I think one of the newer HF hotends with melting zone integrated in the heatsink like the Mosquito or Dragon with a CHT nozzle would be another interesting test. It's quite a bit more compact compared to the long Volcano block and probably has some other benefits as well.
Nope. I want to print Carbon-Fiber and Glass-Fiber reinforced fillaments, and I want to print them fast, but there's no hardened steel CHT nozzle and, probably, never will be.
You can use the 3 holes to screw in the spacer - that way you don't need the hex socket and you might be able to improve the inlet geometry to reduce drag. Also, consider polishing the bores with a smooth wire charged with a polishing paste like Brasso.
Gonna be tricky to line up the holes though. The hex cavity makes that bit a non-issue. If the spacer gets a bit stuck, the leverage of a larger 3-4mm hex key might mean the difference between extraction and a useless, potentially quite expensive heatblock. What we'd ideally have here, would maybe be a heatbreak with its hot side extended by 8.5mm. Only works for single straight bore though.
@@SteveEh That's assuming you're able to extract the heat break first without relieving the compression tension between it and the spacer. Depending on your hotend and heatbreak type, that might not realistically possible without shearing/breaking lt, with how thin walled the separation neck on a lot of heatbreaks are. Most heatbreaks do not have a nut or hex flange/collar on the hot side of the neck you can wrench on like the mosquito / dragon do. A snapped-off heatbreak stuck in there too, isn't gonna help. Nor will a hard AF snapped-off drill bit.
@@Audio_Simon I was frankly surprised Stefan didn't do that, drilling an indent after doing the small holes to avoid flats and sharp edges perpendicular to flow. Or maybe he did and I might have missed it, watched it on my phone so details get very small. Drilling an indent with the same 60° cone as at the nozzle end might be good? But making the indent spherical with a ball end mill might do well too.
One question, would sharpening the start of the 3 holes in your spacer help out with extrusion? because the CHT seems to have it to help slice the filament a little easier instead of being force melted through with brute force
I think its somewhat sharpened, just cause of the orientation when mounted. Sure, could be sharper, but the Filament doesnt just get bluntly shoved against the hex part of the spacer.
Also, the division is quite high up in the heat block, so the filament hasn't had much time to melt yet. There could be some advantage in tuning how far down the heat block the 3 holes commence.
@@b4Bub0i I don’t think it’s the hex part he’s talking about. In the CHT it has a sharpened middle which splits the filament before it gets fully melted. If you look at his DIY version there’s quite a bit more material in the middle.
also how would that all effect retractions. For that reason alone I feel more confident in something like Micro Swiss TwinClad XT coated nazzle (it has 0.08 friction coefficient vs usual nickel plating that has 0.2), may help it gain on CHT, but I didn't see any direct test out of those yet. CNC Kitchen let doooo it :D
No, the patent covers any material which conducts heat from the heatblock into the melt zone within the bore, basically the guy was able to patent any bore that isn't a straight cylindrical shaft through a heatblock. It's an insanely overreaching patent, kinda surprising he could even get a patent that general tbh
I came to say the same thing. If the patent is on melting geometries, than maybe not, but if the patent is for a high flow NOZZLE then maaybe. You could also potentially make a heater block with high flow holes in it and then it would definitely not be a nozzle.
@@xxportalxx. i would think you could fine previous art for that. it would very much surprise me if this hadn't been used before in some industrial application or other high heat transfer application. also patents are by default written to be overreaching and see what sticks. makes them harder to fight/get around
Machinist here... In order to drill the 3 holes into the brass it's much easier to start with an End Mill that can plunge into the material to create a flat spot and then use the drill. That should get you a more uniform and much easier to make extension piece!
Longtime viewer, first time commenter. Just wanted to say, I love your content, and the way you've standardized testing for filament is genius. There's not a lot of independently verified information about the performance characteristics of filament (that I know of), and it provides a great service to the 3d printing community. I also appreciate seeing you getting into machining, as a machinist by trade myself. However, some of the things you do while machining drive me bonkers lol. The most apparent one, and the one I've seen commented on before, is drilling holes. You should always center drill, or spot drill, before a drill op. Not only is this best practice, but you'll greatly extend the time between resharpening your drill bits, as it takes a lot of load off of the tip of the drill bit (the most fragile part). This is likely why you were getting such massive deflection on the hotend with the copper wires. Best of luck, and keep at it! Machining is an art, and very little things like that can effect results in ways that you wouldn't expect. Would highly recommend finding a machinist friend that you can consult with questions about fixturing and best practices!
Exactly what i was going to say! If its not long enough to bridge 8.5mm just shorten the volcano nozzle accordingly to match. Then we get best of all worlds
We need a 3D printing crossover episode where CNC Kitchen designs a nozzle and VOG uses resin printing plus investment casting to produce it. The upper bound on flow rate is determined by heater cartridge wattage, and the practical limit is determined by heat transfer (a function of contact time, surface area, and thermal conductivity). My first thought is a central channel that starts out like a Koch Snowflake and then lofts into a circle before the nozzle exit (and I would make the test nozzle out of copper to test the best case scenario).
For the 3-hole adapter: if you still have your 3-jaw chuck you can clamp the piece in it but place a small spacer on one of the jaws to create an offset of the rotational axis and drill the off-center hole pretty much standard as a concentric hole (but slower because of the imbalance). Then rotate it approximately by 120 degrees and repeat. The more professional solution would be a 4-jaw chuck with independent jaws. Edit: do it on the flat side, not on the hex side
Good solution. There is no significant imbalance with these tiny parts and brass cutting speeds. Lathe headstocks are designed to swing some crazy off center loads. I also suggested ditching the hex and milling a slot afterwards to use a flat blade screwdriver for installation. If you want to get fancy, 2 slots on the edge lets you use a fork and keeps the melt zone clean of any potential diversions.
Good one. Do this and get rid of the hex nut slot, make a tool that mates with the three holes (Like another person suggested) and you should have better performance.
Came here to say something similar... Would suggest putting the (threaded) spacer in a nut (temp loktite it in) and 3-jaw chuck the nut instead of the threads. (Obviously, doesn't do much for precision, but it'll still be better than trying to do it in a drill press.
(Other advantage of putting it in a hex nut: Makes it really easy to index. Drill a hole, rotate it by 2 faces, drill a hole, rotate by 2 faces, done. Make sure your shim(s) stay on the same jaw(s) and your holes will be parallel and evenly arranged around the center.)
Thanks for video Stefan. A couple of suggestions 1. Cut off nozzle part of CHT and use splitter as spacer for Volcano. Maybe increase cone on the nozzle input to match splitter output 2. With brass spacer there is no need to drill three holes, it's counterintuitive. Make a new spacer from volcano or standard nozzle. Drill spacer's output to a larger diameter, keep input diameter. Pressfit or just insert cross, bar, three-pointed star, spiral or whatever to the larger diameter part. Use with nozzle with increased input cone. 3. Please try to drill volcano and standard nozzles inputs to a larger diameter then pressfit spiral and straight metal strip 4. There is no need to have hex socket at all. Screw in your spacer, screw in the nozzle and align them. Then screw in your heat break and tighten it. Then you can assemble everything and/or change nozzles. Adding screw from side of heat block to secure spacer may help. Also, there are heat breaks with hex head which will help tighten, see "Mosquito heat break" 5. Please do materials vs CHT
@@KentoCommenT if you have brand new heater block with clean thread then you should be able to screw in the spacer just by hands. If thread is not clean enough you can try burn out plastic remainings and/or use tap. To screw spacer in when it is too deep you can use any conical shaped tool like small pliers, round nose pliers, tweezers, round file, maybe even toothpick
Countersink the holes on your high melting rate adapter so that the middle comes to a point like the CHT nozzle. I think the problem is that you have to melt most of the filament with that middle bridge part and that's limiting your flow rate. You want to split the filament instead so that it can melt in the smaller holes. It still had the melting rate advantage though, which is why you got less die swell I think.
