What speeds do you use ?

Thank you AxisLab.
If I want to change hobbed bolt I have to ask Robo3D team, or is it something you can find everywhere ?

 

Yes google translate doesn't know "hobbed"
Where did you buy yours ?

 

I suggest that when you order you request that the "hobb" be 15mm from the base of the bolt head. Most sellers will have one or make one with this measurement. That should fit the Robo3D with the one required washer between the bolt head and the bearing. Search the forum for affixing the lock nut in the gear with Locktite or a grubb screw.

 

It is a very easy fix you can do yourself if you order one, I believe there is a video of the task somewhere but I am not quite sure, if I find it after work I will post a link.
I would chance that you may not need a replacement right away, it is possible that yours just has been somewhat clogged by chewing at the filament. You may just try to clean it off first.
Once you see it you will see clearly the little teeth that can clog. Have you noticed any colored dust on the top/back of the print head or behind the machine?

The upgraded bolt is a cheap, easy and recommended upgrade however you should be able to print just fine with the original, I am at least so far. I bought a replacement but haven't even put it in yet. Just don't see the need yet.

 

I was able to get some good prints with the stock setup. I was able to use use the stock bolt but I had to tighten the two screws on the filament latch (I ended up removing the springs entirely and now I am using nuts). If you are getting dusts its because the bolt is scratching and chewing the filament instead of moving it.

 

I believe that they have changed the hobbed bolt over time. So it really depends what one you were shipped. The one that came with my November shipped printer was useless. Besides having no groove the teeth were angled backwards to the direction of rotation so it would always slip.

I also tightened up the springs with a few extra washers (I suggest this). I also use a grooved idler bearing but I'm not sure if it is needed.

I want to be clearer on the use of the Locktite. The locknut can rock back and forth in the gear a bit on each extrude/retract cycle. The High Strength Locktite pins the sides of the nut to the gear to prevent this. It is removable but try not to get it on the threads. Takes 24 hours to dry.

 

Thank you very much for these informations.
I was planning to remove the springs and put 2 shorter screws, I think the springs don't push enough and make the teeth scratch instead of pushing the filament.
I keep the links for a replacement bold.
I'll tell you how it worked.

 

OK it worked
I removed the springs and put shorter screws and 2 pieces to adjust screws lenght, so filament is strongly pressed and pushed in extruder, see picture.

Right now I'm printing Z-axis stabilizers ans spool holder from thingiverse.
Thanks to all of you.

 

Awesome!! Glad your running!! Looks nice and clean too. I was printing with that same color green PLA from Robo3d if thats where you got it and just ran out a few days ago. I will order some more for sure. I was using it with a little higher temperature at 208 and it ran flawless.

 

It's ABS, not PLA, ordered with my Robo3D printer