EZ Router Binding

I just recently purchased a used EZ router. The previous owners had been using it for plasma, but with help from a friend we got it switched back over to routing. We had to do a few tweaks - the main one was the machine was running a bit out of square. We added another homing switch, which gets triggered by a bolt we can adjust in or out, and set Mach to home/square itself. Much better.

Chased out a few gremlins, noise issues, added some E-stops, etc. and have been cutting fairly well - 350 ipm, 2 passes to cut through 3/4 MDF with a whiteside single flute compression bit. Getting fairly good results, although I think V-carve doesn't like some of the arcs I have drawn up.

But, I am getting a binding on the homing end of the router at anything above 400 ipm. At 400 I haven't got it to bind (knock on wood). At 500 ipm it binds occaisionally. Anything higher and it binds quite often or every time it gets near the end of the table. It seems to bind on what I believe is the Y-motor, not the A motor. I have lubed, felt for galling or anything on the V-rails, cleaned the rack and adjusted the bearings, but no luck yet. Anyone have any suggestions? I'd love to get this thing rapiding at 800 or 1000 ipm (should be doable, correct?), and I'd like to be able to cut at 400 ipm or higher... or basically as high as the machine can go. Anyone know what that is?


Thanks in advance,

Will

Check to make sure the home switch is prior to the physical stop of the axis. If you are going fast in a homing routine and it sees the switch the momentum of the machine will travel past the point the switch fires and might jam into the stop causing some binding. The other thing to check is to make sure that both rails are running truly parallel to each other and ensure they don't get closer or farther apart right near the end of travel. You can rig up a board with a dial indicator attached at the end and support it and slowly move the axis back and forth and if the axis is truly parallel the dial indicator should read the same thing from one end to the other.

Russ

Hmm. The location of the limits/hard stops seems fine.

I tried loosening the bolts holding the rails on, drove the gantry to the 'good' end, and tightened the bolts, then moved it down to the next set, and tightened those, etc. all the way to the end. Just eyeballing with a tape measure they seem parallel. I'll try with the dial indicator later when I have time. But in any case, my quick fix didn't work - still binds on that end only at anything over 400 ipm. I don't think it's a particular spot on the rack - I can't see anything, and it seems to happen at different spots dependent on velocity and acceleration. It will bind on that end, but if you have it slower, it makes it a bit further before it binds. Anything else to check before I bust out the dial indicator?

Are you using a ballscrew or do you have cog rails? If it is a ballscrew check for any binding there. Maybe disconnect the axis and move it in the area of binding make sure it feels very smooth.

Russ