 1.81 but they apparently fixed the machine and are now more careful because i haven't had any problems since
for implementation into printers, I'd be curious to see a version of the diameter sensor that has three levers measuring the same space at the same time, that way it's a bit easier to get readouts in real time for the printer. not fully sure how I'd go about doing that however.
Consider adding a Level Wind mechanism to evenly distribute the filament onto the spool. It's the same mechanism used on bait caster fishing reels.
Could you test some Amazon basics pla
Awesome!!! We are also working to adapt to a future industrial printers a system to equalize the flow and solve one of the biggest problems for the accuracy of FDM printers.
The testing is great but seeing a bit of your workshop was even better, lol. I'm super jealous that you have all that raw stock of AL extrusions and nicely sorted fasteners.
That idea of a printer auto-adjusting the filament diameter compensation is such a good idea😁😁🦆👍👌👏
What an absolute cool test method! I'm very impressed!!!
The hall effect sensor is totally brilliant. I need to work with those more.
Awesome test! I think the bumpiness definitely effects the reading. The free area within the sensor should be as short as possible.
Maybe it also helps a bit if the source spool isn't spinning completely free, so you get a bit of tension in the filament.
And for winding: you might need a second stepper increasing Z by filament diameter by each rotation of the winding stepper, and the return the same way after every layer.
What is the piloted reamer /endmill at 4:25 ?
Loving this Thomas, Great Manufacturing Skills shown, I love your workshop! Love your Channel! Keep up the good work!
I'm wondering if the ferrous metal in the drill bits you were using for calibration may have disturbed your readings since it's a Hall sensor. While it's not likely to be a huge effect on the readings, it's not likely to be zero and you're shooting for precision. Maybe it would be a good idea to calibrate using a magnetically inert material instead?
Should we be changing the filament diameter in our slicer? As it looks like all filaments tested are lower than 1.75 mm.
As you're driving the reel with CNC anyway, you could add an axis to lay the filament neatly onto the spool.
Do you have any feel for how much skew is introduced to the results due to non-linearity of the feed speed caused by the steadily increasing diameter? I'm assuming the Prusa data is linear as it's the output from the extruder?
The (re-)winding machine alone is already super interesting. I talked with some twitter friends recently about "group buying" interesting filaments and then sending each other "samples" or 250g spools.
Really awesome project. Thanks. From using a winch I learned a small amount of drag will help the plastic spool neater also maybe purring it on its side? Hope I don't come across as being critical. Big fan
Now imagine if that was actually hooked into the printing process and automatically adjusted flow rates on the go to compensate for the change in diameter!
Marlin 2 already has this feature. Sitting there, waiting for someone to build a sensor.
As far as I understand it, Marlin expects an analog input currently (1mV = 1um), which my sensor is designed to output. However, I would much prefer I2C, as the sampling is already done on the ATTiny. No need to go back to and from analog again.
@@MadeWithLayers As soon as there is a supply for a sensor at the horizon the software support will be ready within a few days. Marlin 2 is wonderfully modular.
I almost wrote an extension for an external fam controller to have proper control over all fans with an SKR 1.4.
That was something that was widely talked about in the days of RepRap when we were all building our own printers instead of buying china made printers lol Some companies like mosaic used the idea of that and made the palette.
Marlin can do that already
You could use compliant mechanisms to reduce the cost of the sensor and actually increase the accuracy/repeatability since you're removing any errors from one of the rollers. You could also replace the second roller bearing with a halfpipe PTFE tube, which would be a lot cheaper and could possibly increase the accuracy (depending on the quality of the roller bearing being used, but given we want to minimize cost I'd say many people are going to use 'low grade' roller bearings, thus a PTFE tube sliding on the filament will more accurate. You can also use photodiodes/LED's instead of hallsensors which would also reduce cost, and make the part non-magnetic which can be good for some filament.
Perfect you nailed it. You put a lot of effort in that project.
Asking myself if a little bit tension on the spool getting unwind will help with the winding on the new spool?
Those sensors are really cool. I can see farms maybe using them to monitor filament without costing a pretty penny. Also, it can be really good for future reviews of new companies producing filaments if any.
My only problem with Diameter has been the absolute Cheapest Black PLA on Amazon a while back, and I wasn't too miffed about it. PLA+ feels so nice to use.
The inconsistency might also come from the ball bearings. I wonder how it would fair if you use teflon tube as a sliding surface to measure the thickness.
Great video!!!! Would love to see a follow-up video measuring the diameter of the the same spools after storing them on ambient air for a few days, to see how absorbed moisture is going to affect the quality of the filament.
