Need better cuts

The size of the hole matters as well as the material. Most of the steel i cut is 0.080" 4130 cromoly and the material i cut most is 0.032" 5052 aluminum, so my settings arent going to help you much. what is going to help you a LOT is to click the FEED OPTIMIZATION box when doing the cutting portion of your post processing and crank amps to 95%-!00% of your consumables rated amperage. Start using the autofill settings and see how it works for you. tweak from there if it is necessary but clicking that button was the single best improvement for small holes and fine detail ive made. it makes me look like i know what im doing and im almost as new as you.

I found some guides online that help a ton. ill see if i can find them and ill post up the links.

What you are missing is regardless of what the metal does the torch needs to stay put.
Now i’m not a plasma cutting guru and i don’t know squat except what i have read and what i have seen this machine burn up in terms of material wasted because it couldn’t maintain my required tolerances.
All i will say is try to cut a 1.5" strip that is 3.5 feet long along the x axis of 0.032" 2024 aluminum sheet with THC on and you will be throwing it in the trashcan because it will not maintain 0.060" external dimensional tolerance. When i find the guide for Nvrsrrnder which is on the hypertherm website i will post the link and you can see it instruct you that THC complicates hole accuracy.
I was throwing a lot of money in the trash. Turned off THC , started using feed optimization in fusion 360 and havent had a problem since. I’m probably wrong. i am a newb since February 22. i’m confident you know more about plasma cutting than i do, but that is what worked for me and turned losses into victories. I had been over complicating everything, now simplicity wins the day.

here is a link to the guide for better quality holes (small holes less than 3/8"diameter).

best of luck.

I think you are right about holes, THC is not helpful for holes I agree but I think you’re throwing the baby out with the bath water. If it works for you keep on doing it. THC is intended to help maintain precise cut height over longer distances. I’m new myself but spend a lot of time doing and researching the topic.

The Firecontrol THC software turns off the THC when the torch speed falls below 85% of the programed feed rate. You can also change that percentage in the THC settings in Firecontrol.

This means that, if you use feed rate optimization to slow down the speed for holes, it will automatically turn off the THC for holes.

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I’m going to have to figure out how to do this… just got a job where I need 42 8" plates with 7 holes each haha! The timing couldn’t be better

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If you are not having problems use it.
but my guy Nvrsrrnder is having problems.
and turning off THC is an option.
Its a very simple option that solved my problems with a single click.
So my comments are to maybe help him with a way to simplify and determine what is and what is not contributing factors to his problems. His problems are somewhat similar to the problems i was having.
So if the baby in the bathwater is a piranha, yeah, you throw that out before you climb into the tub right?

My experience with THC is this:
I am cutting a piece of 0.032" 2024 aluminum sheet.
the piece is an inch and a half height and 32 inches wide with some geometry on the ends.
It is the frame for a cowling hinge on an airplane.
Due to how thin the aluminum is and the bends required the grain of the metal is critical for structural integrity.
When using the THC one side cuts perfectly, but when the other side bows up ( warps ) Pythagorus shows up and reminds me that the distance between a and b on a flat plane is different from where it is when spatially elevated off the work surface and i end up with 2 edges that are not parallel to each other. Maybe one solution is to use tabs to hold everything in place and increase the amount of hours of labor required to finish the part, which will translate to higher prices to the customer. Or i can turn the THC off and make enough parts to keep me in stock for the next 6 years in only 6 minutes.
I bet there is a way to tune it so it will not ruin my parts. I also bet its a lot more work than disabling it (which solves the whole problem in one fell swoop) with the click of a control box. I dont see any babies analogous to my work situation. I suppose if you are trying to cut corrugated tin THC would be a must have and worth tuning to your application. Or if there are radical changes in material thickness, yeah that would be worthwhile. But since i have a reasonably level bed surface and i am cutting a flat piece of metal with a thickness tolerance around 3 thou all THC does for me is allow my workpiece to move around and adversely affect dimensional accuracy. I cannot accept that.

Gotcha, OK!

And the workpiece doesn’t warp without the THC? Or is the torch holding it down when it warps up and hits the nozzle?

You do what works for you, but advising people to turn it off is not the best advice. These people paid extra money to have it and they probably want to learn how to make it work correctly.

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Yes, though not ideal, the torch holds it down and dimensional accuracy is consistent and true.
The man is having problems so one quick way to tell if THC is contributing to your troubles is to turn it off and i don’t believe it is bad advice to point that out. But you’re welcome to troubleshoot with all bells and whistles turned on if you like. Unlike us who are brand new to plasma cutting you have probably forgotten more than we ever knew, and to you its simple as eating with a spoon. For me and probably others making it as simple as possible to rule out contributing factors might actually be more productive than wading through unnecessary levels of complexity. So to identify if THC is contributing to your problems, yes turn it off. Its not hard to turn it back on. And the plasma cutter works perfectly well without it. Who knew?