Some things to work out with the swinging extruder, but its printing. Waiting on a heatbed that supposedly arrives tomorrow. Did some calibration and test print for extrusion due to again having an all new setup, almost, sort of. Hotend is new to me, E3Dv6 from the E3D web store, Motech 1.68a stepper is new to me as well, new drive gear for good old B’struder. I will probably go back to old drive gear version for testing to keep it simple even if it works worse, need to see what the other changes are doing independently.
Is the power supply 12/24V?
Tks
12v 850w ATX, its running 2 Duets (8x stepper motors, 3@1.7a, 3@1.5a, 2@1.4a with 30w hotends and one heatbed, soon to be 2 heatbeds. I think it’s still under its rated capacity with all that, barely.
How is that linear motion system working? Might give it a shot if it seems to do a good job. I saw your thingiverse page on it.
The delrin bushing carriages are the most reliable thing I have had to deal with over the last 2 months of printing. Delrin bushings in extrusion works reliably and consistently. I am sure it helps that since I designed them I know exactly how I intended them to function, but they are so simple I am pretty sure most can use them and ‘get it’ as far as what they can do if adjusted properly. they stay tuned realy well using a threaded PLA thumb nut printed out. 2 metal nuts are ok but the outside one being plastic allows it to compress and lock the preload really well. I have had really great success with M3 threads tapped into PLA, seems really strong better than injection molded ABS threads for sure. very few have stripped out, and it’s a 5 minute print to mek 4 more so MEh whatever I like PLA threaded nuts.
@Griffin_Paquette if you’re going to let me know, I need to update the thingiverse post with the newest parts. the ones on there are good, all used on Unit 1 succesfully, but I have some slightly improved versions, just a little weight removed here and there from areas outside force paths in structures. A version of the motor corner that allows the motor to be closer to the belt path, less cantilever to the belt gear on the shaft, minor stuff like that, nice but not necessary little improvements.
I’m interested. 2020 or 1515 extrusions? I want to use 20mm
its all designed for OpenBeam 1515, sorry that is just the stuff I had when I started. I want to do a 2020 version, but its a different diameter delrin rod as base material as the 2020 t slot is wider I believe. I guess some day I need to do that as it is the far more common material for good structural reasons.
No worries! I might still give the delrin sliding a try. I know how slippery the stuff is against metal. Where do you buy yours from? Maybe they have some that would work with 2020
its available in all kinds of sizes, round square and rectangular, its a stock material for a lot of industries part making. suggest just google Delrin acetal rod and pick a materials supplier nearest you or that has good prices. Real name brand Delrin from DuPont is better as it has a higher durometer rating than off brand similar polymers marketed as reppplacement material, they are close and will work well I am sure, but the stuff is cheap enough just usse the better harder material. It’s more expensive off some market like Amazon or in small quantities but we are talking the difference between $2 a foot or 10$ a foot and you only need 12 sections about 1/2" or 10mm, not even carefully matched as they work on the OD not the length. They stick to the PLA or whatever plastic mounting brackets far more than the metal, I made covers, did not need them the delrin can just stick out or be recessed a bit and it really doesn’t matter.
Super simple, super effective. If and when I see any wear on them, loosen compression thumb nut> push bushing out with allen wrench from bottom> and replace by simply pushing old bushing in rotated 1/2 to use the other side, the radius of the bracket will grip the unworn parts and let the flattened track areas from the 2 aluminum edges to just be out of the way. Not sure how many turns one could use before it was worn to replacement, have seen no wear at all so not holding my breath. Its like 30 seconds to replace the entire carriage bushings all 4, another minute or 2 to set the preload back to where you had it, which is fairly easy to do by feel and does not need to be super precise as long as it’s in a resonable range of slight compression, versus actually too loose which will affect positional accuracy.
If you want to use 2020 just get the extrusion, measure the T slot and maybe use some know size models that match the material you will buy, nylon spacers from hardware store work as bushings in a pinch and will work as substitution models to make a test bracket and then buy the appropriate outer diameter delrin for use as the actual bushings. Nylon is ok, just doesn’t feel as ice skate like slippery as the delrin. But in a pinch any 1/4" semi slippery bit of round anything will work with the 1515 design, it will just need to be slightly larger OD for 2020 as the 1/4" (6mm?) sinks to far into the slot and will compress and bind, it needs to be about 2:1 OD of bushing larger than the slot and it should be good slide. The T slot should ideally have a rounded edge as well, to sharp is going to bite into the delrin to unknown effect, it actually might not matter just establish tracks in it and require a little tuning now and then due to reduced surface area wearing faster. that said it might not as I have seen zero wear so far on my delrin bushings, smooth aluminum just polishes them, and they polish back, does not seem to be losing material or making an indentation at all.
Awesome writeup!! Your documentation has always impressed me with this build. I will try the 2020 extrusions with 1/2’’ diameter delrin rod. Looks like a very interesting system. I’ll also use black anodized extrusions so hopefully it will stay slippery against it. I’ll keep you posted on the build. Was in the middle of making a Kossel and decided to go my own route instead… Dual extrusion with a smoothiepowered board and heated bed. Just gonna go all out on this one and I lvoe your setup so figured I’d pull from it.
@Griffin_Paquette in Arnold Schwarzenegger voice “DO IT GRIFFIN!”
I am glad to help with any questions along the way. Its all pretty simple it just requires a few prototypes of the bracket to get spacing right. You want to have brackets that slightly compress the delrin on the extrusion, allowing spreading internal nuts on fine pitch machine screws as compression preload adjusters, and plastic thumb nut on outside to mash down and lock the setting. All the features of the best 4 channel bearing or IGUS bushing setups just easier to access adjust assemble and manufacture on a DIY scale.
Also like $5 bucks for the entire setup if you got the Delrin fairly cheap. I had it leftover from a plastic milled miniature model steam engine project that eventually had to be done in metal (milling plastic just basically sucks, heat is a constant issue) so it was actually pretty much free as that material was paid for and used and the bushings made from a scrap short section. I was thinking of buying like $200 a unit 4 channel rails after researching, having built a Mini Kossel frame, I had the delrin, I was bugged to buy rails I knew were sort of out of specification from the manufacturer to be mounted vertical and not loaded by gravity with only 2 channels. Held the delrin in the t slot and slid it around and thought, ‘shit, this is going to totally work screw the damn round ball in a round channel BS anyway’.
I machine, I do not find round balls in round channels on any machine that needs to make other machines unless it is rotational stability only, Mills and lathes slide on precise surfaces because round balls in round channels SUCK at positional accuracy. I know the cost loss crowd hates it when I talk like that, but damnit its true.
@AlohaMilton , heavy stuff you have.
The you have one. Get from here is really cheap : http://www.3dprintmanual.com/best-3d-printer/