cutting aluminium /new plasma cutter

[Mikey D]

My new plasma cutter arrived yesterday from weldequip steve
Excellent service as per usuall ,went out of his way to get it dispatched on tue even tho his TNT carrier had already been and gone with the days dispatched items .
how many other vendors would ring the driver to come back ??
top service and much appreciated

Any way onto my question my plasma is rated for 10mm (clean) cut on steel which it does fine
but i had a sheet of 5mm alu and it struggled , more of a severence cut .

so whys that then ? is it just a setting issue ? i used full amperage 40 amps and 5 bar air pressure .


TOday was the first time ive used a plasma cutter , what a great invention tho

cheers mike

 

[Hitch]

Aluminium is strange, never cuts nice even with top end plasmas.

Probably looking at cutting 3mm max with a reasonable cut.

Water jet is one of the best ways to do ally im told....

Wonder if steve can supply DIY versions of them

 

[weldequip]

Any way onto my question my plasma is rated for 10mm (clean) cut on steel which it does fine
but i had a sheet of 5mm alu and it struggled , more of a severence cut .
so whys that then ?

Because aluminium dissipates heat rapidly (that's why it's used as a "heat-sink" in things like Rectifiers)
weldequip

 

[Mikey D]

i knew it would be somthing like that

 

[weldequip]

Shags your torch tips up aswell Mike!
So go slow on the aluminium & try not to be too 'adventurous'... probably around 3mm as Hitch suggested
weldequip

 

[Wozzaaah]

Ah, that's enlightened me too! I tried to cut some 3mm chequerplate with mine and it was a total mess, I gave up and got the jigsaw out instead .
Hey, why do the smileys keep moving around??

 

[snowcat]

The big machines cut small sizes reasonably well, but the bandsaw with a nice chunky blade is better, would much rather guilo straight cuts tho........

I thought it was just me with the smileys, Im strugling to keep up with all the new sections as well

 

[Mikey D]

i bought the machine for cutting steel ,just happened to need a 8x4 sheet of 5mm alu cutting in half .
luckily width ways
I learnt stuff today tho .......
like why heatsinks are made from aluminium

cheers mike

 

[Hitch]

Progressor blades in a decent jiggy for curves works well. Or even straight cuts, then just finish of with a curved tooth file.

 

[piman]

Hello Mikey,

I have used an ordinary portable circular saw with a tungsten tipped blade to cut aluminium sheet (3mm), Leaves a nice clean cut, sprayed it now and again with duck oil.

Alec

 

[hareng]

Scares me that Piman but have had to do similar in the past, bet it was noisy.
Slow speeds with coolant are generally considered best and will depend on the grade of aluminium as well.
Aluminium picks up, once it starts it picks up even more, got to be quick to release the tool when that happens, funny stuff work a lot with it.
Aluminium holds the heat as well, trick is keep it cool as you can or you may lose the tempering and hardness. Will not anodise after as well.
The free cutting stuff is lovely to work with, forget the grade.
Have used variable speed jig saws and repo saws on 3/8"OP chequer plate to good effect.

 

[piman]

Hello Hareng,

No it was not noisy nor as 'vicious' as I thought it would be. Aluminium actually has a very high cutting speed, and as I said I sprayed duck oil as a lubricant and I experienced no picking up. The grade I used was the common or garden grade to build a hopper.

Alec

 

[tigmann]

Plasma cutting of aluminium can be greatly enhanced by the simple
addition of preheat, the more the better!

 

[hareng]

Excellent Alec thats all i wanted to know, next time i will give it a try with the circular saw running fast 3000rpm, course pitch blade than the norm for alum cutting but the feed ultra slow. Reckon worst case the blade will jam if the feed is too fast!

I didnt dismiss this earlier as i have cut sheds and workshops down held together with 6" nails- Easilly slices through the nails at walking speed! Dont do the blade much good though.

 

[Robert]

Hi
A table saw works best for me with a carbide tipped coarse blade. Keep the blade just above the sheet just breaking through and it will cut nicely, a helper for full sheets helps also.
I made a aluminium gas tank for a boat and cut it with my plasma cutter. It made a nice cut in 3/32 material but it was a pain to weld. I spent more time cleaning up the edges, must remove the oxidation caused by the cutting process.

If you have a choice use a saw and not the plasma

 

[arkangel06]

just get a manual shear that can cut upto 125tho

 

[AGRITRAC]

Evolution 230 with alu blade will cut 12mm like a laser cutter had cut it

 

[Robert]

Agritrac
That is a nice saw. I still vote for a table saw in aluminum though. With a mist coolant system 3 inch + can be cut (Dewalt commercial 3 phase machine 4hp). I cut 1/4 inch on my Craftsman (Sears) with no trouble. A manual shear that would cut .125 would take too much floor space and be limited to only 4 foot wide cuts. Nice to have in a larger shop though.