No way, I was just doing the same thing! It's super cool to see some great data on this idea, and it's super interesting how little it affected the performance, given the massive improvement with the CHT. For the drilling, I've been trying to drill the holes first, then cut the angle to give the angled hole face. That way, I'm drilling on a flat surface instead of an angled one. additionally, instead of using a hex to screw it in, I'm just using a custom-made screwdriver with steel pegs that fit in the holes. That lets me use the chamfered start geometry that is on the CHT, which I think will improve the flow from what you saw. It also lets you just use m6 brass bolts, which are much easier to find. I'm going to try using your same testing style to test mine soon!
11:00 I suspect that much of the problems with the CHT nozzle high flow spacer combination is hole alignment once assembled in the heat block. Once the molten plastic exits one of the holes of the high flow type spacer, its not necessarily a straight shot into one of the three holes in the CHT nozzle. Add in the pocket from the recess for the socket drive key of the spacer and the slight pocket before the separation of the 3 holes of the CHT nozzle and and you are getting small turbulent / flow restriction pocket area at the interface between the spacer and the nozzle. To possible solve the alignment and pocket issue, why not take a 3mm volcano nozzle (or a 1.75 and drill) and ream it to whatever bore size necessary (if necessary) then take a piece of brass bar stock and turn it to match the bore size (plus maybe .0 to .02mm or so for a light press fit) and drill your three 1.2mm holes in that slug thus giving you the 3 hole high flow design of the CHT nozzle but in the Volcano length with no spacer or misalignment and mid stream pocket problems associated with the "high flow spacer" and CHT nozzle. You could make the insert slug slightly longer than what the depth of the bore is of the nozzle thus allowing you to mill it back to be perfectly flush with the end of the nozzle where it seats against the heat break.
@Resto Ron Yep, even as little as a 32nd (0.8mm) lip from mismatched ports between the head(s) intake and/or exhaust can create enough turbulence in airflow that power and efficiency is lost. A lot of people think, along the lines of area loss from the mismatch (which is often miniscule) but never consider that its not the area loss that is a problem but rather the turbulence created by the mismatch and turbulence kills airflow (or any fluid flow).
Thank you for actually progressing the art instead of endless reviews of mediocre products as nearly all other 3dp 'creators' seem to be stuck on. Seriously, Drinks on me if we ever cross paths. Edit: Nitram included!
A stub length drill setup as short as possible would have also had a much better chance to drill straight. Or... you know... just drill it from the flat side.
I just made my own last night, i found simply jamming a Torx bit gives you plenty of grip to snug it up then turning the throat about 1/8-1/4 holds it on more than tight enough. I used copper anti seize on the adaptor and nozzle, left the throat dry as to prevent heat transfer. I'm printing with a proper hardened nozzle (0.5mm), hasn't even got a scratch from me wrenching on it with pliers and the adaptor is copper (not brass) with a titanium throat. I was amazed how consistent the heat is. I printed ABS at 260c/250mms outer perimeters/infill and the parts show a slight glaze/shinny surface consistently through out. Then moving upto 400mms shows it matte on some parts of the peace's but no under extrusion at all, this is with a standard extruder 😳
Hi Stefan, can you try using the DIY high flow modification on a volcano spacer? It should be much easier to solder in some wires than to drill three tiny holes inside of a cone.
Just a little idea that came to my mind yesterday : replace the wire in the diy high-flow hotend by a thin strip => you would get core heating and laminar flow in the same time. About the machining process, I though of this procedure : 1)drill a .4-1mm hole in the threads of a v6 nozzle 2)by using a jewellery saw, or one of the tipe with really thin blades that are straightened by the rest of the saw that pull on the ends of the blade (with a wide U shape), findable in hardware stores here in france. You pull the blade through the holes, thight it in the saw and extens the holes into grooves, 3) pull a thin strip of thermally conductive metal (copper, brass, nickel seems easily sourceable as it's used in Li-ion battery packs, aluminium should be common in cakes packaging or cans, just don't forget to get yourself special solder for aluminium) 4) solder the strip in place 5) cut off the excess material 6) thread back the nozzle
Several people have suggested using a centre-cutting endmill to start the three holes, but another way is to push a piece of hex brass into the hex pocket, flatten off the end flush with the spacer surface, centre punch and drill. The same technique can be used to drill overlapping holes by filling each hole with brass rod after it's drilled, before drilling the next.
I tested a simple adapter with a straight 2.5mm bore and a cht a couple weeks ago on my Volcano dragon and got basically the same results. Finally enough flow to break into the 5 minute benchy territory.
For a remake of the High-Flow-Spacer, you could skip the initial counterbore and instead counterbore the individual paths on both ends to create the "wedges". This would also greatly simplify the process of actually drilling the extrusion paths, as you wouldn't be fighting against a sloped surface.
I think the "one hole" adapter is much better because you are pre-heating the filament such that when it gets to the CHT 3-hole section it is soft enough such that it doesn't fight the feeder so much. PRE HEAT FOR THE WIN!
@@celeron55 It could also be good for adding a randomized irregular texture to something, like a sort of "popcorn ceiling" effect. And the spinning nozzles might be good if you just want to make a mess~
Its probably been suggested already, but im the future you could probably make a guide for you drill bit. Dill your 3 hols through a material that is easier to place them and use it to guide your bit to its final location. The center drill is absolutely a must as well. Good to see
I'm sure others have said this already, but I would forget the hex hole, and just get a threaded brass rod at the proper length. 1. Using a drill press or milling machine and a vertical chuck, drill the three holes, rotating the chuck 120 degrees between each hole (I would advise putting the holes as close to the center as reasonable) 2. Countersink both ends of each hole so that in the end the holes meet at a point in the center, just like on the CHT hot end 3. Either fashion a special forked tool that lets you screw the spacer into the heater block by putting the tines into the three holes OR Cut a shallow line across one end of the spacer so that a flathead screwdriver can drive the spacer into the heater block. I expect this should help reduce the resistance to flow and may also help to reduce turbulent flow exiting the spacer.
I commented thsi last time and I'll say it again: twist drills need a flat spot to drill into or they'll wander. Mill a flat spot to start with with an endmill or countersink and then drill.
As always, fascinating and useful information! I recently did a big vase mode print with that weird distortion, which I'd never experienced before. My speeds and feed rate weren't any higher than I normally use, but without retractions and moves, I think it wasn't able to properly melt the filament! This video solved one of the baffling 3D print issues I've run into over the last few years!
For doing tiny drilling like that, you could print a sleeve for the drill bit that is 10mm from the end of the bit and is long enough to butt against the chuck of the drill press. That should stiffen the drill bit enough to allow it to act like a short jobber bit then you can remove it once you are able to go deeper on the drilling. Also, when you make tiny punches like the one in the video, you can use a trick that TIG welders use to sharpen their tungsten rods. Put the thing you want to put a point on into your cordless drill and use that to spin the metal while you take it to a grinder. You get more control and a nicer cone shape on it, plus you wont burn your fingers from the heat creep.
Tests are good, but I think you have to test how it affects retractions, most people made reviews and showed how well CHT pushes filament, but I have gut feeling that due to complex shape of the channel we might have issues with retractions. Would be nice topic for the video.
1) Tap threads inside nozzle. 2) Tap thread (O.D.) a 4mm brass rod. 3) Grind (or mill) three channels into side of rod. 4) Cut rod to length. 5) Make a three pin tool to screw your three channel rod into nozzle. This way all the work is done outside of the nozzle.
