Compensating For Angled Cut

Hello Everyone,
I would like to have the ability to create an angled/beveled cut. I can simply redesign the way the z-axis attaches to allow degrees of angling. Though I'm curious how I would go about compensating for the possible voltage difference, the distance offset due to said angle, and the z-axis limit in terms of configuring with Linuxcnc. There may be even other things I'm not considering as well.

Hey Tommy!

Thank you!

I will be using a Hypertherm 85xp so the cut width capacity is around 3/4”… sort of. The angled cut thickness will have to be tested and tried. I’ll see if there are alternative tips for angled cutting and pressure recommendations. Good point!

any thoughts on programming the machine to know the offset? Say I angle it 45 degrees, when it plunged down it will have to plunge further than it normally expected to detect the material. Then once it is ready to start cutting the torch top will be whatever distance offset from the machines predicted cutting point, since it’s set to one side at an angle. Can I set specific offsets for the machine, then assign those offsets names like “15 degrees angle”? 

Is this just to cut ”strips” from the edge of the plate or is this to do actual bevel contours?

Do note that you can adjust the cut height during cutting in the Z direction, the torch needs to adjust perpendicular to the torch. So you would tilt the whole lifter instead of just the torch if you want to have example arc voltage control during cutting.

Bevel cutting is always, excluding edge start, pierced straight and after you are through the material, you tilt the torch. This is because the plate will deflect the arc and make it much harder to pierce. The bigger the angle, the harder it will be to pierce.
The torches and consumables are not different from the normal ones from a pierce point of view. They are “pointier” so that you get the proper cut height when the torch is tilted.
Powermax will not have any bevel consumables or charts to bevel. I think maxpro nowadays has bevel consumables and the all the rest is highdef stuff.

If you just cut strips and you can start from the edge just go for it. Then either tilt the whole lifter or cut without arc voltage control and level the plate “manually”.

Hello RDA,

This would most likely be only for edge cuts that can start from off the material. Though I would like to also be able to have it used for designs. I could simply ensure I have a start cut first that comes in straight then I can do the actual design coming into that. I didn’t think of this, thank you!

when you say till the whole lifter do you mean the entire z-axis? Or just the torch? I plan on having the torch attached to a circular break away plate that is fixed with pins. Then it will marry with a circular dial of sorts with holes every 15 degrees. Therefore you will be able to manually remove the torch breakaway and lock it into another pin set.

i can disable the THC for this feature if that would be easier.

If you have to be able to adjust the height during cutting, you can’t just move the Z axis up and down if the torch is tilted. If you have a laser pointer, put it on an angle and then move it up and down. You will see the dot moving left and right. If you want to be able to adjust the height during cutting you need to move the torch perpendicular to the plate. This would mean tilting the whole Z-axis.
I would say, start with disabling the THC and starting from the edge. When that’s not enough anymore, then you can try to figure out the next steps.

I see what you’re saying. That is a predicament, though I can figure that out later alike you mentioned. It may be solvable with the same me mechanism as the dial and some more thought as well. Though for now I’ll disable the THC.

how about the offset issue? Rotating the torch will offset the predicted cut point from the actual cut point. Can I program that out?

That marking thing seems pretty nice, you think a Hypertherm 85 can do that? I would love to have a fully rotating robotic arm for the torch. Though for now I'm going to stick with a fixed manual angle for the torch.

Is there something I can do in Linuxcnc to have it "automatically" compensate for the angled offset?