Beveled cut on thicker material

I’m about 2 weeks since delivery now and slowly getting the hang of everything. I designed and cut this simple bracket to use on my welding cart to bolt casters to. Top of the cuts looks pretty good, bottom is all twisted and beveled. I understand why; the plasma is basically drug behind the cut and it’s getting left behind at the turns. But i don’t know what to adjust. Is it simply feed rate? Or a combination of things? Consumable issue? I know there is a lot of trial and error but i hate just shooting in the dark.

1/8" cold rolled
40ipm
28amps
.125 stand off
60psi

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First thing I would do is reduce your stand off. I don’t know what plasma your using but my Hypertherm chart only suggest .060 cut height which is the little shim. If that also doesn’t work try reducing your feed rate. Also 60 PSI seems low for your pressure, but you plasma cutter might suggest different.

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I’ve got 2 more to cut, I’ll try the smaller shim on one and the slower feed rate on the other i guess.

I agree. That’s a huge torch height for cutting. (Okay for piercing.)

I’d also go for some more power & higher speeds. Like 35 or 40A and 60 or 65 ipm (for the Razorweld - I don’t recall what I did for the Hypertherm but it would have been their recommended settings).

And 75psi at the plasma box (not the tank - you lose a fair amount of pressure in a 50ft hose).

I tried switching to the .0625 shim and put in a new nozzle. It looked better but still an obvious bevel. Next i turned up the air to 72 at the box and it screwed everything up and wouldn’t even cut all the way through. Tomorrow I’ll try 35 or 40amps and if there’s still no improvement I’ll drop the feed rate. It just doesnt seem like 1/8" mild steel should need such low feed rates.

Luckily for me these brackets are crude and i could still use them with some flaws Haha.

That’s what I think the problem is - all of my cuts on 1/8" were in the 35-40A range.

@jamesdhatch Welp, i tried everything the same but bumped up to 40amps and literally no change. Then went down to 25ipm and then 15ipm. No change. Then i tried reversing the direction, clockwise and counter clockwise. No change. All of these change just made the dross really bad but the bevel is almost identical on all of the cuts. At 15ipm the cut started looking terrible.

The only thing left to change that i don’t have on hand is the electrode but i don’t think that would have an effect on bevel.

Can you post a pic of your electrode? If it’s worn it will affect the arc size and stability.

Also are you sure the torch is vertical to the material? It can be easy to let it tilt in the holder.

The torch is level to the eye. That’s something i checked early on.

I went to take a picture of the electrode and it’s toast. It was beginning to pit last time i looked at it and now it’s way past its life. I have more in the mail being delivered today, we’ll see if that makes a difference.

Thanks for your help James

Electrode it was. Even when it still looked ok it was cutting like trash.

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Awesome you got results, nice opener too! Post up that file if you’d share, I like it!

I uploaded it to FireShare today. Hopefully it works for you.