Great job as always! One simple idea for the adapter... can't you just use a straight tube spacer, like OD=5, ID=2? The lack of thread engagement would translate to slightly less thermal conduction, but as long as it's copper it shouldn't be a deal breaker, and it would be much easier to make & install.
I was thinking along the same lines. Could you modify the heat block to not need the spacer to be threaded. Or have a threaded section with a large bore that the smaller space slides through.
@@CNCKitchen want i mean is the tool at your disposal is a reseller selling the actual parts. No sense making something yourself with thousandths worth of equipment if you can just buy it for couple of hours wage for real. Not to undermine your work of course but you know.
Really cool to see how you worked around the nozzle patent by creating a spacer to speed up the melting, although there is one thing you lose by using the spacer - the ability to do a 'proper' cold pull, I'd hate to have a clogged nozzle with that setup.
When drilling the 3 holes a simple way to minimize drill walk is to fill the void with a material that can be easily removed afterwards. Flatten the end and you have a nice easy to reach surface to start on.
Can't you use an end mill to flatten the inside of the hex bore? That would make drilling easier. Even a cheap AliExpress one in your drill press should work for brass. I also suggest some light filing to sharpen the edges of your extension like the CHT nozzle.
@@CNCKitchen it might be a bit tricky bought you could also scrap the hex and make a custom tool that uses the 3 holes instead to screw it in. (3 busted drill bits of the same size in a small 3D printed part. )
11:23 I think that you are correct when you said that you add additional stress by adding turns, but you may also have some unaligned holes by the junction of the the two thus creating more backpressure.
The CHT opening acts as a blade. The blade is needed at the beginning of the splitting of the not thru-melted filament. Maybe you should cut the nozzle of 2 more CHT nozzels and make them an extention
Just wanted to throw in my 2c. Your cross sectional area of the holes just exceeds that of the 2mm bore, however with three smaller bores you get an increase in total internal wall surface area contacting the melted filament, thus increasing the flow friction. This may have some bearing/impact on extrusion behaviour. Given the two examples with similar performance - CHT nozzle with standard spacer, or 3 hole spacer with standard nozzle, you're getting approximately the same length worth/same increase in surface area, and therefore flow friction. But you're essentially doubling it by using the CHT nozzle with the 3 hole spacer. That, in conjunction with the other technical hurdles as described by other commenters, could be a contributing factor in the reduction of overall extrusion performance with this combination. I see Bondtech now have a CHT volcano nozzle. Be interesting to see how that performs in comparison with what you've already tested.
Wirklich mal wieder eine saubere Studie! Kleine Anmerkung: Die Dimensionierung der drei Bohrungen sollte nicht nach dem Kontinuitäts-Prinzip sondern nach Hagen-Poiseuille (Reibungsdruckabfall im Rohr) erfolgen. Dann kommt man in Näherung (dV/dt=konst.) zu r2^4/(3*r1)^4 = konst. und damit zu knapp 1,5mm je Bohrung. Damit sollte die Extrusionskraft in etwas konstant bleiben können.
Better option IMO is the high-flow spacer with a standard nozzle, because that would allow you to use hardened nozzles, including E3D's upcoming one with a diamond-like coating (DLC). The CHT nozzles are only nickel-plated brass.
@@AmaroqStarwind i'd say the dlc is probably a better option as, because of the ruby, it is hard to get it in the same preferrable 60° angle for optimal flow characteristics like E3D's nozzles use, also Ruby's are expensive
@@BH4x0r Synthetic ruby and synthetic sapphire are both options, just like synthetic diamond-like carbon. Also keep in mind that the entire diamond market is built on a scam.
Yesss! As a volcano user, the CHT was great but not so in converting all my systems away from volcano, now I'll just patiently wait for someone to make proper extension bores and can upgrade my volcano's into something even better!
It came to my mind with previous video on the subject. Drilling in nozzle's side might be tricky for someone without drillpress. I figured out that using flat piece of copper (hammered copper wire) and just sawing nothes in nozzle's top will be much easier. Would still need soldering though. Going this way would also lower the resistance as those copper strips in + pattern would work like slim knifes slicing through the filament on the entry. This could work for such extender/adapter as well with longer slits in its body.
Another superb presentation with clarity and technical excellence. I do have a Volcano head with a 0.8mm nozzle. Your investigation shows me a direction to go to improve print speed: A CHT nozzle and a straight through extension for its ease of manufacturing. Vielen Dank.
I noticed you screwed the spacer in from the nozzle end, which results in a cavity where the recess for the hex socket is. Wouldnt it be better to screw it in from the top of the block to remove the cavity? I'd have thought that cavity would have an effect on retraction, backpressure etc.
@@CNCKitchen in your testing yes it makes sense to do it from the bottom because of the repeated testing. But for someone doing it once, would be better done from the top i'd assume.
Have you considered using copper slip/copper anti seize. It's used on the back of brake pads and on the studs /nuts on an exhaust manifold often so it's very hear resistant but also due to it being copper has very high thermal conductivity so should be perfect anti seize for this application.
I'd suggest to use solder (or even printing filament) to ease all the fancy drilling. First, fill the hex to the borders. Then drill offset hole (to make some off-center jig for it also would be a good idea). starting from flat surface, it wil be much easier. Fill freshly drilled hole with more melt. Repeat for second and third holes. Also, by this method you actually can drill overlapping holes, it should be good for performance, I think. Finally, heat up the spacer to remove all temporary material.
If I was going to modify the spacer, I would tweak your copper wire idea. I'd use a redundant heat block, and make a drill guide from it. I would tap any drilled hole in the spacer, and insert a grub screw, whose length was just shy of the diameter of the unthreaded part of the spacer. Once inserted into the heat block, the grub screw will be constrained. The threads of the grub screw will increase the surface area, and in theory, help melt the filament better than plain copper wire.
I can successfully overwhelm every hotend I own using nothing but the trash can model in vase mode with a high enough print speed and layer width. I also increase the print size so it fills the build plate.
love the work here. have you tried making a jig from an allen tool? one angled hole in it as a guide. drops in, drill, droop in clocked 2 sides, and a third time.
Really appreciate your dedication! An end mill is much more rigid than a drill bit - using an end mill (or for precision, end mill then reamer) to make your 1.2mm holes might be easier in the future.
I'm really impressed your home made high flow spacer worked so well. I thought the filament would impact the middle of the spacer and cause all sorts of issues. You mentioned this may be the cause of the abrupt failure at higher speeds. I'd be very interested to see this same spacer but with the entry to the 3 holes bored out more so the middle meets at a nice sharp point like the CHT nozzle. Great video and impressive work to manufacture your test spacers.
Shorten the drill bit to create the pilot hole to avoid deflection. It can be easily done by either buying shorter drill bits or by placing the longer drill bit deeper into the chuck..
Have you considered cutting a groove across the top of a standard nozzle and just soldering the copper wire up there? You could even bend it in a u shape to go down into the chamber. Maybe pound it flat to make it more like a blade.
I would try cutting the CHT nozzle as the spacer, and cut a volcano nozzle down to fit. This would provide the precision machined division to quickly melt the filament, then combine again into the standard nozzle. this might reduce the pressure enough to get a bit more performance before the extruder starts to slip.
Well, seems like the optimal solution would be to place the heating element into a needle and and build it like an airbrush nozzle. Also having a longer straight end to get more laminar flow inside the nozzle. We could modify a cartdrige soldering iron.
You should try to make Volcano nozzle with perpendicular copper wires. Then you could make cavity closer to nozzle output and "CHT-like" system in top part to make similar combination to standard V6 nozzle + CHT adapter (which IMO performed best).
