Hypertherm 45XP and piercing/cutting 5/8" plate

[bbaley]

Hey all,
According to the Hypertherm cut charts, 5/8" is recommended for edge starts.
But I am curious if anyone has had success with pierces and what settings.

I am trying to cut 3/4" holes to avoid drilling (non critical hole dimensions)

The hole cuts are “ok” at 12ipm and 1.75 pierce delay, however I am getting dross on the topside, which has caused the tip to hit the dross, etc.

Currently only tried with THC as I was hoping would detect/adjust torch height so no crash into dross, etc.

I haven’t spent much time trying to cut much over 3/8" (which works great, no issues), so hoping someone can point me in right directions to try as I do not have a lot of extra stock to play with and waste on experiments that are not worthwhile.

I know I am probably pushing the envelope, as indicated by the cut charts…

Cheers and thanks !

[Phillipw]

I would say it is doable. You may want to go through and pierce each hole then clean off the slag then run the program.

[bbaley]

@Phillipw - how would I do that? just a separate program to run first for pierces ? never done that before

[bbaley]

I thought about drilling 1/8" holes - to assist pierce but save me drilling those big holes

[Phillipw]

find on the visualizer the start for each pierce point do a start from here then pause it after the pierce then choose your next pierce point.

you could also use old consumables to pierce then use good ones to cut.

[brownfox]

I would do this.

I use sheetcam so I’ll explain it according to sheetcam.

I’d modify the design file to have a 1/4 inch hole centered inside the 3/4.

Make the 1/4 inch holes the first operation, and the 3/4 separate. After the 1/4 holes cut, pause the clean the spatter and resume.

Make sure the 3/4 inch holes are set to start from the middle with the lead in. That way it will simulate an edge start.

[ChelanJim]

If you are using Fusion for CAM you might look at trying these settings:
.

I have been pretty successful with this method. Just keep changing your lead-in radius with a micro lead-in until it hits approximately the center. If Fusion hangs while doing it, change the sweep angle to 179 degrees. It seems to be a bit of a fluke with the difference between 180 and 179.

Cutting from the Center of a Hole: Fusion 360

I went through a few of my designs with lots of holes and used your method with the 180 degree sweep setting. It works pretty good. I am not using any calculations. . . just trial and error with numbers. I have had several that simply caused fusion to hang. I finally found that I could sneak up on the 180 by using 179 and it would work but if I used 180, no luck. Thanks again for figuring this out and sharing for those of us with Fusion 360 CAM issues. For those who knock Fusion 360, I underst…

But, I think @brownfox idea is what you need to get to. This might help you do the 1/4" hole in the center, then clean the dross and run the tool path with a start in the center a second time with this type of configuration but going for your 3/4" hole size. Obviously, the pierce delay would need to be short during this second cutting action since there will not be material to cut during the pierce.

[TinWhisperer]

@ChelanJim

If Fusion hangs while doing it, change the sweep angle to 179 degrees. It seems to be a bit of a fluke with the difference between 180 and 179.

I like 170 deg saves the headache

[Phillipw]

Didn’t think about it earlier you can do a wiggle pierce in sheetcam not sure about f360. It is supposed to help pierce thick metal.

[geoffsteppler]

Have you tried weld anti spatter spray? I find it keeps the top dross loose. Most of it blows away. Or a light side tap breaks it free. I spray the torch shield as well. If I see a glob hanging on the shield, a light tap with a blade and it’s off. I don’t even stop the cut.

[bbaley]

no I haven’t but I will pick some up and try it !

[bbaley]

thanks everyone for the ideas. I’ll give them a try this weekend!
much appreciated.