Jerky Y axis

[beamsjr]

I have just finished cutting out and assembling the Joe's 2006 router. The Y axis seems to jerk a bit when moving. When I push back and forth I can not feel any looseness. I am just curious what might cause this? I was thinking maybe a bad bearing... Also should I have a bearing on the lead screw at the back of the gantry?

Also what kind of speed should I be getting? Anything over about 30-40 IPM and the motors stall. I am using the hobbycnc pro board and the 305 motors. Does this sound about right?

Thanks, Joe

[joecnc2006]

Originally Posted by beamsjr I have just finished cutting out and assembling the Joe's 2006 router. The Y axis seems to jerk a bit when moving. When I push back and forth I can not feel any looseness. I am just curious what might cause this? I was thinking maybe a bad bearing... Also should I have a bearing on the lead screw at the back of the gantry? Also what kind of speed should I be getting? Anything over about 30-40 IPM and the motors stall. I am using the hobbycnc pro board and the 305 motors. Does this sound about right? Thanks, Joe

you should easily be getting 80-100ipm, not sure what you mean by a bearing at the back of the gantry can you take a picture of the area. Also use white lithium grease on the leadscrews to ensure smooth and easy turning of the leadscrew.

[service_bb]

Does it run on linear guides or box ways? If it has ways, check gib adjustment. Check backlash for the lead screw.

[beamsjr]

Ok, I have taken it apart and checked the bearings. I had 3 that were really hard to turn and I replaced them. I installed an anti-backlash nut at the rear of the gantry, where the leadscrew exits the gantry on the Y axis. I am getting about 60 ipm now. The hopping still exists, but very slight.

When the gantry gets close to the ends of the Y axis (mostly the back end, about the last 20" about 12 in the front) it stalls out. I have checked the lead screw to make sure it wasn't bending and binding it up. I will take some video and post it up tonight.

I will also get some white grease on there!

Thanks, Joe

[beamsjr]

Here is a video of a test cut at 60 ipm I did earlier today. It came out ok, some jaggy edges I am sure is from the hopping.

YouTube- Test cut on my homemade CNC Machine

YouTube- Test cut on my homemade CNC Machine

[beamsjr]

I have got the machine running pretty good now, I am having a really hard time getting it to cut square though. Its off by about 1/4 inch over 30 inches. I used a square to check the table inside of the cross braces and they seem square. The gantry seems to be square, when I run it up to the front of the table the gantry sides are the same distance from the end. Any ideas on what I should check next would be appreciated!

Thanks, Joe

[beamsjr]

I was playing with the gib adjustment and I think that is going to fix my problem. Hopefully I will have some time to play with it in the morning.

Thanks, Joe