Great content as always, really makes you think deeper about how it all works inside. My guess is that first having some significant straight bore to get the material soft enough to got into the smaller channels, then the smaller channels to make sure you really get a consistent temp profile across the flow field, and then a fairly long and gradually tapering bore all the way to the nozzle, so it can settle into a nice Poiseuille flow, would be ideal. Rather than the center punching, I was thinking it should be helpful to overlay a piece of flat metal when drilling your holes, so your drill bit is maximially clamped near the relevant spot.
I just improved my volcano hotend by moving the temperature sensor from it's original bit more far from the heating element. I just drilled an extra hole for the sensor. Originally it was positioned between the heater element and nozzle which I don't find to be optimal.
Next time you drill something like that, try flattening it off and center punching the flat surface instead of messing with the pocket. You can fill the pocket with solder, part it right off on the lathe or even try filling it with epoxy resin so that you can drill straight through the resin and into the brass. Then you can remove the filler with heat and get your hex back. The simplest solution IMO - machine a flat face on ordinary rod, drill the bores and then cut a slot afterwards so you can use a flat blade screwdriver to install it. Great work on your testing, I suspect coming out of the 3 bores into a cavity and then re-entering the 3 bores of the CHT is the reason that test worked poorly.
Did he ever show how he lined up the three holes when the CHT and HF adapter were installed together? I think that even a slight misalignment of the holes would cause an increase in flow resistance.
Really loving the CHT series! Keep it up! Absolutely crazy effort on this, I can only imagine the frustration! Very interesting to see how nice the CHT is on its designed setup! Very interesting to see how all this pans out! I hope Bondtech does the CHT in hardened but I have a feeling that wont last long! Thanks again for the great video!
Brass M6 all-thread might be an more available option for stock material. A thin steel nail makes a great center punch and I rather hone a starting step onto a small drill bit to keep it centered. Brass hardens from work forming, simply punch a hex bit in and then tread thru a M6 cutter. Then Countersink the holes to finish...
How about turning a CHT nozzle into a spacer? There should be enough length in a V6 nozzle - you just need to part off the tip and turn the hex into an M6 thread. There will be a gap in the threads between the original thread and the thread that used to be hex, but it should seal between the sections OK
for improved manufacturing of the 3-hole spacer, punch and drill the holes from the flat side before drilling the indent, that way you're drilling on a flat surface instead of the faceted hex. and drilling the indent shouldn't be affected because the holes are symetrilac and therefor cancel eachothers effect on the drilling of the indent.
If you had a rotary broach you could make your own adapter from brass stock without using grub screws. drilling the three holes would be way easier using a four jaw chuck to drill off center before center drilling and then broaching the hex. Rotary broaches are kinda pricey but once you realize all you can do with them they don't seem so bad.
Could you make spacer from CHT nozzle itself ? Just cut off front part of CHT nozzle. Looks like sharpness of space between three nozzles where filament enters is important. Using CHT nozzle as spacer will make spacer perfect
Regarding the DIY manufacturing: Drilling the hole could be easier using a milling end. Also, if you are not shy grinding the drillbit, one could shorten it, so it can't deform as severly, as you showed on video.
You should use a center cutting end mill, when trying to drill the 3 holes. You won't get any deflection. But only to get them started then change to a normal drill.
Good job Stefan! I'? Great fan of yours videos. You make very good analysis, and lots of data which I got from your videos I use in my printing. In only one year I achieved lot of progress, from noob to expert and you have big contribution in this process.
Considering your machining time and buying the grub screws, drill press, mini lathe, drill bits, maybe it would be better to just buy the $20USD CHT nozzle standard bore spacer. Thanks Stephan for showing us the way.
Your quest for faster printing is a good demonstration that all 3D printer owners would dearly love, though not just faster, but injection moulded like results. Of cause that's never going to happen with layer-by-layer additive methods :(
Great video as always! Would be very interesting to test some high flow hotends like mosquito magnum and drogon HF with and without the cht nozzle. These combinations could give extreme flow rates
One massively underrated bonus of this is the more permanent seal between heatbreake and hotend. Nothing about 3D printing has annoyed me as much as the lousy way heatbreakes are supposed to form a seal by pressing on the hotend.
Nice video Stefan, I got to similar conclusions. and currently run with 0.4 CHT and a single 2.0mm hole in my magnum equipped #VolcoMosq.. the highflow spacer + CHT ended up with too high forces, so the polymer stiffness and the extruder capability to feed the filament was the limiting factor for the most..
have you tried soldering blades into a vulcano hotend? got quite good results by this. Had to slot the nozzle and then pushed a blade into it. used some high temp solder afterwards. but also want to try a version without solder and slot in the future. neverless the resistence of the blade was way less then the drilled holes which seems to work better for me.
Have you considered brazing the copper wire into a plated copper volcano nozzle to allow for higher temperatures? Also, a copper nozzle has better heat transfer than brass, so it should have better flow and heat transfer to the wire. Although, you have to remove the nickel plating with a wire brush or some abrasive fleece.
![Eminem - Fuel (feat. JID) [Official Lyric Video]](http://i.ytimg.com/vi/t5H_CewqpKA/mqdefault.jpg)
Volcano is Dead, Long Live Volcano!?
:O
I think one of the newer HF hotends with melting zone integrated in the heatsink like the Mosquito or Dragon with a CHT nozzle would be another interesting test.
It's quite a bit more compact compared to the long Volcano block and probably has some other benefits as well.
Nope. I want to print Carbon-Fiber and Glass-Fiber reinforced fillaments, and I want to print them fast, but there's no hardened steel CHT nozzle and, probably, never will be.
What about 3 extruders feeding 3 filaments into one nozzle like the colormix nozzle but for speed not colormixing?
I have an idea you could convert a CHT nozzle into the spacer (remove the hex and tip and cut treads) and then use a shortened volcano nozzle.
You can use the 3 holes to screw in the spacer - that way you don't need the hex socket and you might be able to improve the inlet geometry to reduce drag. Also, consider polishing the bores with a smooth wire charged with a polishing paste like Brasso.
Gonna be tricky to line up the holes though. The hex cavity makes that bit a non-issue. If the spacer gets a bit stuck, the leverage of a larger 3-4mm hex key might mean the difference between extraction and a useless, potentially quite expensive heatblock.
What we'd ideally have here, would maybe be a heatbreak with its hot side extended by 8.5mm. Only works for single straight bore though.
@@pr0xZen If it did happen to jam in the block, a simple twist drill bit would grab it enough to push it thru.
@@SteveEh That's assuming you're able to extract the heat break first without relieving the compression tension between it and the spacer. Depending on your hotend and heatbreak type, that might not realistically possible without shearing/breaking lt, with how thin walled the separation neck on a lot of heatbreaks are. Most heatbreaks do not have a nut or hex flange/collar on the hot side of the neck you can wrench on like the mosquito / dragon do. A snapped-off heatbreak stuck in there too, isn't gonna help. Nor will a hard AF snapped-off drill bit.
I just wrote this, lol. You could add a detent after doing the holes to aid flow. Point is to do the drilling on a flat stock.
@@Audio_Simon I was frankly surprised Stefan didn't do that, drilling an indent after doing the small holes to avoid flats and sharp edges perpendicular to flow. Or maybe he did and I might have missed it, watched it on my phone so details get very small.
Drilling an indent with the same 60° cone as at the nozzle end might be good? But making the indent spherical with a ball end mill might do well too.
One question, would sharpening the start of the 3 holes in your spacer help out with extrusion? because the CHT seems to have it to help slice the filament a little easier instead of being force melted through with brute force
I think its somewhat sharpened, just cause of the orientation when mounted. Sure, could be sharper, but the Filament doesnt just get bluntly shoved against the hex part of the spacer.
