plasma cutting problems

[lamicron]

I am using a new Hypertherm 1650 in my cnc table, it is cutting half of the part ok,(circle, square, any) and the last of the cut is making some angle . We have good air pressure(big compresor) The dross is to hard to take off, we have tried speeding the machine, we are cutting 3/8" at 1000-1200mm/. also used different tips and noozles . Anyone with this problem ?
Thanks
Luis

[Edwardo]

I would check to make sure the torch is as close to vertical as possible, then check the air again, you said you have good pressure but is the air dry? Check air filters to make sure they are not restricting the air flow because you can have good air pressure but poor air flow.

EDD

[jimcolt]

When you have a varying angle....it is usually one of two things.

1. Torch not squared to the plate on both x and y diections.

2. Nozzle or shield is damaged. One pierce done too close to the plate will cause damage to the nozzle or shield orifice...that will cause varying cut angles. Inspect the nozzle and shield orifice with a magnifier or jewelers eye loupe....if there are any nicks, notches, or out of roundness noticed...then this is the problem. The nozzle orifice shapes the arc, the shield orifice helps to increase energy density (only on Hypertherm units)....

Piercing plate is critical....the pierce height should be set at 1-1/2 to 2 times the cutting height...and a pierce delay time should be programmed to allow the pierce to fully penetrate the material before any torch motion occurs.

For cut speeds...refer to the Hypertherm operators manual....use the optimum speeds for minuimum dross and acceptable angularity. If you cut slower expect dross...if you cut faster, dross will be minimized and angularity will be worse.....but should be uniform around the cut. If torch to work distance varies....angularity will vary as well.

Jim Colt Hypertherm

[lamicron]

I found water in the air, and also will check on the heigth and speed , Thanks for hrlp
Luis

[ajclay]

The torch has to be square in all directions. I made a tool to replace the torch tip that would hang down a few inches so a small machinest square could be used. Even then if the plate is warped you won't be able to get the same cut edge on all sides. Or if the plate warps during a job it will vary the cut... It's a lot more demanding than what most think.

If torch height changes, the angle won't be the same on a sides. It's never just one thing or one problem.

The torch tip has to be perfect too if you are trying to keep taper to a minimum.

Aj

[Jankeen Bablees]

Hi:
i use hypetherm software for my machine,
when we have 5 webs and we want cutting them on one plate, when we arrive to final piece we face problem about it( you can check attached file to understand the problem )

thanks

[ajclay]

Hi:
i use hypetherm software for my machine,
when we have 5 webs and we want cutting them on one plate, when we arrive to final piece we face problem about it( you can check attached file to understand the problem )

thanks

I've never seen Hypertherm Software, but your problems are in the machine setup. The steps per inch or MM must not be correct and the table squareness must be off. The further the torch gets away from the origin the worse things get.

You'll need a good pointer connected to the torch and check travel on a long scale or ruler of some type. Or with a dial indicator and check the travel over a couple of inches. Now you can adjust the steps per inch by trial and error if you don't know the gear reduction of motors and encoder steps.

As for squareness put a full sheet of metal on the machine and check the four corners. Of course it will only be as good as the plate. It may be as simple as adjusting the "homing" stops.

The software problem must be a "soft limit" or the software doesn't know the size of your cutting area.

You'll need a manual on the software or go to "help" in the software to figure it out... I"m sure "Jim Colt" can get you straight too....

Hope I gave you an idea..

aj