syilamerica Z backlash

[TOOL MQR]

It's my first time posting a thread so I hope I do this right. I have a syilamerica X3 using MACH3 software. With the backlash compensation turned off I get .006" backlash in Z axis. With it turned on, it moves a quarter inch or so, stops, takes up the backlash, and the continues. In 3D milling this makes a mess. Anyone else having this problem? Any answeres? How long does it normally take to get an answere back from tech support? thanks for any help.

[Crevice Reamer]

Hi TOOL MOR. It's a FINE first post. Welcome to the Zone!

That's a lot of backlash. There may be something loose somewhere. Check everything in your Z axis for tightness. Put a block of wood under the head, lower the head to rest on it, and adjust the Gibb.

Check the coupler grub screws. Make sure the motor is mounted securely to the column plate. Check that all bearing mounts and head screws are tight. Tighten all of the ball nut screws. Make sure the column bolts are tight.

CR.

[TOOL MQR]

Thank you,
That is a good idea about putting the head down on a block of wood to tighten the gib. Is the gas spring the best way to offset the heads wieght? It seems so one sided.

I am running the spindle in manual as the Mach 3 makes it run irradic.

How about backlash compensation? I have a Maxnc that takes up the backlash before a move in the opposite direction.

[Crevice Reamer]

Originally Posted by TOOL MQR Is the gas spring the best way to offset the heads wieght? It seems so one sided.

It IS one sided. The spring may actually twist the head a little. Either use TWO 30 LB GSs one on each side, or counter balance with about 60 pounds.

You know, your gas spring might be too powerful. The head needs some weight on the screw to prevent backlash.

I am running the spindle in manual as the Mach 3 makes it run irradic.

The head should not be erratic. What's going on there? Have you tried adjusting acceleration and velocity?

CR.

[TOOL MQR]

Yes, I have tried to adjust acceleration and velocity. It will run fine for a while and then act like a 4 cylinder engine running on 2 cylinders. i have broken small end mills when the spindle speed drops like that. I have clean power. I run the machine off a voltage/sinewave regulator because we sometimes get low voltage here. It usually runs fine in manual but it has hick-upped a few times.
I am thinking about putting a chip/coolant tray under it for flood coolant and counter wieghting the head at the ball nut but I hate the down time.

I have a maxnc mill I use for cutting EDM electrodes but for metal the X3 is so much better.

[Crevice Reamer]

Check the connections in your Z motor cable. There could be cold/loose joints there that are intermittant.

CR.

[TOOL MQR]

(Still learning how to use this site) I took the Z motors flex coupling off. It had 2 set screws in the top (ball screw) hole. The set screw against the ball screw was not tight. I drilled and tapped the set screw holes to 1/4-20 for a bigger set screw and the backlash went down to .003". Anyone know what the average backlash is on the Syilamerica X3's?
As for Mach3 control software, with the backlash comp. on, should it take up backlash before a change in axis direction?

[Crevice Reamer]

Originally Posted by TOOL MQR As for Mach3 control software, with the backlash comp. on, should it take up backlash before a change in axis direction?

Mach3 simply reverses direction first, then moves enough to take up backlash and compensate before starting new movement. It's just like the old hand-crank method of backing up a ways and then starting forward again while allowing for the movement and backlash. You've got to set it RIGHT though.

CR.

[Crevice Reamer]

Originally Posted by TOOL MQR I drilled and tapped the set screw holes to 1/4-20 for a bigger set screw and the backlash went down to .003".

You might also want to transfer-punch and drill a setscrew-tip sized shallow hole into the ball screw to trap the set screw.

CR.