Also, the division is quite high up in the heat block, so the filament hasn't had much time to melt yet. There could be some advantage in tuning how far down the heat block the 3 holes commence.
@@b4Bub0i I don’t think it’s the hex part he’s talking about. In the CHT it has a sharpened middle which splits the filament before it gets fully melted. If you look at his DIY version there’s quite a bit more material in the middle.
I think adding a chamfer would decrease the flow resistance.
also how would that all effect retractions. For that reason alone I feel more confident in something like Micro Swiss TwinClad XT coated nazzle (it has 0.08 friction coefficient vs usual nickel plating that has 0.2), may help it gain on CHT, but I didn't see any direct test out of those yet. CNC Kitchen let doooo it :D
I'm wondering, does this "high flow spacer" actually completely circumvent the CHT nozzle patent, considering it's not a _nozzle?_
This is big brain
No, the patent covers any material which conducts heat from the heatblock into the melt zone within the bore, basically the guy was able to patent any bore that isn't a straight cylindrical shaft through a heatblock. It's an insanely overreaching patent, kinda surprising he could even get a patent that general tbh
@@xxportalxx. Unfortunate. Sadly this is what happens when the people looking over patent applications aren’t well versed in the field.
I came to say the same thing. If the patent is on melting geometries, than maybe not, but if the patent is for a high flow NOZZLE then maaybe.
You could also potentially make a heater block with high flow holes in it and then it would definitely not be a nozzle.
@@xxportalxx. i would think you could fine previous art for that. it would very much surprise me if this hadn't been used before in some industrial application or other high heat transfer application. also patents are by default written to be overreaching and see what sticks. makes them harder to fight/get around
Machinist here... In order to drill the 3 holes into the brass it's much easier to start with an End Mill that can plunge into the material to create a flat spot and then use the drill. That should get you a more uniform and much easier to make extension piece!
Longtime viewer, first time commenter. Just wanted to say, I love your content, and the way you've standardized testing for filament is genius. There's not a lot of independently verified information about the performance characteristics of filament (that I know of), and it provides a great service to the 3d printing community.
I also appreciate seeing you getting into machining, as a machinist by trade myself. However, some of the things you do while machining drive me bonkers lol. The most apparent one, and the one I've seen commented on before, is drilling holes. You should always center drill, or spot drill, before a drill op. Not only is this best practice, but you'll greatly extend the time between resharpening your drill bits, as it takes a lot of load off of the tip of the drill bit (the most fragile part). This is likely why you were getting such massive deflection on the hotend with the copper wires.
Best of luck, and keep at it! Machining is an art, and very little things like that can effect results in ways that you wouldn't expect. Would highly recommend finding a machinist friend that you can consult with questions about fixturing and best practices!
You could try to cut a CHT and use it as a spacer, which might end up having a higher performance than the DIY HF Spacer
Exactly what i was going to say! If its not long enough to bridge 8.5mm just shorten the volcano nozzle accordingly to match. Then we get best of all worlds
@@vericksworkshop5007 or cut 2 cht nozzles
that works until you need to disassemble
@@julesadventures9174 with that in mind, he could cut a slot for a screwdriver using a handsaw. Might not be perfect but if it works, it works
@@lucasvp2005 Or Just make special wrench or screw driver that could use those 3 holes for grabbing.
We need a 3D printing crossover episode where CNC Kitchen designs a nozzle and VOG uses resin printing plus investment casting to produce it. The upper bound on flow rate is determined by heater cartridge wattage, and the practical limit is determined by heat transfer (a function of contact time, surface area, and thermal conductivity). My first thought is a central channel that starts out like a Koch Snowflake and then lofts into a circle before the nozzle exit (and I would make the test nozzle out of copper to test the best case scenario).
For the 3-hole adapter: if you still have your 3-jaw chuck you can clamp the piece in it but place a small spacer on one of the jaws to create an offset of the rotational axis and drill the off-center hole pretty much standard as a concentric hole (but slower because of the imbalance). Then rotate it approximately by 120 degrees and repeat. The more professional solution would be a 4-jaw chuck with independent jaws.
Edit: do it on the flat side, not on the hex side
Good solution. There is no significant imbalance with these tiny parts and brass cutting speeds. Lathe headstocks are designed to swing some crazy off center loads. I also suggested ditching the hex and milling a slot afterwards to use a flat blade screwdriver for installation. If you want to get fancy, 2 slots on the edge lets you use a fork and keeps the melt zone clean of any potential diversions.
Good one. Do this and get rid of the hex nut slot, make a tool that mates with the three holes (Like another person suggested) and you should have better performance.
Came here to say something similar... Would suggest putting the (threaded) spacer in a nut (temp loktite it in) and 3-jaw chuck the nut instead of the threads. (Obviously, doesn't do much for precision, but it'll still be better than trying to do it in a drill press.
(Other advantage of putting it in a hex nut: Makes it really easy to index. Drill a hole, rotate it by 2 faces, drill a hole, rotate by 2 faces, done. Make sure your shim(s) stay on the same jaw(s) and your holes will be parallel and evenly arranged around the center.)
this is how i thought he was going to do it at first
Thanks for video Stefan. A couple of suggestions
1. Cut off nozzle part of CHT and use splitter as spacer for Volcano. Maybe increase cone on the nozzle input to match splitter output
2. With brass spacer there is no need to drill three holes, it's counterintuitive. Make a new spacer from volcano or standard nozzle. Drill spacer's output to a larger diameter, keep input diameter. Pressfit or just insert cross, bar, three-pointed star, spiral or whatever to the larger diameter part. Use with nozzle with increased input cone.
3. Please try to drill volcano and standard nozzles inputs to a larger diameter then pressfit spiral and straight metal strip
4. There is no need to have hex socket at all. Screw in your spacer, screw in the nozzle and align them. Then screw in your heat break and tighten it. Then you can assemble everything and/or change nozzles. Adding screw from side of heat block to secure spacer may help. Also, there are heat breaks with hex head which will help tighten, see "Mosquito heat break"
5. Please do materials vs CHT
Question for 4: How do you do the first step?
@@KentoCommenT if you have brand new heater block with clean thread then you should be able to screw in the spacer just by hands. If thread is not clean enough you can try burn out plastic remainings and/or use tap. To screw spacer in when it is too deep you can use any conical shaped tool like small pliers, round nose pliers, tweezers, round file, maybe even toothpick
Countersink the holes on your high melting rate adapter so that the middle comes to a point like the CHT nozzle. I think the problem is that you have to melt most of the filament with that middle bridge part and that's limiting your flow rate. You want to split the filament instead so that it can melt in the smaller holes.
It still had the melting rate advantage though, which is why you got less die swell I think.
No way, I was just doing the same thing! It's super cool to see some great data on this idea, and it's super interesting how little it affected the performance, given the massive improvement with the CHT. For the drilling, I've been trying to drill the holes first, then cut the angle to give the angled hole face. That way, I'm drilling on a flat surface instead of an angled one. additionally, instead of using a hex to screw it in, I'm just using a custom-made screwdriver with steel pegs that fit in the holes. That lets me use the chamfered start geometry that is on the CHT, which I think will improve the flow from what you saw. It also lets you just use m6 brass bolts, which are much easier to find. I'm going to try using your same testing style to test mine soon!
have you shared some pictures of the driver and the spacer somewhere ? would love to see it ! :D
11:00 I suspect that much of the problems with the CHT nozzle high flow spacer combination is hole alignment once assembled in the heat block. Once the molten plastic exits one of the holes of the high flow type spacer, its not necessarily a straight shot into one of the three holes in the CHT nozzle. Add in the pocket from the recess for the socket drive key of the spacer and the slight pocket before the separation of the 3 holes of the CHT nozzle and and you are getting small turbulent / flow restriction pocket area at the interface between the spacer and the nozzle.
