Broken Motor Mount

[jimc]

funny, now that you mention it, even though my motor mount didnt break it is a reprint i believe i got from the makergear github and i just checked and it doesnt have the hole....strange. i reprinted all the plastic parts in 80-100% infill so they are more rigid and strong.

[Tim]

Can you post a quick link to that version? Because I got the files from the github site recently, and I have the original motor mount and the "r2" motor mount, and both of them have the hole.

I printed with 60% infill, and it seems solid enough, except that I was printing a new motor mount while using a cracked motor mount that was rapidly losing its grip, so it was an iffy job and I need to do it again.

In addition to losing the hole, I would like to see three tabs in the front to fit the depressions in the front surface of the motor. That would prevent any unwanted shifting of the motor, even if the mount cracked. I'll have a go at a redesign myself, if nobody else gets to it first.

[jimc]

yeah here it is tim. if the one you got from github has the hole then i have no idea where my model came from. i downloaded all the m2 stl files back when i first got my machine so god only knows.

[Tim]

Thanks for the link. In some ways it seems like some intermediate stage between rev 1 and rev 2, except for the disappearing hole trick. At any rate, it's what I was looking for and saves me the trouble of making the hole disappear myself. I'll call it rev 3. I will still add the tabs to prevent rotational slipping and repost it as rev 4.

[Capt. John]

PLA mount I made, not recommended ...is still working after loosening up twice.
Guess, it stretched as far as it could and then stabilized.

Haven't swapped out the PLA mount yet. Mostly, because I don't want to reset the head space
on the hot end distance to the glass build table.

MG came thru with a warranty replacement and have printed out 2 more spare replacements in ABS.

Have the 2 head version on order, so what I have now will be replaced anyways.

[hungrygeneralist]

Hey guys, just wanted to pitch in that I had this problem too on two out of three Makergears (each about 6 months old.) All three are in boxes to keep temperature warm/stable. I think a hot environment probably shortens the life of this part.

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Motor Mount Cracks

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[jsc]

A friend just had his motor mount crack. He reworked the part from github to his liking, to thicken it up and remove the weakening hole:
http://www.thingiverse.com/thing:432956

[jimc]

nice jin. that looks good. ill have to print one of those out.

[jsc]

Some of you may also be interested in Eric's rework of rsilvers' filament path: http://www.thingiverse.com/thing:433292
Mostly streamlining of fillets and selective strengthening. Looks like the top nut channel was rotated to be flat, and the feed cone angle increased to 30 degrees (from 20). Also a portion of the wall by the shoulder bearing screw nut was debossed to clear the barrel when the pressure adjustment screw is tightened.

All of this is only of academic interest for me, as I have moved to the v4 extruder and I think the filament paths are not the same, but Eric's modifications look like useful incremental improvements.

[jdacal]

A friend just had his motor mount crack. He reworked the part from github to his liking, to thicken it up and remove the weakening hole:
http://www.thingiverse.com/thing:432956

I made these but had some issues after installing it. The Z knob (the original one anyway kind of wobbles a little), on mine it was hitting up against the front left edge of the mount (just barely but enough to cause the over current on the Z motor to shut down and do all kinds of weird up down gyrations). It required a little bit of filing of the mount to eliminate the problem.

The other issue I had was that the holes for the adjustment screws are not spaced the same as the original. So my dial caliper mount that mounts there couldn't be used anymore. It is definitely a hefty motor mount, would love to keep using it but I don't want to give up my favorite dial caliper mount. Or I may have to make my own when I get a chance.