Small question about material feeder ...

[mnis 11]

Hi guys

I would like to know how the material feeder can detect the material flow requires too much force. A mechanical solution is not apparent. Monitors the electronics the power requirements of the step-motor? Is triggered at a high current demand Retract (ticking)? Or is the step-motor, a special variant?

Markus

[mnis 11]

Thank illuminarti, your explanations are detailed and easy to understand, so thank you for your effort.

I still use Cura and firmare v13.12. Cura provides under: HELP> CHECK FOR UPDATE, no new version. The message is always: YOU ARE RUNNING THE LATEST VERSION OF CURA!, That does not matter to date. Some reports of problems with the latest version Cura (v14.01 ... 14.01.x.?.?.?) Have confused me a little. And due to time shortage I can not read everything, unfortunately. So I do not know if the latest version works reliably.

Last Sunday I had to stop printing, the machine did not stop immediately, which I already knew. When it stopped, the machine has pulled the thread out of the hot-end wide and thin. I had to completely disassemble a second time the print head so. Otherwise I would not be able to remove all residues. Since I had worked with much lower temperatures and I already had a little routine, it took little more than ten minutes. The machine was so quickly ready for use again.

I, however, noticed something during my work:

The PTFE piece (cold-end ?) Above the hot end is similar to a funnel. The lower end was very very tight, perhaps too tight. Anyway, I was dilated with a small hand-drill (0.118inch) the opening bit. Previously, the inner diameter was slightly lower, I could clearly feel. At first I thought it was a mistake to do so.

But apparently I've done the right thing, because:

I suddenly can print at much lower temperatures without missing details. On the contrary, the typical click of the material feed is seemingly gone. Before I already got from time to time massive clicks at 35mm/s / 210 degrees. Now I can go at the same speed with the temperature well below 200 degrees, without hearing just one click. Besides, the object structure of my prints is now much cleaner overall. Even narrow walls look much smoother.

All the test I have done with the Cura defaults. I only have speed, extruder temperature, bed temperature, and the Adhesions-aids for direct printing on glass changed.

Maybe there are manufacturing tolerances with respect to the cold-end, which should be checked during (...before) assembly of the Ultimaker2.

What do you mean?

Markus

[IRobertI 521]

You can always find the latest official build here: http://software.ultimaker.com/

I think there was a bug in some version of cura which didn't correctly detect new updates. I'd recommend updating as there have been a few bug fixes.

Thanks for reporting on the teflon piece being too narrow. That's the second time we've seen that now, definitely something to look out for. The question is why and when it happens.

 

[mnis 11]

Thank IRobertI

Then I'm going to get the latest version Cura take a closer look at the weekend.

 

If we want good things to get better, then we have to share all the experiences.

Back to the Teflon Piece:

It looks like it would be the easiest solution to problems of which some users report.

What is the diameter to the lower end of the PTFE funnel, called cold-end, have exactly? What was provided? Is it an easy-to-find part or specially made for Ultimaker machines?

Markus

[mnis 11]

The Teflon funnel was only a small part of the hard road to success.

After the trouble did not end and again gaps in objects were visible, I finally found the best solution for me.

The step motor has lots of power in any case. If too much tension in the Bowden tube is formed, the filament slips back sometime mercilessly and then parts of the currently printed area are mostly faulty. Also the increase of the force of the contact pressure roller does not improve the situation. Therefore, it is also often recommended not to increase the pressure by means of the adjusting screw.

And everything is so easy. You just have to know.

At least the first 50 millimeters below the material feeder must run straight. How do you solve the problem is not really matter, only the result counts. Immediately after the implementation of my tips, the filament transport has much more power for constant and easy material feed.

Wrong combinations of temperature and speed lead to further poor results. Known issues with lousy filament quality can not be resolved. But all the symptoms will be less pronounced.

May the fight against ticking noise and damaged prints begin.

Below the pictures to my solution:

Try it ...

[IRobertI 521]

Interesting idea. I have some spare bowden tube lying around from my UM1 that I could use to test this.

 

[mnis 11]

Yes, it works amazingly well. For me it is also the most space-saving solution. I can not put a filament below or farther away from the machine. Until now, this form of optimization has the highest impact. I guess there are already over 100 hours with no ticking. I do not miss that sound, anyway.

[gr5 2,240]

VERY INTERESTING!

I want to make one of these. For now I do it this way but I like your way better!

 

[mnis 11]

Thank you :smile:

I should mention:

The plastic tube must not hold the Teflon tube strong. The inner diameter can also be chosen slightly larger. Because the filament transport is still automatically pulls the hose up. Again, this has advantages for easier material change and a proposed material retraction is also easier for the machine.

More details you can always find below the images in my gallery.

Markus

 

[IRobertI 521]

I had high hopes but sadly it wasn't the solution for me. Didn't really make any difference on my printer. I still think it's a combination of a weaker extruder overall and the friction inside the actual extruder.

It wouldn't hurt if someone else gave it a try though since it's obviously working welll for mnis.

 

[mnis 11]

That does not sound so good, but it works for me for sure. I have nothing of it when I invent stories ...

I would also like to know whether others have tried. Try it please and shares your experiences. All tests were previously only with original Ultimaker-PLA, no idea if there will be new problems later with ABS.

I also discovered in my machine, which is the engine of the material feeder longer than the other engines. Do all UM2's integrated a bigger step motor?

There are huge differences in quality even with step motors. Maybe some are actually too weak or faulty. A friend (electronics-maniac) has already purchased several apparently identical engines with enormous differences in performance.

Nothing is impossible. The entire way to the heating chamber should be examined. The filament must be able to be moved up through the Teflon funnel with little hand strength. For a test, you can remove the gear from the step motor. The screw for the pinch roller should be rotated until the white marker is at the top. It is enough for the weakest setting.

My problems are definitely history. Currently running a 21 hour test object. With over 3100 Layer (0.02mm) a big job for a small part. Already over 12 hours with no apparent problems and about 10 hours it will need to final completion. My machine is on the desk, next to my laptop. Ticking is definitely no longer perceptible.

Markus