To possible solve the alignment and pocket issue, why not take a 3mm volcano nozzle (or a 1.75 and drill) and ream it to whatever bore size necessary (if necessary) then take a piece of brass bar stock and turn it to match the bore size (plus maybe .0 to .02mm or so for a light press fit) and drill your three 1.2mm holes in that slug thus giving you the 3 hole high flow design of the CHT nozzle but in the Volcano length with no spacer or misalignment and mid stream pocket problems associated with the "high flow spacer" and CHT nozzle. You could make the insert slug slightly longer than what the depth of the bore is of the nozzle thus allowing you to mill it back to be perfectly flush with the end of the nozzle where it seats against the heat break.
@Resto Ron Yep, even as little as a 32nd (0.8mm) lip from mismatched ports between the head(s) intake and/or exhaust can create enough turbulence in airflow that power and efficiency is lost.
A lot of people think, along the lines of area loss from the mismatch (which is often miniscule) but never consider that its not the area loss that is a problem but rather the turbulence created by the mismatch and turbulence kills airflow (or any fluid flow).
Thank you for actually progressing the art instead of endless reviews of mediocre products as nearly all other 3dp 'creators' seem to be stuck on.
Seriously, Drinks on me if we ever cross paths.
Edit: Nitram included!
Life-time-all-you-can-eat Leberkas for Nitram and Stefan 😍
I have to visit you both next year
@@Nitram_3d Oh yeah do that, I’ll make some leberkas and provide some cool Bavarian beers ☺️
When needing to drill a hole on an angled surface, first spot face the start of the hole with a flat bottom endmill near the same size as the drill.
Exactly our just use the square end mill for the initial 4mm depending on the cutting flute length.
Or use a rigid setup and a spot drill.
A stub length drill setup as short as possible would have also had a much better chance to drill straight. Or... you know... just drill it from the flat side.
I just made my own last night, i found simply jamming a Torx bit gives you plenty of grip to snug it up then turning the throat about 1/8-1/4 holds it on more than tight enough. I used copper anti seize on the adaptor and nozzle, left the throat dry as to prevent heat transfer.
I'm printing with a proper hardened nozzle (0.5mm), hasn't even got a scratch from me wrenching on it with pliers and the adaptor is copper (not brass) with a titanium throat. I was amazed how consistent the heat is. I printed ABS at 260c/250mms outer perimeters/infill and the parts show a slight glaze/shinny surface consistently through out. Then moving upto 400mms shows it matte on some parts of the peace's but no under extrusion at all, this is with a standard extruder 😳
Hi Stefan, can you try using the DIY high flow modification on a volcano spacer?
It should be much easier to solder in some wires than to drill three tiny holes inside of a cone.
Just a little idea that came to my mind yesterday :
replace the wire in the diy high-flow hotend by a thin strip => you would get core heating and laminar flow in the same time.
About the machining process, I though of this procedure :
1)drill a .4-1mm hole in the threads of a v6 nozzle
2)by using a jewellery saw, or one of the tipe with really thin blades that are straightened by the rest of the saw that pull on the ends of the blade (with a wide U shape), findable in hardware stores here in france. You pull the blade through the holes, thight it in the saw and extens the holes into grooves,
3) pull a thin strip of thermally conductive metal (copper, brass, nickel seems easily sourceable as it's used in Li-ion battery packs, aluminium should be common in cakes packaging or cans, just don't forget to get yourself special solder for aluminium)
4) solder the strip in place
5) cut off the excess material
6) thread back the nozzle
Several people have suggested using a centre-cutting endmill to start the three holes, but another way is to push a piece of hex brass into the hex pocket, flatten off the end flush with the spacer surface, centre punch and drill. The same technique can be used to drill overlapping holes by filling each hole with brass rod after it's drilled, before drilling the next.
I tested a simple adapter with a straight 2.5mm bore and a cht a couple weeks ago on my Volcano dragon and got basically the same results.
Finally enough flow to break into the 5 minute benchy territory.
For a remake of the High-Flow-Spacer, you could skip the initial counterbore and instead counterbore the individual paths on both ends to create the "wedges". This would also greatly simplify the process of actually drilling the extrusion paths, as you wouldn't be fighting against a sloped surface.
That music stinger at 0:31 made me extrude the brown filament!
I think the "one hole" adapter is much better because you are pre-heating the filament such that when it gets to the CHT 3-hole section it is soft enough such that it doesn't fight the feeder so much. PRE HEAT FOR THE WIN!
A couple of fun nozzle ideas, for tool-changing print heads:
- Shotgun nozzle: Sprays filament in a spread-out pattern
- Spinning (angled) nozzle
A shotgun nozzle could work for extremely fast infill printing
@@celeron55 It could also be good for adding a randomized irregular texture to something, like a sort of "popcorn ceiling" effect.
And the spinning nozzles might be good if you just want to make a mess~
Its probably been suggested already, but im the future you could probably make a guide for you drill bit. Dill your 3 hols through a material that is easier to place them and use it to guide your bit to its final location. The center drill is absolutely a must as well. Good to see
I love how precise and meticulous this channel is
I'm sure others have said this already, but I would forget the hex hole, and just get a threaded brass rod at the proper length.
1. Using a drill press or milling machine and a vertical chuck, drill the three holes, rotating the chuck 120 degrees between each hole (I would advise putting the holes as close to the center as reasonable)
2. Countersink both ends of each hole so that in the end the holes meet at a point in the center, just like on the CHT hot end
3. Either fashion a special forked tool that lets you screw the spacer into the heater block by putting the tines into the three holes
OR
Cut a shallow line across one end of the spacer so that a flathead screwdriver can drive the spacer into the heater block.
I expect this should help reduce the resistance to flow and may also help to reduce turbulent flow exiting the spacer.
I commented thsi last time and I'll say it again: twist drills need a flat spot to drill into or they'll wander. Mill a flat spot to start with with an endmill or countersink and then drill.
As always, fascinating and useful information! I recently did a big vase mode print with that weird distortion, which I'd never experienced before. My speeds and feed rate weren't any higher than I normally use, but without retractions and moves, I think it wasn't able to properly melt the filament! This video solved one of the baffling 3D print issues I've run into over the last few years!
For doing tiny drilling like that, you could print a sleeve for the drill bit that is 10mm from the end of the bit and is long enough to butt against the chuck of the drill press. That should stiffen the drill bit enough to allow it to act like a short jobber bit then you can remove it once you are able to go deeper on the drilling. Also, when you make tiny punches like the one in the video, you can use a trick that TIG welders use to sharpen their tungsten rods. Put the thing you want to put a point on into your cordless drill and use that to spin the metal while you take it to a grinder. You get more control and a nicer cone shape on it, plus you wont burn your fingers from the heat creep.
Tests are good, but I think you have to test how it affects retractions, most people made reviews and showed how well CHT pushes filament, but I have gut feeling that due to complex shape of the channel we might have issues with retractions. Would be nice topic for the video.
Mhm or it could be better due to how the pressure is distributed. There's really no way to know before testing!
I love your work!
thanks for all the uploads and helping me with my 3d printing adventures!
Thanks! Happy to hear that.
1) Tap threads inside nozzle. 2) Tap thread (O.D.) a 4mm brass rod. 3) Grind (or mill) three channels into side of rod. 4) Cut rod to length. 5) Make a three pin tool to screw your three channel rod into nozzle. This way all the work is done outside of the nozzle.
Great job as always! One simple idea for the adapter... can't you just use a straight tube spacer, like OD=5, ID=2? The lack of thread engagement would translate to slightly less thermal conduction, but as long as it's copper it shouldn't be a deal breaker, and it would be much easier to make & install.
