Hey folks, I have an ongoing chain skipping problem. Mainly near the top of the sheet. Its very consistent, if I loop back to the same few lines of gcode it will happen in the same spot everytime. Im sure alot of my problems will be solved by modifying my frame (extending top beam outwards & making a better chain guide) and upgrading to v 1.00 of software and firmware. I would like to finish my current cut project before doing more mods/updates.
I added a counterweight to the chain slack sprocket which I think causes more tension on the motor sprocket, and that has resolved 80% of my chain skipping, I can loop back to the same gcode spots and it will no longer skip. Has anyone experimented with this before? I havenāt been able to find anything in the forum.
Sorry for the trouble! I did play around with a counter weights system early on and it worked well. It got removed from the design because it added cost and complexity, but it always worked well. I found that to keep the chain aligned with the sprocket (because the sprocket is tilted and the weight wants to hang straight up and down) I had to give the weight a guide so that it would move parallel to the sheet instead of vertically. Overall I think it is a great solution!
Hey Bar, thanks for the info. I will set something up like that when I do my next round of mods! I may cut a pvc pipe length-wize to crate a travel channel/gutter.
It might not be suitable based on your frame design, but Iāve been successful in preventing any chain jump using the kit-included materials by mounting the motors and chain guide in the manner seen in this link:
The āchain guideā is just loose enough to allow the plastic (which i trimmed to length) to spin freely. The angle maintained by the chain to the sprocket is tight enough to force the chain onto the sprocket at no higher than 225 degrees (ie: SXSW, or ~7 oāclock). it acts like a chain tensioner andalignment guide immediately prior to the sprocket.
is it skipping as the sled is moving towards the motor or away from the motor?
if itās skipping as it moves towards the motor, you donāt have the chain
parallel to the workpiece, move the motors in or out to make them parallel.
If itās skipping as it moves away from the motor, look at the plywood chain
guide that was posted recently, that keeps the chain wrapped around the sprocket
and keeps gravity from pulling it too far back
i was planning to put a counterweight on mine too instead of the stretchy string, just makes sense to keep the tension equal at all times, i thought to just let a piece of rope take the path of the stretchy string now, and add a pulley at the top so the weight can freefall, that way you donāt need to guide the weights, and the chain stays alligned with the motor.
Is anyone else having an issue with the chain continually wrapping around the sprocket on the actual motor? Iām finding that for some reason my chain isnāt loosening up from the sprocket, which causes two issues:
sometimes its stuck on the sprocket for just a little while, which causes it to pull up the router passed itās desired cut, and then the weight of the router will pull the chain from the sprocket, causing it to sink back into where its supposed to be
sometimes it gets stuck to the point where the chain will continually wrap around the motor sprocket, which can lead to damaging the machine.
Iām think I need some type of guide for the chain after the motor sprocket to keep this from happening, but wanted to see if anyone else had to deal with this?
The classic reason for that to happen is if the chain is not feeding directly in line with the sprocket, does it look like the plane of the sprockets is in line with where the chain is feeding onto the sprocket?
I think it looks pretty in line, but Iāll move it around a bit and see if that solves it. I think this plane keeps based on how Iām leaning the Maslow with the temp frame, since the legs are just the 2x4ās with the pulley, so Iām thinking that the contact of this bottom piece with the ground might have shift. Iāll double check to see if moving it fixed the problem
@bar I tried leveling the plane of the sprockets and Iām pretty sure itās pretty in line. However, still seeing the issue =/ i took a video to show an example of what Iām seeing
Just an FYI for everyone on this thread. In the ānew stock frameā thread, it looks like we are going to end up with the chain moving horizontally across the top bar. That will go a long way towards eliminating this problem
