Different layers not lining up when cut

[adbuch]

I agree with TJ I have attached one image with things that could be changed to help. The torch mount is way to long and the lower part looks like a floating head assembly. If the blue section is repositioned down and the torch holder shortened it may help. The single linear rail that is used on the torch holder may not be steady enough. Her is another view from their YouTube post and the torch holder is positioned much shorter, it may be a newer design.
bad table.JPG
bad table 2.JPG

Tom - I agree! Lots of weight cantilevered out there with not much support. If he can grab the torch with his hand and wiggle it (it has movement) then that could be a problem. You want your torch nice and tight. Also check the entire machine by grabbing the axis and trying to move them by hand with the system powered up. There should be no detectable movement at all.

David

[acourtjester]

Another video with the torch much closer to the linear bearing on the floating head assembly.
This video at about the 17 minute mark shows the guy mounting the torch and it is mounted much shorter on the aluminum flat stock position.

bad table 3.JPG

[@metalman23]

I appreciate the advice and help troubleshooting, TJS is about an hour from me,, I'm in central CT

I can try stiffening up the z carriage, but despite appearances, it's actually pretty sturdy,

Also when I cut out some spiral stair treads earlier in the year, from 1/4" plate, when I nested the file it had some steps left to right, and some layed out front to back, the steps that were left to right (X) were too long, but skinnier

The steps that were layed out front to back (Y) were the correct length, but the width was off.

And these steps were about 30", they were close to 3/8" off, in the X direction. I don't think a little wobble in the z carriage would cause a 3/8" discrepancy,

And that's after configuring the steps per unit successfully several times.

Could it be possible for the Mach 3 program to be malfunctioning? Could the program itself need to be reinstalled? I'm just guessing here.

Or maybe the X axis motor is bad, but that theory doesn't explain the successful configuration, but poor performance while cutting a file.

[@metalman23]

Another video with the torch much closer to the linear bearing on the floating head assembly
bad table 3.JPG

I'll see if I can lower that blue part to stiffen it up. Any wiggle I can eliminate will be beneficial

[@metalman23]

I agree with TJ I have attached one image with things that could be changed to help. The torch mount is way to long and the lower part looks like a floating head assembly. If the blue section is repositioned down and the torch holder shortened it may help. The single linear rail that is used on the torch holder may not be steady enough. Her is another view from their YouTube post and the torch holder is positioned much shorter, it may be a newer design.
bad table.JPG
bad table 2.JPG

Tom - I agree! Lots of weight cantilevered out there with not much support. If he can grab the torch with his hand and wiggle it (it has movement) then that could be a problem. You want your torch nice and tight. Also check the entire machine by grabbing the axis and trying to move them by hand with the system powered up. There should be no detectable movement at all.

David

I can grab the axis and they won't move at all, everything seems quite tight

[adbuch]

I appreciate the advice and help troubleshooting, TJS is about an hour from me,, I'm in central CT

I can try stiffening up the z carriage, but despite appearances, it's actually pretty sturdy,

Also when I cut out some spiral stair treads earlier in the year, from 1/4" plate, when I nested the file it had some steps left to right, and some layed out front to back, the steps that were left to right (X) were too long, but skinnier

The steps that were layed out front to back (Y) were the correct length, but the width was off.

And these steps were about 30", they were close to 3/8" off, in the X direction. I don't think a little wobble in the z carriage would cause a 3/8" discrepancy,

And that's after configuring the steps per unit successfully several times.

Could it be possible for the Mach 3 program to be malfunctioning? Could the program itself need to be reinstalled? I'm just guessing here.

Or maybe the X axis motor is bad, but that theory doesn't explain the successful configuration, but poor performance while cutting a file.

It is possible that you have a bad x axis stepper motor or stepper motor drive. If you had the same stepper motors on the y axis and x axis, you could try swapping out the motors and/or drives to see if the problem follows the motor/drive. If your system has 2 stepper motors to drive the y axis (gantry) then this may not be possible.

If it was off 3/8" in the x-axis previously, then I would try doing the test I previously described - but maybe move it a greater distance - say 30.000" in the plus direction and then 30.000" in the minus direction. You could just fasten a pointer to the torch (piece of welding rod with the tip ground on one end as a pointer). Make a mark on the material where it is starting from - then in Mach3 command it to move +30.000" and make another mark where it ends up. Then command it to move -30.000" and see if it ends up at your original mark. You could repeat this several times to see if it gets progressively worse as it is moved back and forth.

Also use a tape measure or rule to measure the distance between the two marks to see how close it is to 30". If everything is working correctly, then it should always return to your original starting mark to within 0.005" less - depending on any actual system backlash.

Another option might be to hire TJ to make the drive to your location to help you troubleshoot this.

David

[adbuch]

Also - how long have you had this table? Assuming you purchased it brand new from Premier Plasma, how long is their warranty period. Have you ever been able to contact their customer support to discuss this? If it is still under warranty and you have defective parts that can be shown to be defective, then Premier Plasma should at least send you a replacement motor and/or stepper motor drive. Do they sell individual replacement parts for their tables?

David

[adbuch]

The Mach3 manual explains how to use the MDI command to manually execute a single line of g-code to move your machine. For example, in MDI mode - type F10, G1 X24.000 and hit enter. This will set the feed rate to 10 ipm and move in the +X direction from your current position a distance of 24.000".
Once you have reached your new position, you could type G1, X-24.000 and hit enter to move from your current position in the -X direction back to your original starting position.

With your pointer attached to the torch and a the initial position marked on the material, executing the first MDI move above should move your pointer by exactly 24.000". After the first move, use a tape measure or rule to measure how far it actually moved. If it does not measure to the 24" you programmed, then either your turns ratio is off and needs to be calibrated, you have a problem with your stepper motor or stepper motor drive, or you have mechanical slippage in your axis drive system.

David

https://www.machsupport.com/wp-content/ ... Config.pdf

Mach3 MDI manual.jpg

[acourtjester]

I agree with David's statements and would add there are some contributing facts. 1 the length of the Aluminum bar the torch is mounted to is way to long. 2 Also the Floating head assembly should have a second linear block to make it less likely to flex in the top to bottom area. 3 The fact of using a hand held torch puts all the weight down low and this will also add to the flexing action of the torch tip. The torch cable adds to this action too.
This video explains what I think is what one of your problems is. Grab the torch tip and try to move it from side to side, it should not move any, with power to the motors on.
You statement about the size and shape being off to me is a clear calibration error. I sorry if you don't agree but that's my thoughts. Mach 3 has a great procedure to do the axis calibrations. Repeat it and each time increase the length you use for the calibration to almost full axis travel.

[acourtjester]

To verify you table is calibrated and tracks square you can use the old 3, 4, 5, method. Or making a square on a surface and measuring from opposite corners to check the exact distance to be equal.

345 methhod.JPG

[TJS]

I used the 3 4 5 when I had a full 4 x 8 sheet of 10ga. I want to do it again after a clean out.
Here is the vid I used for reference.

[acourtjester]

When using Mach 3 I use this procedure, for others I use a different nethod.

[TJS]

That is a really nice way to do that Tom. Very easy.