Has anyone tried replacing the XY stepper motor with a regular Nema 17 motor?
I was pretty sure I had a bad XY motor so I submitted a support ticket and Bambu support is just a joke right now. It’s been 8 days I haven’t had one response yet. Although I wasn’t sure if the motor was the problem I decided to go ahead and order a new motor anyway. Well, USPS managed to lose it. Sigh…
So today I decided to take the motor off and it’s clear that the motor is the problem. A normal motor should spin pretty easily and this one is very hard to turn. So I took it apart and of course the bearing on the end is not the problem. The bearing nearest the pulley end must be seized or something, but I can’t get to it because Bambu epoxies the pulley on the motor shaft so you can’t get it off. I may be wrong but if I could get that pulley off the shaft and get to the other bearing I might be able to fix it.
As easy as it is to replace most parts on these printers, it’s rather short sighted to me that they would epoxy the pulley on the motor shaft, probably to force us to buy motors from them.
Instead it would be far better to be able to replace those motors and pulleys with typical Nema motors. I even have a pulley modeled that I could put on the shaft of a Nema motor, but I have no idea if they are drop in replacements.
I think the pulley should be no problem but finding the right stepper probably is. Steppers have a few characteristics, that have to match, like inductance or resistance of the windings. For low demanding applications it is probably fine to just slap in any motor. But regarding the high acceleration and speeds of the bambu printers, they have probably carefully selected the motors to match their requirements. They might have ordered a motor tailored to their needs.
I don’t think it is worth the effort to experiment with other motors and would just order the original bambu motors if needed.
Given the fact that I can’t find anyone who has done this, I’m sure you are right. Normally I would certainly agree that it’s not worth the effort. But my frustration right now is that USPS has lost the replacement motor that I ordered (mind you, not from Bambu support, which still hasn’t responded to my support request 9 days later).
I have repeatedly suggested that Bambu needs to offer more and better shipping options which I would be happy to pay for. Radio silence…
An update on the (bad) motor. I took it apart as far as I could and although I couldn’t reach one of the bearings it was clear that the round magnet part of the motor had rubbed against the inside of the motor housing/coils. I kind of scrubbed it out to remove any debris and put a tiny dab of machine oil on the magnet part and when I reassembled the motor it seemed to work OK during calibration and a test print. So fingers crossed that the motor will last a while longer.
I fully agree. having claims against a company that you can’t grab and getting a reply from seems like a gamble let’s you feel really helpless.
I don’t understand why they haven’t ramped up their support capacity in the meantime. The situation is like that for a really long time now.
When disassembling the motor, the bearings looked ok? I would imagine that such a fault is not the root cause but a consequence from another fault.
I could only examine one bearing and it looked fine, and after cleaning and putting back together the motor spun much easier so I assume that the other bearing is ok too.
I’m not sure what could have caused the motor to fail like it did. Perhaps the belt was too tight? When I put everything back together I did try to ease the belt tension off just slightly.