One of the reasons why I love Prusament They don’t try to hide anything and put the tolerance of that exact spool on the box.
building montage with 80's style synth....classic
The montage music was amazing.
Man, always with some really good content!
By the way, love your sweater!
Have a look at the Lyman extruder, you’ll find a mechanism to help the filament lay flat during winding
I recently had a few issues with Purefil PLA-filament (a Swiss filament company), which states tolerances of 0.05mm but I measured a bit more than 0.1mm by using a Mitutoyo micrometer, which should be quite accurate. If you could measure a spool from them, I would be very interested in that.
I have ESUN White Standard PLA and for some reason my vertical walls are inconsistent. At first I though it was the setting but after switching out filaments my vertical walls were perfect. Not sure if it's due to inconsistency's by I just cannot get decent prints with it.
Other ESUN filaments seem fine, might just be the one roll.
With this you could start including the data from this in filament reviews! Amazing work!
Consider a rotary encoder wheel samwhiched on the filament itself to measure position in the spool rather than measuring spool angular position. This automatically accounts for the diameter of the spool growing as it takes up yarn, and removes the need for precise control of the takeup spool.
Props for keeping it open sourced 😘
Awesome video Tom, really great setup!
I see all of your readings put the average diameter of the filament at approx 1.7, rather than the 1.75mm, do you intend to do more calibration on diameter? Since your data and Prusa's data lines up so well, and as you say, Prusa will be using some top-notch laser sensors, you could potentially use their data to further calibrate the diameter measurements of your sensors. I do think a more accurate reading on the diameter would make your setup even more powerful, particularly if you do plan to use it to actively compensate for flow rate on a 3D Printer.
I have been involved with filament production for the last few months and it has been quite a learning curve! One of my key takings has been that spool consistency is also incredibly important. For example, if a filament holds a +/- 20 micron tolerance per spool but the average diameter fluctuates, the results between successive spools will make for more noticeable under/over extrusion. From this perspective, I would suggest that the average diameter is actually more important than the tolerance of the spool itself (within reason). While obviously important, I do think that tolerance is something a lot of print users unnecessarily obsess over and there are many more important factors at play when it comes to getting the best prints. A prime example of this being the 'print your own filament' videos that have cropped up, where the tolerance is likely to vary quite wildly and yet some great prints have been produced from this process (ref. CNC Kitchen's Bency with PC-ABS). Maybe a piece of printed filament is something you might even like to test with your new measurement setup.
Keep up the good work! I'm releasing my filament soon, will have to send you a spool.
Callum
Thank you so much,
. I have been wanting to do this for a while now. I think you are one of the best. Thanks and keep up the good work.
This is a very cool testing rig. I love the use of hall-effect sensors here, very clever! I haven't really had any issue personally with filament inconsistencies, but it would be interesting to compare two spools of the same filament, but from different batches. Thanks for the video tom, I really like your experiment videos! 🧡💙
This is just amazing results and a rely nice tool setup !!
Cool project, one question though . When calibrating the filament with a drill bit, wouldnt that throw your readings off a little .Since the metal drill bit would couple more magnetic flux then using a non-metallic object. Or does that not matter though since you are measuring the magnitude of change in magnetic field.
This is what I have been waiting for
only when you your own designs its possible to appreciate how well is this desgined ;] nice one
Recently I've had an issue with DevilDesign PET-G - after 2-3 1h prints, the diameter changed from ~1.71 at the beginning of the spool to 1.74. measured with a micrometer
I hope to see you test more brands (and maybe more spool from the same brand) in the future. Great idea and video.
What are the boards you hook up to the hall sensors? I assume the boards are what allows the I2C communication? Can you hook up anything to these boards or are they specific to the hall sensor?
I've had problems with several filaments so far, but the diameter was none of the causes.
I've had a blue night-glow PLA from Amolen that almost didn't glow, I had a blue semitransparent PLA that had rigid sections where it broke like glass as it pulls through the filament end sensor, I had several cheap PLAs off Amazon that were so crappily wound that they had 45 degree kinks in them or were so tightly wound and/or stored so warm that layers on the spool fused together.
So far, my best experiences were with the PLA from Anycubic, with PrimaCreator EasyPrint PLA and Janbex PLA. Basicfil is so-so, some spools were neatly wound, others were rather messy, which suggests they are reselling different sources.
This is absolutely fantastic!!!
Great solution for measuring Filament😀
Thanks for the input
Klasse Arbeit