bigger extruder motor

[Carlito 0]

hey 🙂 Was wondering, my extruders motors keep dying on my UM2+ after 6 months, happened to me 3 times already in 1.5 years... I switched to the bondtech extruder, but it apparently requires more torque... so the question is, how fat of a motor can I install on it ? like, how much power can the motherboard spare for the extruder motor ? Because I'm really tired of printing at 30mm/s and still getting under extrusion with PLA because of a flipping motor  😕  

 

Thanks ^^ 

 

 

[conny_g 251]

Never heard of extruder motors dying. I bet the root cause is somewhere else.

Worn bowden tube, bad / jammed nozzle, bad part in the print head. Or simply too much motor current so it overheats, ...

[Carlito 0]

Hey, well effectively, wasn't the extruder motor this time... should of double checked before 😕 So the problem is the gear on the extruder motor, the little one that drive the bigger one on the extruder itself, that is becomming rounded on the inside and slips on the axis... Do you know where I could find one ? Can't seem to find some on the internet ! 

 

Thanks 🙂 

[conny_g 251]

You mean within the Bondtech extruder? Check with them if they have a replacement part for that.

I think to remember they have a 3d model of their housing, then it would be possible to reprint it.
But I would assume the resin 3d print is sturdier than a FDM print.

 

And still I think that there is too much force on the extruder for some reason.
 

[Smithy 1,146]

I also think that you have somewhere a problem, and this is not the extruder. So check carefully the advice from conny_g, otherwise, it will not help if you replace the gear, it will again wear out.

[Carlito 0]

Hello, 

Checked again, the extruder turns freely, the filament can run through no problems... And after taking a closer look at the gear, it is definetly the problem, when I put it on the motor and make the motor turn, I can hold the gear, without applying much force at all, and the motor still spins ! It just doesn't hold anymore... So there is to much force on the reducting gear, not the extruder, so strange ! 

 

And just to be shure of what gear we are talking about, I did a little sketch, sorry for my terrible paint skills :') 

 

Thanks a lot ! 

[Smithy 1,146]

If the gear has a normal round hole without a flat part, then you have to position the set screw to this flat part. When tightened, the screw prevents the gear from spinning on the axis. 

[fbrc8-erin 302]

2 hours ago, Smithy said:

If the gear has a normal round hole without a flat part, then you have to position the set screw to this flat part. When tightened, the screw prevents the gear from spinning on the axis. 

 

The geared motors are all press fit. The knurled ones on the UM2 had set screws, but the plastic gears are press fit. 

@Carlito are you putting a lot of grease on the gears? Installation instructions on the upgrade kit call for a little grease, but it should really only be a very little amount. I've seen a few slipped gears, but it shouldn't be occurring at the rate you're reporting. I would check into the other areas conny_g and Smithy mentioned. Something is making it work too hard.