Finally upgraded my extruder to Eric Lien 's hurcustruder.

Finally upgraded my extruder to @Eclsnowman 's hurcustruder. The difference is night and day! I can now start a print and leave. No fiddling with the bed to make sure the plastic doesn’t jam. Planetary stepper just powers through. I also quite like the filament spool mount. Only complaint is that it’s much harder to change the filament.

I took the time to re-enforce my hotend (It could move slightly along the Y axis, resulting in some ribbing) and actually mount the printer board to the printer itself. I’ll eventually do the same with the PSU.

I printed a 30mm test cube, 0.2mm layer height, 40mm/s inner perimeter, 20mm/s outer perimeter, 50m/s infill. It’s alright; nothing really spectacular though. I would like to get those faces super smooth though, even at 0.2mm. Any suggestions on how to improve this?

Looking great. Love the Bowden pushlock adapter.

For the filament change it does take longer, I agree. But so long as feed is consistent I guess I take the trade off.

Clean prints. Nice job.

@Erik_Scott I have a “bird nose” on my classic Greg’s Wade’s pusher. It allows me to set the tension and then quick release whenever I need to inspect the gear teeth or change filament. Then when I put it back in place, then tension is exactly what it was before. If I’m going PLA to PLA, or ABS to ABS, I don’t need to mess with it at all. Something similar here would probably solve this problem.

@SirGeekALot I agree the quick release lever is a must have for this type of extruder. It allow quick disengage of clamp without touching the spring tension. So always back to the same compression after filament change.

@Erik_Scott Have you calibrated your E steps? There is tiny ripple in Y face. I wonder if there is any guide in tuning acceleration and jerk to eliminate this.

Weird, I failed to find “hurcustruder” via google… Where do you get it?
I need to discard my own one (that fails with a speedy 24V delta) and I was currently looking for an alternative…

It is from the HercuLien. Check the github reference at the community root page. It should be there.

@Jeremie_Francois it is actually hercustruder.

@Eclsnowman Doh! Should have gotten the spelling correct. It was late when I posted so that’s going to be my excuse. Thanks for the positive comments though!

@SirGeekALot ​ do you have any pics of your extruder? I’m looking for ideas on how to possibly add a lever to more easily change filament.

@hon_po ​ I have indeed calibrated my E steps, and I seem to be extruding the right amount. Off the top my my head, it’s about 480 steps/mm. @Eclsnowman ​, does that sound about right for a 5.18:1 geared stepper?

Sounds about right, but it depends a lot on the hobb gear diameter. Just calibrate as you usually would and you should be good.

@Erik_Scott this* is where I got it from and it has better pictures than the ones I took anyway. :slight_smile:

*apologies for the Takerbot link, but this is where I originally got it from.

I am printing it with XT (colorfabb), but it had a lot of trouble with the really steep concentric overhang of the body… This material is great, expect for bridges where it fails a lot (I never was able to drag more than 1-2 mm of it in the air). Still should be fairly OK as I expected.

@Eclsnowman ​ good, I’m in the right ballpark then.

@SirGeekALot ​ thanks for that. Seems pretty clever. I may give it a shot.

@Jeremie_Francois ​ I didn’t have any trouble printing it with PLA. I do have a fan + duct directly cooling the extruded plastic, however, which helps a ton with overhangs like that.

@Erik_Scott yeah no doubt PLA would be much easier. But I wanted a rock solid stuff, and temperature resistant (which is why I opted for XT). WIll most probably re-print some parts in CFPLA. if it works fine and does not heat too much (working with 24V at high speed…)

All mine are abs. I can print the assembly of all components at 80mm/s easy, which is why I love abs… It just seems to run better at high speeds than PLA.

I highly suspected that – but ABS is the only material I never print. At 200mm/s (nozzle=0.6mm) my own extruder completely fails, but I highly suspects the MK8 chinese bolt is crappy…
Not sure 1.75mm gives enough grip btw.
Ref: https://github.com/MoonCactus/fisherstruder/blob/master/fisherstruder.jpg

@Jeremie_Francois very cool extruder design. I like how compact it is.

@Eclsnowman glad you like it! Indeed the idea was to be very compact, easy to print (2 parts), and compatible with a reductor – an interesting challenge I was given by a friend. The shape quickly came out (could not have 3 screws b/c of the place it stands in our deltas - has to be flat). I thought about making it even hollower and faster to print as it is really tough, but it would better benefit from a quick lever like yours (no easy solution here). I would improve it if the grip suited me, but it sucks. I would better go and print myself another good old rollerstruder instead. Hey, what would be your recommendation for a very reliable 1.75mm bolt?

@Jeremie_Francois bolt?

@Eclsnowman lol, who on earth is still making his own bolts? :wink:
Not sure it would be easy for 1.75mm filaments but it is worth the try. … will check this week end and tell (I am sure I can do at least as bad as what I have here)