I did the initial build for this many months ago (6 or more). I got electronics hooked up and successfuly homed the machine, but never got as far as drawing my crown or even mounting my Dewalt.
Then life happened and it sat. I just found time to get working on it again, and the thing is no longer freely moving. When I finished the build, I could grab the Gantry and move it in circles with my hand. It might catch here or there, but mostly with a single hand you could draw circles.
It’s been so long, I can’t remember which bolts did what, how tight my belts were, etc. I went ahead and unwired all the motors so that electrical resistance wasn’t playing a role.
Are there instructions for how to take a few steps backward, loosening some bolts or tightening some bolts/bands to get me back to a freely (manually) moving gantry? I don’t really want to disassemble entirely and start over, but if that’s what needs to be done I’ll do it.
Edit:
I removed one axis from a truck to isolate that truck. I also removed the belt from the motor so that I wasn’t moving the motor during testing. The truck moves completely freely without friction UNTIL it has to start moving belt through the truck. This is where all of my friction is coming from. The rollers inside the truck as the belt enters and exits seems to spin freely by hand, but the belt seems to be rubbing in the channels. There is a video below showing some of what I’m talking about.
This was not the case when I built it, so maybe my ASA plastic absorbed humidity and swelled?
Loosen the screws that go through the trucks, they are clamping them to the rails (not the ones holding the lower bearings, the ones holding the upper bearings).
A little resitance will always be there since the motors are connected already, but not as much as in your video.
Any advice based on the updates? Should I unthread the cables and try to widen the channels with folded sandpaper or something?
I could also reprint those parts. I could also just hook up electronics again and see if the motors can deal with the friction.
Yeah I loosened the screws which didn’t help too much. If you watch the second video, you can see that truck moves very freely when it’s not having to move the belt through the truck. I had to loosen the belts a ton to get it off of the stepper motor, so I had slack belt. The truck moves extremely freely until the belt has to start moving through the channel. Then I’m getting all that friction, so my guess was that every single one of those trucks is not allowing the belt to pass through the channels without binding.
That sounds feasible. Is there any dust/debris in the truck’s channels? Did you put in the belts correctly? It would be very weird if this was the problem. Does it also happen when the belt is not connected to the motors, just pulled through?
I’ll try to do some more disassembly today. Nothing has changed since build date, except it has been sitting in my garage. The thing used to move so freely that you could move the gantry with 1 hand and make circles. Every single axis has this issue. I might also measure the belts with some calipers to see if for some reason my belts have swollen. I purchased the kit including belts from the V1E website, so it’s not like I sourced the cheapest belts I could find.
I appreciate you staying engaged, my wife isn’t interested in talking through troubleshooting steps.
I had something similar happen to my MPCNC. I finally took one of the trucks off and discovered the idler pulleys were loose. The screws had backed out and the pulley was rubbing. Take a look at one of yours and see if this happened to you also.
It may be that I’m dumb and was just lucky 6 months ago. I removed my truck entirely and was having the rubbing issue. I got calipers and measured the belt which was perfectly within tolerances. The channel that the belt goes through was plenty big (I could see light shining through the channel while the belt was in that channel. I took the truck mostly apart and I think I just routed my belts wrong which can be seen in one of the videos, but not in my still photos (sorry about that). I’ve taken a photo from the installation instructions and scribbled in my belt path to demonstrate where I think my problem was coming from. I’ll just change the belt path on all of my trucks and I think it will solve my problem. It made the first truck WAY better.
Yup. Problem solved. Easily moves by hand. Oh man I’m kind of glad I sat on it because if it had been moving well and then developed problems, I’m not sure I would have considered that my build was wrong.
