Powermax45 machine torch not cutting vertical

[mx83turbo]

Guys great forum this is my first post. I'm new to both CNC and plasma cutting.

I've just fired up my PM45 machine torch on my home built CNC. Its 1250mm x 1250mm x 500mm capacity with DMM servos and chinese ballscrews, mach3 and sheetcam. Everything is checked square and running sweet, however the machine torch is producing cuts with a noticable angle in my +X direction. So the results for a circle cut in 8mm plate steel is like i used a cookie cutter and held it on an angle to cut out the circle. The angle is approx 1:8. Any ideas much appreciated.

[jimcolt]

The obvious question....have you squared the torch accurately to the plate? Are you using a Torch height control?

Jim Hypertherm

[mx83turbo]

Yep i've aligned the torch all square, and i'm not running any torch height control. I'm using the pierce height and cutting height as per the operator manual and the cut angle is present for a wide range of traverse speeds. I guess next wknd i'll rotate the torch 180deg in its mount to try and eliminate the torch.

Also i did have an angled spark deflector on the floor 600mm below the torch facing the same direction as my cut angle, could this have influenced the plasma?

[jimcolt]

What is the material type and thickness. Also, can you verify that the cut height and pierce height is correct (measure it after height is set).

If your torch is perpendicular to the plate, angularity that is not uniform (sounds like you have a negative angle on one side of circle and a positive on the other) is normally caused by a damaged nozzle orifice. An orifice can be damaged on the first pierce if the torch is too close to the plate or the pierce delay time is too short. There is a section in the Hypertherm manual that describes how to inspect the consumables.

Jim Colt Hypertherm

[mx83turbo]

I'm cutting 8mm mild steel, and i've been checking the Z height before each cut (because i dont want to crash my new machine). I just rotated the torch 180 deg in its mount and the cut angles rotated with it, indicating the angle is in the torch somewhere rather than the mount. Having a closer look it appears the retaining cap section of my torch is not parallel to the main body which is what i originally squared off. This might account for some of the error.

I've had a close look at the consumables and they look pretty new still, there is however some signs of curved radial arc marks on the inside of the nozzle and on the end of the electrode...is this normal?

[jimcolt]

The swirl marks inside the nozzle are normal. The orifice of the nozzle (refer to your manual) needs to be closely inspected for out of roundness or nicks. This orifice shapes the arc....and even a microscopic nick will cause the sysmptoms you describe. One pierce too close to the plate (refer to pierce height in your manual) can damage a nozzle.

Jim

[mx83turbo]

Jim thanks heaps for your help, I've learnt a lot over the last week. I could easily have damaged a nozzle being a total beginner. I'll re-square the torch, check all pierce settings, install a new nozzle on and get on with making some parts.

[mx83turbo]

Problem solved, it was a damaged nozzle, thanks Jim for pointing me in the right direction.