Old washing machines & tumble dryers metal

[DAPPH]

Still not gone to battle with my new Parkside plasma cutter for various reasons. Have read the handbook several time and so it won't be long till battle commences .

I have been offered an old stainless steel drummed washing machine to cut up if I want it , an old tumble dryer and several 3 yr old 47 kg degassed , steamed out , valves remove propane cylinders . Are these any good for practicing using the cutter ?

Is there anything special I ought to look out for, other than the normal safety rules ?

 

[James1979]

They’ll work

Clean an place for the return (obviously!) and also a place to start. If you take the paint off it’ll be fine.

There is some argument that it’s a better cut on bright steel but for practice/ hacking up stuff I wouldn’t worry. Just needs a good return and if you clean it where you start it’s easier on tip / machine.

Do you have a drag tip for the machine? Makes it easier to maintain cutting distance

The cutting is easy, just getting the knack of speed, not wobbling, etc, but if you’re used to gas it’s no big deal.

Piercing is a bit more of a knack to do neatly. On thin stuff like you describe it’ll be quick. That’s the bit to practice, the pierce. It’s easy to end up with a hole at the start of the cut. 9/10 who cares, but sometimes you need to be neat.

 

[James1979]

Oh. And clean dry air is a must.

Any moisture in the line and it eats tips.

 

[DAPPH]

Thanks very much james ,
Yep there is a clamp on set of roller wheels ,
By what you have just said I might drag the clean dry air in via a dessicant filled home made air filter bowl .. I did wonder how dry it would need to be as the machine is situated out in the fairly dry slightly heated mancupboard . I have drill mounting cup wire wheels and a full 10 mm thick 120 x 900 mm clean welding bench so de-painting both sides of an area to get earth continuity shouldn't be a problem .

 

[James1979]

Some of my filters are home made. Under counter water filter filled with dessicant works well.

As long as you’ve a made a spot for a good return I’d put the clamp on the workpiece rather than the bench.

Better to have a more direct return with plasma.

 

[Morrisman]

As with tig welding, my wobbly hands make neat plasma cutting a pain. The grinding needed to smooth out any freehand work renders the speed of the cut irrelevant.

So, I use a straight edge as a guide when I need to go straight, and whatever is the right radius or curve laying around the workshop for other stuff, and I've even made quick patterns from 1/4" plywood for more complex shapes.

I'd be wary of practising on gas bottles, unless you personally know it's been emptied and cleaned very well.

ETA. Mine is a drag tip, and I give the surface of the work a quick rub with emery if it's a bit rusty or rough, saves the tip snagging and jumping as it's dragged.