1.75mm filament overextruding

[SpeedyDad 0]

I built an aluminum extrusion UM2. This one:

http://www.thingiverse.com/thing:811271

I am using UM2 main board and the UM2 feeder knurled sleeve, I've set the filament diameter to 1.75mm in the on-screen setup and in Cura. When printing, i am getting massive over extrusion. I have to set the flow rate to 55% to get normal flow. I did a 100mm test extrusion using Pronterface and it extruded 180mm which agrees with the 55% above. When I do an "Insert Material" it tries to push way too much material through and ends up chewing through the filament when it can't push that much.

If I set the filament diameter to 2.85m, it gets closer to proper extrusion but still not correct.

Is there a way to set the steps per minute somewhere in the software? I know how to do it with my Prusa i3 but adjusting firmware in the Ultimaker seems to be a mystery. Can I do an M92 command in Pronterface to adjust it?

I have tried the latest firmware, an older version and the Tinker firmware with the same results.

Thanks.

[IRobertI 514]

The UM2 is built for 2.85mm filament so it's not strange that you're getting strange results with 1.75mm.

Yes, you can use M92 in Pronterface to set the correct e-steps. Don't forget to save with M500.

[neotko 1,417]

@IRobertI esteps don't change from one filament to another unless you change the diamond shaped feeder for a mk7.

Also if you didn't changed the hardware head/bowden/nozzle to print 1.75. Then you have a world of problems with toons of filament flowing up/down on a bigger area, with filament also bending inside the tube, retracts failing if the heat/speed isn't right. You can, but you will get gazillion of troubles.

Also the tension for 2.85mm filament isn't the same than for 1.75mm so for starters the filament should be slipping on retractions and/or if the temp it's low and generates force the filament will start to twist on itself on the bigger bowden and most probably will split in two inside the bowden (hysteresis).

Edited October 15, 2015 by Guest

[SpeedyDad 0]

OK, looks like I should have given more info.. The machine is fully set up for 1.75mm filament. I am running the 1.75mm version of the E3Dv6. I have the 1.75mm version of the iRobertl feeder with the stock UM2 feeder sleeve on the motor. I know the UM2 normally runs 2.85mm filament. I have set the onscreen ABS setup to 1.75mm filament so it should be feeding properly. Tension is proper.

I'm starting to wonder if Ultimaker uses a different motor for the feeder motor with different microsteps?

[neotko 1,417]

That sounds nice.

My experience it's with umo+ (almost same hardware) I changed it to 1.75mm. The overextrusion should mean that the filament size isn't well set. Have you tried to RepRap Flavour instead of UltiGcode? This way the filament size parameters are set by the slicer, not the machine flow control?

Also juat in case. Check that when using the stock feeder 'thingy' bolt, with 1.75mm I ended going to mk7 because the filament tends to slip to a side and the bearing crushes it or slips.

Edited October 16, 2015 by Guest

[SpeedyDad 0]

I'm going to try setting the e-steps first. I built the Ultmaker because  wanted the symmetry you get when the hardware and software are made by one company.

I tried a MK7 because the larger diameter should have reduced the over-extrusion but didn't like the way it fed. Much more skipping than with the UM2 feeder sleeve.

I'm currently printing parts to build another extrusion frame Ultimaker based printed but I'm moving the electronics from my Prusa i3 in to it. Should be interesting to compare results.

Edited October 16, 2015 by Guest

[SpeedyDad 0]

That worked. I now have much better filament flow through the machine and while printing. I can now also use the change filament option without it trying to push too much through.

[hakangurbuz 0]

Hi, I'm trying to same thing now, how can i fix this problem ? Can you explain how could you do this ?