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Biesse Rover 30 jerky motion on corners7/23
After almost a year of solving ridiculous issues, our Rover 30 is making parts, sort of. Just a bit of background, we have 2 other Biesse centers and 2 Multicams, so needless to say I was surprised at the difficulty this machine has given us.
Anyways, I'm using the XNC post from Enroute that I use on my Rover 322. The issue I'm having is that when the machine arrives at a corner it decelerates to a near stop and accelerates back up to speed in a very jerky motion. This causes the gantry to shudder and make terrible corners. I would expect this if we weren't rolling around the corners,but we are. At every corner the post issues a G4 command and a radius of half the cutter diameter.
The axis move smoothly and the machine doesn't seem strained and only misbehaves on the corners. i don't know why it decelerates so abruptly. Any thoughts would be appreciated.
There are a few reasons this may be happening.
Deceleration and acceleration settings are wrong or have been modified in the machine data.
Another may be mechanical slack in the ball screw and or rack and pinion and or drive system. I've personally seen this on a rover 336. The rack was never lubricated as a result the gears had severe ware.
Call Biesse they have good support.
Why a G4 command. Isn't that a dwell command? Why would the post be inserting a dwell command there.
I'd try editing the code to remove the G4 and see what happens. If it solves the problem then experiment with some different post processors.
You might consider posting the code you are getting for a corner here on the forum.
G4 and G5 in Biesse controls is arc radius code. G4 on Fanuc is dwell, if you don't know you know.
Ahh....always something new to learn.
On my machine G2 and G3 are the arc radius codes.
Most likely mechanical. Likely you have rack and pinion for both X and Y. Also very likely these two have never been greased. So now you have a pinion gear that has worn. Easy fix, just loosen motor and get pinion gear to seat into rack. Call me if you need to. Over 22 years fixing Rovers.909 606 0140.
Quick update. It appears to be an issue with the post. If I enable "sharp corners" in the post and eliminate the roll around corner code, the machine smoothly decelerates at the corner and the accelerates with the change of direction. The parts come out nicely.
I had a similar issue with Mach3. I tinkered with the accelerations and it improved. I them tried other PPs "with arcs" and that did the trick.