I was thinking along the same lines. Could you modify the heat block to not need the spacer to be threaded. Or have a threaded section with a large bore that the smaller space slides through.
As an actual real proper CNC machinist i cry blood every time I see a video like this
Totally understand that but I need to use the tools I have at my disposal.
@@CNCKitchen want i mean is the tool at your disposal is a reseller selling the actual parts. No sense making something yourself with thousandths worth of equipment if you can just buy it for couple of hours wage for real. Not to undermine your work of course but you know.
Really cool to see how you worked around the nozzle patent by creating a spacer to speed up the melting, although there is one thing you lose by using the spacer - the ability to do a 'proper' cold pull, I'd hate to have a clogged nozzle with that setup.
that actually is a fair point!
IF you even were to be able to perform a cold pull it would not be without damage....
When drilling the 3 holes a simple way to minimize drill walk is to fill the void with a material that can be easily removed afterwards. Flatten the end and you have a nice easy to reach surface to start on.
Can't you use an end mill to flatten the inside of the hex bore? That would make drilling easier. Even a cheap AliExpress one in your drill press should work for brass.
I also suggest some light filing to sharpen the edges of your extension like the CHT nozzle.
Or just drill the 3 holes from the flat size and add that small indent later.
I tried that but using an endmill on a drill press that's super rigid mostly just screws up the hex.
@@CNCKitchen it might be a bit tricky bought you could also scrap the hex and make a custom tool that uses the 3 holes instead to screw it in. (3 busted drill bits of the same size in a small 3D printed part. )
11:23 I think that you are correct when you said that you add additional stress by adding turns, but you may also have some unaligned holes by the junction of the the two thus creating more backpressure.
My thoughts exactly. It needs to be lined up correctly, possibly even keyed.
The CHT opening acts as a blade. The blade is needed at the beginning of the splitting of the not thru-melted filament. Maybe you should cut the nozzle of 2 more CHT nozzels and make them an extention
Just wanted to throw in my 2c. Your cross sectional area of the holes just exceeds that of the 2mm bore, however with three smaller bores you get an increase in total internal wall surface area contacting the melted filament, thus increasing the flow friction. This may have some bearing/impact on extrusion behaviour. Given the two examples with similar performance - CHT nozzle with standard spacer, or 3 hole spacer with standard nozzle, you're getting approximately the same length worth/same increase in surface area, and therefore flow friction. But you're essentially doubling it by using the CHT nozzle with the 3 hole spacer. That, in conjunction with the other technical hurdles as described by other commenters, could be a contributing factor in the reduction of overall extrusion performance with this combination.
I see Bondtech now have a CHT volcano nozzle. Be interesting to see how that performs in comparison with what you've already tested.
Wirklich mal wieder eine saubere Studie! Kleine Anmerkung: Die Dimensionierung der drei Bohrungen sollte nicht nach dem Kontinuitäts-Prinzip sondern nach Hagen-Poiseuille (Reibungsdruckabfall im Rohr) erfolgen. Dann kommt man in Näherung (dV/dt=konst.) zu r2^4/(3*r1)^4 = konst. und damit zu knapp 1,5mm je Bohrung. Damit sollte die Extrusionskraft in etwas konstant bleiben können.
Better option IMO is the high-flow spacer with a standard nozzle, because that would allow you to use hardened nozzles, including E3D's upcoming one with a diamond-like coating (DLC). The CHT nozzles are only nickel-plated brass.
Would you need a hardened spacer though as well? Perhaps it is not as crucial but it will eventually get trashed.
If you want to mess around with DLC nozzles and dont wanna wait, Phaetus already has a "DLC" nozzle
Ruby and Sapphire nozzles too, and 0.1mm micro-nozzles.
@@AmaroqStarwind i'd say the dlc is probably a better option as, because of the ruby, it is hard to get it in the same preferrable 60° angle for optimal flow characteristics like E3D's nozzles use, also Ruby's are expensive
@@BH4x0r Synthetic ruby and synthetic sapphire are both options, just like synthetic diamond-like carbon.
Also keep in mind that the entire diamond market is built on a scam.
The principle is similar to a "torpedo" that has been used in injection molding machines for many decades.
Hmm, so the patent is even inspired by existing technology?!?
Hot melt guns use it for long time.
Yesss! As a volcano user, the CHT was great but not so in converting all my systems away from volcano, now I'll just patiently wait for someone to make proper extension bores and can upgrade my volcano's into something even better!
It came to my mind with previous video on the subject. Drilling in nozzle's side might be tricky for someone without drillpress. I figured out that using flat piece of copper (hammered copper wire) and just sawing nothes in nozzle's top will be much easier. Would still need soldering though. Going this way would also lower the resistance as those copper strips in + pattern would work like slim knifes slicing through the filament on the entry. This could work for such extender/adapter as well with longer slits in its body.
Interesting to see the differences with the second test. Glad you added that, I wouldn't have expected your adapter to work after seeing the graph
This is great! And what makes the community such a great thing to be a part of. Thank you, Stefan.
Another superb presentation with clarity and technical excellence. I do have a Volcano head with a 0.8mm nozzle. Your investigation shows me a direction to go to improve print speed: A CHT nozzle and a straight through extension for its ease of manufacturing. Vielen Dank.
I noticed you screwed the spacer in from the nozzle end, which results in a cavity where the recess for the hex socket is. Wouldnt it be better to screw it in from the top of the block to remove the cavity? I'd have thought that cavity would have an effect on retraction, backpressure etc.
Good point but quite hard to do on an Hemera due to the installation order. It would be possible but I pain if you regularly want to change something.
@@CNCKitchen in your testing yes it makes sense to do it from the bottom because of the repeated testing. But for someone doing it once, would be better done from the top i'd assume.
@@ozcanison how do you get the heater block in the desired orientation if assembling from the top?
Have you considered using copper slip/copper anti seize. It's used on the back of brake pads and on the studs /nuts on an exhaust manifold often so it's very hear resistant but also due to it being copper has very high thermal conductivity so should be perfect anti seize for this application.
Use a small carbide endmill to start the off center holes. It is stiff enough, and has a flat end so it does not deflect.
I'd suggest to use solder (or even printing filament) to ease all the fancy drilling. First, fill the hex to the borders. Then drill offset hole (to make some off-center jig for it also would be a good idea). starting from flat surface, it wil be much easier. Fill freshly drilled hole with more melt. Repeat for second and third holes. Also, by this method you actually can drill overlapping holes, it should be good for performance, I think. Finally, heat up the spacer to remove all temporary material.
So interesting and counterintuitive! Very well done! You should try it with different nozzle diameters ass that may change the results
If I was going to modify the spacer, I would tweak your copper wire idea. I'd use a redundant heat block, and make a drill guide from it. I would tap any drilled hole in the spacer, and insert a grub screw, whose length was just shy of the diameter of the unthreaded part of the spacer. Once inserted into the heat block, the grub screw will be constrained. The threads of the grub screw will increase the surface area, and in theory, help melt the filament better than plain copper wire.
You should get a flat end mill to make the bottom of the whole flat which will help prevent the drill bit from walking
I can successfully overwhelm every hotend I own using nothing but the trash can model in vase mode with a high enough print speed and layer width. I also increase the print size so it fills the build plate.
What do I think? I think you are nuts! And I love it. Thank you, Stephan. You crack me up and I appreciate your videos, Sir.
love the work here. have you tried making a jig from an allen tool? one angled hole in it as a guide. drops in, drill, droop in clocked 2 sides, and a third time.
Really appreciate your dedication! An end mill is much more rigid than a drill bit - using an end mill (or for precision, end mill then reamer) to make your 1.2mm holes might be easier in the future.
