ABS Gear doesn't hold dimensions  

RE: ABS Gear doesn't hold dimensions

I ment cone not comb

RE: ABS Gear doesn't hold dimensions

How are you printing that?  Which side on the build plate?  Are you using supports?

My first hunch is either lack of the so-called elephant's foot compensation or too much of it, depending on how it's oriented on the plate.

ABS is known to shrink a bit when cooling, but it should do so uniformly.

RE: ABS Gear doesn't hold dimensions

This is the way I am printing that thing.

Support everywhere.

Additional information is that I am printing that with 100% infill.

There is a small piece of the gear (where the axel go through) that is outstanding outside of the gear and that causing supports

RE: ABS Gear doesn't hold dimensions

My first suggestion would be to use a draft shield.  There may be some inconsistent cooling and that will help keep the print temperature stable.

RE: ABS Gear doesn't hold dimensions

I forgot to mention that I have a enclosure already, but on top of the enclosure I have a fan which suck all the air from enclosure and push it outside the room, I try again but this time I switch off the fan. Maybe this is causing the air draft. Let's see.

RE: ABS Gear doesn't hold dimensions

I've got a similar enclosure and have found adding a draft shield is beneficial.

RE: ABS Gear doesn't hold dimensions

I see what you mean now. Let me try with draft shield. Thanks

RE: ABS Gear doesn't hold dimensions

For sure switch of the fan, circulating air is the worst thing for ABS. Try to set the Skirt in slicer for the whole height (in default just for two layers). In general, I had quite bad experience with ABS gears, the teeth where damaged too soon. I do not have PC or Nylon, but had a good result with PETG with Carbon Fibers.

RE: ABS Gear doesn't hold dimensions

To me your photo looks like very warped. I once had a similar issue printing PC (Polymaker) and found out, that it helped to print on a raft about 2 mm high.

That was the part I had problems with:

And after printing using a raft (~ 2 mm high) it was ok:

I would also recommend to use draft shield.

Best regards, Clemens

RE: ABS Gear doesn't hold dimensions

@milos-v

have you been using special print head for the PETG with carbon fiber?

BTW. I did a try with draft shield and fan turned off completely, the result was a bit better but still warped. I give up and went for PETG which again was warped, but barely visible.

RE: ABS Gear doesn't hold dimensions

@przemyslaw-niewiadowski

Give it a try - use a raft. Try a height of 2 to 3 mm and check if it is going better (again with fan off and draft shield).

Best regards, Clemens

RE: ABS Gear doesn't hold dimensions

Not sure what is exactly draft shield, but in PrusaSlicer the skirt option do a lot to protect against the ambient air flow. 

For PETG with CF you should have hardened nozzle, but if I print such a small thing once, it does not matter. I use the standard one.

RE: ABS Gear doesn't hold dimensions

Draft shield is like a micro-enclosure to keep the temperature of the print more stable.  Both PS and Cura have it as an option.

In PS it's under the Print Settings, Skirt and Brim.  I used it regularly with ABS before I got the actual enclosure.

RE: ABS Gear doesn't hold dimensions

Ahh, haven't realized that there is a special checkbox for this, always used the skirt height option.

RE: ABS Gear doesn't hold dimensions

Both are doing completely the same - the checkbox is a little bit less work to set up.

Best regards, Clemens

RE: ABS Gear doesn't hold dimensions

I was about to try with raft, and I double checked the fan is off, but while printing the cooling fan was switch on and was blowing.

Is there any other option I forgot to switch off?

These are my setting:

RE: ABS Gear doesn't hold dimensions

Is the fan running the whole print or only during printing the raft - not sure, but maybe during printing the raft it is using fan speed for bridging? I never had an detailed look at this. Sure there are others who now that better.

Best regards, Clemens

RE: ABS Gear doesn't hold dimensions

In general, ABS tends to shring with or without a shield.  

RE: ABS Gear doesn't hold dimensions

Thank you guys, for any help.

Final result is that the gear still shrinks at the bottom, but after applying your suggestion (raft, fan off, draft shield) it a lot better, so I leave that information for anybody how probably will be looking for some ideas.

Personally I probably will end up using PETG or PETG+Carbon and exchange nozzle to proper one.

PS. As @clemens-m suggestion, fan was switching on for bridging.