Under Extrusion issues

[gilliajb 0]

Printing PLA at 210 on an UM2E will have a number of prints that run fine with no issue. Then will have one print like this. New to 3D printing but this appears to me to be an under extrusion issue.

Have had the printer less the a year and have are on our fourth coupler. I do not know how frequently this needs to be done.

3rd Coupler (used with print in image above)

Is the image of the print solely and under extrusion issue? How often do the couplers need to be replaced. I do not view our printer as being heavily used. Some of the print jobs are running up to 30 hours but the machine will sit idle for a week (est.). I was looking for the file "MiniCalTest" but only able to find "._MiniCalTest.gcode" on the card. Any help/suggestions greatly appreciated.

[neotko 1,417]

Hi and Welcome,

According to https://ultimaker.com/en/resources/19619-ulti-evening-maintenance'>https://ultimaker.com/en/resources/19619-ulti-evening-maintenance'>https://ultimaker.com/en/resources/19619-ulti-evening-maintenance'>https://ultimaker.com/en/resources/19619-ulti-evening-maintenance a PTFE coupler can last 100-50h depending on use. Also if your prints needs to be near 250C it will die quite fast.

The new TFM couplers, that you can get at any ultimaker distributor + fixed size spacer, can last 500-2000h print ours, that might be what you need, because on your photo the ptfe coupler it's really dead, like dead dead.

The underextrusion from a damaged coupler it's because the inner area constricts creating more friction between the filament and the coupler, so any material need's more heat or force to keep the extrusion ratio, hence it underextrudes.

Also... Before all this, could you check that the little fan behind the hotend it's running as soon the Hotends it get's 40C ? Because if the small fan it's failing, or running slow due dust, it might be one of the problems that it's causing your couplers to die so fast.

If everything else works as it is, I would highly suggest to buy a TFM + Fixed spacer (you can just print it, but if you get it from ultimaker it will be made in aluminium, and that's always a plus to keep everything with precision. If you go this route remember to print https://ultimaker.com/en/resources/19619-ulti-evening-maintenance that will allow you to install the TFM coupler without much problems.

[gilliajb 0]

100-50h compared to 500-2000h print hours is a huge difference. I am not surprised by our problems then. Our average print time for one part is around 30 hours. We have switched to the new coupler but what is this "+ Fixed spacer". There was a spacer that was on the original print head but we are using the olsson block. Is this still applicable? We did verify the fan is running and kicks in at 40C. We had to replace this already as fan started making a lot of noise and assumed the bearing was going out. Excellent response and thank you.

[neotko 1,417]

The spacer it's

That metal part substitutes the spring.

Just send a mail to the guys of fbrc8.com there in USA linking this post, they sure have the fixed size spacer and the plastic guide to install it that comes with the Maintenance Kit.

To install the TFM properly you need that plastic guide (or the printed version available on youmagine)

Check this guide to see how it's all assembled with the fixed spacer

https://ultimaker.com/en/resources/22188-how-to-replace-the-tfm-coupler

The plastic assembly helper 'to print version' https://www.youmagine.com/designs/ultimaker-printhead-spacer But double check the comments from @sandervg about how to print/use

Edited September 15, 2016 by Guest

[Gnevko 5]

Hi and Welcome,

According to https://ultimaker.com/en/resources/19619-ulti-evening-maintenance a PTFE coupler can last 100-50h depending on use. Also if your prints needs to be near 250C it will die quite fast.

 

It is also true (100-50h) for UMO+?

Edited September 22, 2016 by Guest

[neotko 1,417]

It should since is the same material. But on umo/umo+ the feeder is way overpowered so it takes more time to start causing extrusion problems.

3dsolex makes a umo/umo+ coupler of TFM

Material that is should last much longer (I personally never tested it since I moved all my hotends to um2)