I'm really impressed your home made high flow spacer worked so well. I thought the filament would impact the middle of the spacer and cause all sorts of issues.
You mentioned this may be the cause of the abrupt failure at higher speeds. I'd be very interested to see this same spacer but with the entry to the 3 holes bored out more so the middle meets at a nice sharp point like the CHT nozzle.
Great video and impressive work to manufacture your test spacers.
To anyone watching this today, bondtech finally makes full sized volcano CHT nozzles.
Shorten the drill bit to create the pilot hole to avoid deflection. It can be easily done by either buying shorter drill bits or by placing the longer drill bit deeper into the chuck..
Have you considered cutting a groove across the top of a standard nozzle and just soldering the copper wire up there? You could even bend it in a u shape to go down into the chamber. Maybe pound it flat to make it more like a blade.
I would try cutting the CHT nozzle as the spacer, and cut a volcano nozzle down to fit. This would provide the precision machined division to quickly melt the filament, then combine again into the standard nozzle. this might reduce the pressure enough to get a bit more performance before the extruder starts to slip.
Extremely useful video since it shows a lot about plastic melting inside the nozzle.
Extremely interesting!
Thanks a lot!!!
Well, seems like the optimal solution would be to place the heating element into a needle and and build it like an airbrush nozzle. Also having a longer straight end to get more laminar flow inside the nozzle. We could modify a cartdrige soldering iron.
Hmm...
You should try to make Volcano nozzle with perpendicular copper wires. Then you could make cavity closer to nozzle output and "CHT-like" system in top part to make similar combination to standard V6 nozzle + CHT adapter (which IMO performed best).
Great content as always, really makes you think deeper about how it all works inside. My guess is that first having some significant straight bore to get the material soft enough to got into the smaller channels, then the smaller channels to make sure you really get a consistent temp profile across the flow field, and then a fairly long and gradually tapering bore all the way to the nozzle, so it can settle into a nice Poiseuille flow, would be ideal.
Rather than the center punching, I was thinking it should be helpful to overlay a piece of flat metal when drilling your holes, so your drill bit is maximially clamped near the relevant spot.
i've been wanting to do the volcano-cht adaptor! glad to see someone did it
I just improved my volcano hotend by moving the temperature sensor from it's original bit more far from the heating element. I just drilled an extra hole for the sensor. Originally it was positioned between the heater element and nozzle which I don't find to be optimal.
I'd probably use more than one sensor.
Next time you drill something like that, try flattening it off and center punching the flat surface instead of messing with the pocket. You can fill the pocket with solder, part it right off on the lathe or even try filling it with epoxy resin so that you can drill straight through the resin and into the brass. Then you can remove the filler with heat and get your hex back. The simplest solution IMO - machine a flat face on ordinary rod, drill the bores and then cut a slot afterwards so you can use a flat blade screwdriver to install it. Great work on your testing, I suspect coming out of the 3 bores into a cavity and then re-entering the 3 bores of the CHT is the reason that test worked poorly.
Did he ever show how he lined up the three holes when the CHT and HF adapter were installed together? I think that even a slight misalignment of the holes would cause an increase in flow resistance.
The hex cavity would give the filament room to flow between the spacer and the nozzle.
Really loving the CHT series! Keep it up! Absolutely crazy effort on this, I can only imagine the frustration! Very interesting to see how nice the CHT is on its designed setup! Very interesting to see how all this pans out! I hope Bondtech does the CHT in hardened but I have a feeling that wont last long! Thanks again for the great video!
Brass M6 all-thread might be an more available option for stock material. A thin steel nail makes a great center punch and I rather hone a starting step onto a small drill bit to keep it centered. Brass hardens from work forming, simply punch a hex bit in and then tread thru a M6 cutter. Then Countersink the holes to finish...
How about turning a CHT nozzle into a spacer? There should be enough length in a V6 nozzle - you just need to part off the tip and turn the hex into an M6 thread. There will be a gap in the threads between the original thread and the thread that used to be hex, but it should seal between the sections OK
Might be worth trying out!
for improved manufacturing of the 3-hole spacer, punch and drill the holes from the flat side before drilling the indent, that way you're drilling on a flat surface instead of the faceted hex. and drilling the indent shouldn't be affected because the holes are symetrilac and therefor cancel eachothers effect on the drilling of the indent.
If you had a rotary broach you could make your own adapter from brass stock without using grub screws. drilling the three holes would be way easier using a four jaw chuck to drill off center before center drilling and then broaching the hex. Rotary broaches are kinda pricey but once you realize all you can do with them they don't seem so bad.
Nice, thanks!
Was wondering about that in combination with the rapido high flow adapter. I hope there's a way to make it fit there too.
Could you make spacer from CHT nozzle itself ? Just cut off front part of CHT nozzle.
Looks like sharpness of space between three nozzles where filament enters is important. Using CHT nozzle as spacer will make spacer perfect
would be expensive
now a supervolcano with a CHT, the real unstoppable combination
This with a Pellet Extruder Sounds amazing. Maybe i schould try it on my printer
i picked up like 10 of the CHT nozzles. holy shit they are badass. total game changer
you should make an insert to allign the drill bit, I can't say if a 3D printed one would stand up at that size, but it is worth a try.
Regarding the DIY manufacturing: Drilling the hole could be easier using a milling end. Also, if you are not shy grinding the drillbit, one could shorten it, so it can't deform as severly, as you showed on video.
wow i did not expect how interesting that was! i learned a lot thanks!
HI ,you could tig weld the copper wires quite easily and then there would be no problems with max temp.
You should use a center cutting end mill, when trying to drill the 3 holes. You won't get any deflection. But only to get them started then change to a normal drill.
Good job Stefan! I'? Great fan of yours videos. You make very good analysis, and lots of data which I got from your videos I use in my printing. In only one year I achieved lot of progress, from noob to expert and you have big contribution in this process.
Considering your machining time and buying the grub screws, drill press, mini lathe, drill bits, maybe it would be better to just buy the $20USD CHT nozzle standard bore spacer. Thanks Stephan for showing us the way.
Very interesting my dear Stephan ! Thank you from France
Your quest for faster printing is a good demonstration that all 3D printer owners would dearly love, though not just faster, but injection moulded like results. Of cause that's never going to happen with layer-by-layer additive methods :(
Great video as always! Would be very interesting to test some high flow hotends like mosquito magnum and drogon HF with and without the cht nozzle. These combinations could give extreme flow rates
One massively underrated bonus of this is the more permanent seal between heatbreake and hotend. Nothing about 3D printing has annoyed me as much as the lousy way heatbreakes are supposed to form a seal by pressing on the hotend.
Nice video Stefan, I got to similar conclusions. and currently run with 0.4 CHT and a single 2.0mm hole in my magnum equipped #VolcoMosq.. the highflow spacer + CHT ended up with too high forces, so the polymer stiffness and the extruder capability to feed the filament was the limiting factor for the most..
have you tried soldering blades into a vulcano hotend? got quite good results by this. Had to slot the nozzle and then pushed a blade into it. used some high temp solder afterwards. but also want to try a version without solder and slot in the future. neverless the resistence of the blade was way less then the drilled holes which seems to work better for me.
@@tobiask1390 as that will infringing the patent, I'm not going to try this typ of altering the nozzle..
dude i frickin love this dudes accent
Thee CHT nozzle is a realy cool concept!
Wow. Great work, thorough, well presented, interesting, directly relevant. Many thanks 🙏
Have you considered brazing the copper wire into a plated copper volcano nozzle to allow for higher temperatures?
Also, a copper nozzle has better heat transfer than brass, so it should have better flow and heat transfer to the wire.
Although, you have to remove the nickel plating with a wire brush or some abrasive fleece.