[Solved] Extruder Skipping Steps

[Soynuts]

I have been battling a problem with my extruder skipping steps with a e3d Titan. No matter what I try, I can not pin down the problem. I had been battling this same problem for the past 4 months and thought I had it resolved.

My X axis motor had died on me, so I moved the extruder motor down to it and put in a nema 17 pancake motor in for the extruder. It skipped steps, so figured I just need to get a new nema 17 motor. Wired the new one up, seemed to work, and started a test print. After 30 minutes I had noticed nothing was extruding and it was skipping steps.

Cleaned out the nozzle and set the temp up from 235 to 260 (I print with MG94 ABS). Still skips like crazy. My motor current is set to 165, thought I should try a little more juice and put it to 175, no change, so put it back down. If I manually extrude with the titan gear, it moves smooth like butter. But if I let the motor try to do it, it just skips.

Motor: [img]http://i.imgur.com/TI6YvRX.jpg?1[/img]
Fan attached to motor: [img]http://i.imgur.com/5gWNlcJ.jpg[/img]
Raspberry Pi heatsinks on all motor drivers plus 40mm fan blowing across: [img]http://i.imgur.com/9na0nOc.jpg[/img]

Video of me manually extruding it: https://www.youtube.com/watch?v=-CjBT_PknOQ
Video of the motor trying to extrude: https://www.youtube.com/watch?v=8_TZA9Z5spM

I'm not sure what else to try at this point.

[joe]

Can you extrude with Bowden tube out of the hotend? Did you change your steps/mm in the epprom for the Titan?
Could be a wiring issue
And clean up that wiring! Get a fan on the back (back side of the Rambo)those stepper drivers . That is where they need cooling.
Also you have a 3D printer, why is that 80 mm fan in a chunk of plywood? Make a housing for it with your 3D printer!

[Soynuts]

This is an upgraded v1. There isn't exactly much room behind the rambo board where the psu is as it is.

It's hard to make a housing when the printer does not work. My overheating issue is gone, and that is all that matters at this point.

The titan steps are currently set to 422.

[Soynuts]

Oh, and taking the bowden out of the hotend does not make a difference. The extruder motor still skips steps

[Xenocrates]

So, Soynuts, I'm going to make a few suggestions. You're free to listen or ignore them as you please.

1. Increase stepper current for the extruder. If you have issues driving it with nothing but the bowden tube, either the current is insufficient, or or there's a mechanical issue. With a fan on there, you should be able to eke out a bit more current, which means more torque.

2. Check the width of your hobbed gear track. If you have an early titan, it may have a manufacturing defect due to a bad tool. Make sure you have a nice wide track there. If you're unsure, send E3D a picture (Or Tim Elmore at Filastruder should also be able to identify defects). If it is the problem, either contact your seller or E3D for a replacement.

3. Give your Rambo some breathing room. Try making some longer spacers and getting a fan back there. Maybe once you have the extruder reliable again (And maybe make a backplate that has ducting for a fan that is outside of it. There is space in the V1 for hardware in that bay. Give it a shot.

4. Would you mind telling me what generation of E3D that is, as I've never seen a orange molded fan shroud on them (This may betray that I got into printing after the V6 release)

[Soynuts]

Another update: I completely removed the titan and turned the motor on and it was not spinning at all but still making those noises. So thought maybe the wiring was having an issue delivering proper current. Lopped off where I had soldered and resoldered again making sure the connection was strong. Now it is spinning by itself. So my problem may have just been bad wiring/soldering of the new motor. Going to try again with the titan all hooked up. If not I will try your suggestions Xenocrates.

1. I'll try this if I still have problems after my next testing
2. I actually ran into this problem back in May when I first got the Titan. I talked to Tim and he got e3d to send me a new gear since mine was bad back then.
3. I've kinda been avoiding this just because of how much of major pain I remember adding the original spacers on back there. But I'll consider it if I still have heating issues.
4. It is a e3d that I got back when they first released. However a few months ago I noticed the fan was not performing as well as it should. So just yanked the shroud off and took the shroud off of the e3d v6 lite that I had. So that is why it is orange, it's from the lite model. I was too lazy to just swap out the fans and just swapped the entire shroud.

[Soynuts]

The wiring seems to have been the issue. It wasn't getting proper consistent current.

[geneb]

It wasn't a current problem, it was a connectivity problem. If you only energize one coil, it's going to just sit there and twitch.

g.

[Soynuts]

Spoke a bit too soon. Fixed the connectivity issue but it's back to skipping after 20 minutes of printing, so probably still a heating issue. So gonna try taking out the board and adding more spacers to see if that helps. Not sure why I'm suddenly running into this problem after 2.5 years of no major issues.

[Soynuts]

An update on this. I had been too busy the last couple of weeks to sit down with it.

The problem ended up being the e0 driver being dead/dying. I swapped pin values for e0 and e1 in the pins.h file, recompiled the firmware, and swapped the motor from e0 to e1. It's now extruding happily and I haven't run into any problems yet. I did add more spacers behind the rambo board (up to 0.75 inches of space) and stuck a small blower fan behind it, so hopefully the e1 driver won't burn out like the e0 one did.

[Eaglezsoar]

I am glad that you got it fixed, good troubleshooting and great firmware knowledge!