Cut over a slot or hole

[Paint Chip]

If you have the setting for interrupted cutting (for doing things like expanded metal) on your Hypertherem then you can go over slots and it should keep the arc going. It's on a settings selector knob on the front of the machine (at least it is on my PM85).

[tcaudle]

Also...THC has to be off. Running over a void or prior cut will cause major issues with the THC engaged. The best advice is: Don't do artwork where objects cross.

[Simko]

If cutting over a previous cut is such a bad thing, then how is it that it works fine with looped corners?

flange.gif (4.62 KiB) Viewed 1102 times

flange.gif (4.62 KiB) Viewed 1102 times

[Largemouthlou]

The kerf line is small enough and torch moving fast enough that it don't skip a beat..

[motoguy]

The kerf line is small enough and torch moving fast enough that it don't skip a beat..

That's a function of your cut speed, and THC sensitivity. Fast cutting with high THC sensitivity, you should be fine. Slow cutting (thicker material) with fast THC setting, it'll probably crash (though that's a combo you shouldn't have, anyway).

[FazQuaz]

I cut over existing cuts all the time and this is how I do it.
-In sheetcam highlight the operation you want to do this with.
-go to Mode, edit action points. Move to the location on the drawing you want to go over an existing line. Boxes will appear that require information. This is what I use:
Length - 1inch Feedrate - 100% Start Code - Code C2 DTHC on End Code - Code C1 DTHC off.

You will also need to put a check in the "Disable Hold" so when the arc signal is lost the torch does not just stop.

[motoguy]

I cut over existing cuts all the time and this is how I do it.
-In sheetcam highlight the operation you want to do this with.
-go to Mode, edit action points. Move to the location on the drawing you want to go over an existing line. Boxes will appear that require information. This is what I use:
Length - 1inch Feedrate - 100% Start Code - Code C2 DTHC on End Code - Code C1 DTHC off.

You will also need to put a check in the "Disable Hold" so when the arc signal is lost the torch does not just stop.

I'll be danged. This is good to know! I'll have to give this a shot! I didn't know I could choose -specific- points on the toolpath for actions.

[FazQuaz]

I forgot to mention, that I break up the drawing into lines that are vertical and horizontal and put them on different layers. I cut the vertical lines first (on its own layer) and then cut the horizontal. The horizontal cut (or layer) will be cutting over the vertical layer and will require the instructions I mentioned above. I hope this makes sense!