Plasma Cutter Question (1 Viewer)

D'Animal

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So I got a new Thermal Dynamics Proffesional Cutmaster 39 for my birthday. I have never really used a Plasma Cutter. I think I cut a total of about 10' of new steel my entire life with one.

I bought extra consumables and FC187 at FC Fabrication gave me a crash course on his Thermal Dynamics Proffesional Cutmaster 100.


How do these things work on body panels? My tub is rusty and the more I move it around, the more bondo falls out.

Do I just crank it up and go for it or should I use my air grinder/cut off wheel in the bondo areas?


Thanks
 

Mace

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depends.. I absolutely love my plasma..

If you want a perfectly straight line, then a saw might be a better option if you do not have a steady hand. If you have a nice steady hand.. The plasma will do the job nicely.

BTW, bondo is hard to keep a good arc going through.. Unless it is on the other side of the steel..
 

KLF

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I would try to knock most of it off if you can, mostly because it will stink and smoke like crazy when you burn thru it. They cut really fast thru sheetmetal, so be prepared to move quickly or the cut line will be really spattered and jagged. The other nice thing about the fast cut is the heat won't distort the panel.

Try to put something behind where you're cutting, as the gas will really splatter molten metal on everything behind the cut. It can be a pain to clean up.
 

Awl_TEQ

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Yeah, I would grind off what you can. You don't have to make it perfect but the more rust/bondo/paint the more smoke. You can cut a straight line, depending on the shape of the panel, by using a bit of angle iron for a straight edge clamped in place. Also KLF had it right when suggesting a "spatter catcher" on the other side if you wan't to keep it clean.

Also, a note of caution. Plasma is instant hot. You can't clear the tip while running with a quick rub of the glove like you might with a torch - it will just cut through your glove (and you finger). Stop the arc first. We had a guy in our shop burn his hand pretty bad by a quick rub across his hand. He was wearing the thick welding gloves, not the TIG gloves.
 
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Just crank it up and go for it. You'll have to learn at some point, might as well be now. I love my plasma, a little too much I think. I end up cutting a lot more than I want to just because it's a lot of fun.

I'm just starting my body work, but if you can clamp a straightedge to the cut then it makes a pretty clean cut. For an odd shaped piece where you can't clamp a straightedge, it helps if you can clamp something that runs somewhat parallel to the cut to support your cutting hand as you move. It's better than trying to freehand it. That helps when you're welding too.

The liner will stink and smoke a lot, you might wanna grind it off first. You're gonna have to grind it off anyway before you weld it, so either do it now or later. Oh yeah, you probably know this already, but make sure to have plenty of ventilation. Plasma cutting throws off a lot of metal dust.
 
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D'Animal

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Here is what I'm working on.


"East Coast Mint" 196? FJ45 SWB non-removable top bed.
DSCF4597.JPG
DSCF4599.JPG
DSCF4587.JPG
 

RockDoc

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I think I found the solution to shortening this bed.

Used to run similar for getting rock samples when I worked summers for the provincial survey (diamond blade). Good times....., once we did a favour for the guy across the road, cut up a concrete sidewalk so he could pop the pieces with his bobcat. Forgot to bring the ear protection that time. :doh: Man those things will sing. :hillbilly:
 

D'Animal

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Thanks

I used the gas powered unit for the big stuff and used my air saw to tiddy things up before welding.

The results are in my FJ45 build thread.

Dan I'd reccomend an air saw for sheetmetal. By far the best tool for the job.


You will laugh on how I fill the gaps.
 

D'Animal

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LOL!

We've got a saying at work about gaps. If you can step across it, a good welder can fill it! :hillbilly:


I am becoming a welder, not just the owner of a welder.

Thanks to all for your assistance in my not messing up my new plamsa cutter.
 

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