Neotko FatIRobertI Bondtech Adapter Feeder for UM2+ / UM3

[derbroti 4]

Maybe I can print a cube 10x10 and measure it so we can check the differences so you can use cura/s3d horizonta expansion options

 

Thanks! I will do the same - let's see

[derbroti 4]

It took way too long (life came in the way) but I printed 3 calibration cubes (10,15,20mm) and all of them were spot on (highest deviation was 0.04mm)

[neotko 1,415]

It took way too long (life came in the way) but I printed 3 calibration cubes (10,15,20mm) and all of them were spot on (highest deviation was 0.04mm)

 

I have changed all my extruders to zge direct drive. You could try to print the joke with + 0.10 horizontal expansion, that should make the rumblings get away. Sorry I have dismantled all my feeders and it will take quite some time to assemble them.

Sorry men I'm so freaking busy lately.

One thing for sure I think all my printers before where overextruding a 0.10mm aprox. That could explain why that design has so much play when printed right.

[neotko 1,415]

It took way too long (life came in the way) but I printed 3 calibration cubes (10,15,20mm) and all of them were spot on (highest deviation was 0.04mm)

 

Just did check the step files, I see the problem. I will edit this post with a link to the possible fix, horizontal expansion won't fix it since is a Z problem. Give me 5mins or so and recheck this.

Edit:

Try this

https://www.dropbox.com/s/s9x2a8e0wett1kh/Joke-Fix-test.stl?dl=0

I'm 99% sure that should fix the issue. I left way too much play so it can swift.

There are 2 versions, one is slightly shorter, or longer. The short one might work better for 2.85 (less chances of flattening the filament if you use a spring too strong, that also could explain why your dances too much, is normal since is pushing so hard that the force goes to the weak point of the design, I use a very light springs and depend on the Latch lock to leave the distance fixed and use the spring system to compensate for filament size variations, but without pushing too hard.

If when you print the parts you fell that they have too much friction to install, sand them slightly until it goes ok, but without play.

Btw thanks for the feedback men!

Edited March 13, 2017 by Guest

[derbroti 4]

Try this

https://www.dropbox.com/s/s9x2a8e0wett1kh/Joke-Fix-test.stl?dl=0

I'm 99% sure that should fix the issue. I left way too much play so it can swift.

 

This one is better

After a little more inspection: the part is still too wide: so I have nearly no up and down rocking but I can rock it left to right (that's why my joke is so "bend" to the side when I feed filament into it (I hope it is understandable what I try to say)

By the way: I think the edge of the mating part (the arm) is not flat (on the side that was related to the up-down rocking issue), so it can still rock a tiny bit up and down (during retractions) - that needs further inspection.

However, when printing the new joke I had a weird underextrusion problem - I have to look into that before printing again.

 

[...] if you use a spring too strong, that also could explain why your dances too much [...]

 

Actually my spring is too soft - I had a short one laying around from my hardware store, because my bolts are too short for either the original UM2 feeder spring and the 2+ spring...

see:

the darker short one is the one I am using. The other is the original UM2 feeder spring.

Edited March 17, 2017 by Guest

[neotko 1,415]

It shouldn't move left right indeed. Are you sure the sandwich parts are making a good lock? I ask because one of my fears when I made this was that the pressure could separate them. I think the main issue is that I never used 2.85 bondtechs, and 1.75 uses less torque, but more revolutions. The pressure should be less than the original feeder, in fact it should work fine without a spring. Can you check how the filament pass thorough by hand without the spring?

[neotko 1,415]

Btw also tomorrow I'll have more time. I'll check the lateral play to make it fit, so the users can file it until it goes in/out smoothly.

[Rastamonk77 0]

Hi there, I've just print and installed 2 of the Neotko FatIRobert on my um2+ i'm having similar issue as @derbroti with the 2.85mm.

 

I have lots of play  ( that I was able to resolve with some washer) and  reprinting a the arm.... but no matter what I'm getting some serious under-extrusion issue.

 

I've been playing now for 2 days, taking apart,checking an tuning my Thinkergnome firmware but i cannot seems to resolve the issue.

 

Any one that can help on the matter?

 

[neotko 1,415]

8 hours ago, Rastamonk77 said:

Hi there, I've just print and installed 2 of the Neotko FatIRobert on my um2+ i'm having similar issue as @derbroti with the 2.85mm.

 

I have lots of play  ( that I was able to resolve with some washer) and  reprinting a the arm.... but no matter what I'm getting some serious under-extrusion issue.

 

I've been playing now for 2 days, taking apart,checking an tuning my Thinkergnome firmware but i cannot seems to resolve the issue.

 

Any one that can help on the matter?

 

 

Sorry can’t help much, I don’t use this feeder anymore so dunno. Maybe I can send you the step files so you play with the errors I made?

[nerdwarrior 19]

I've printed one out and assembled it, but haven't gotten around to actually installing it, so I can't speak with certainty whether I have the same wobble or not. From what I can tell, however, my feeder seems solid and not wobbling.

 

Some things that I did to mitigate wobble from the start include printing everything with a horizontal expansion of +0.1mm and printing both the "Hands" and "Joke Fix Test" (above) files, which gave me three parts to use. I then tested to see which one gave the best fit.

Hope that helps!

[Rastamonk77 0]

5 hours ago, nerdwarrior said:

I've printed one out and assembled it, but haven't gotten around to actually installing it, so I can't speak with certainty whether I have the same wobble or not. From what I can tell, however, my feeder seems solid and not wobbling.

 

Some things that I did to mitigate wobble from the start include printing everything with a horizontal expansion of +0.1mm and printing both the "Hands" and "Joke Fix Test" (above) files, which gave me three parts to use. I then tested to see which one gave the best fit.

Hope that helps!

Thank you both Neotko and Nerdwarrior for the replay.

I've taken it down again last night... I've managed to make the whole thing wobble free with a couple of washers... And I think I find the issue by exclusion.

It seems the shaft/adapter has a bit of play inside the bearings...in addition when the the grub nut is tight it (due to the flat sides) it pushes the gearing offeset. Those 2 are causing the moving away the gearing from the centre of rotation....and therefore uneven pressure on the filament.

I'll try today at work to CNC 2 new shaft out of aluminium.

@neotko... it still a great model model...but may I ask you what do you use now a s feeders?

Thanks

[neotko 1,415]

@Rastamonk77 and anyone else interested, I did upload a full step file assembled where you can pick anypart needed (I hope) 😄

 

https://www.youmagine.com/designs/neotko-fatiroberti-bondtech-feeder-for-um2-um3

 

File is:

Um2plusbondtech Full175 & Um2plusbondtech Full285 - In Step format

 

Happy editing! Cheers!

Edited December 19, 2018 by neotko