stainless cutting/ 3/32

[foolwelding]

Hello i have some stainless pieces that I want to cut into some test strip,was wondering if I can use a jig saw with fine tooth blade to cut,also is it ok to weld with straight argon or should I get some tri mix to play with. Thanks for your time.

[SundownIII]

3/32" SS is going to be tough to cut with a jig saw. Will eat blades like crazy. If you don't have access to plasma or a shear, you're probably better off with a cut off wheel on your grinder.

Straight argon is fine if you plan to tig weld it. If you're using GMAW, you're better off with the tri-mix. Straight argon won't work.

[jimcolt]

Find someone close to you with a plasma cutter....you can cut 3/32" with virtually any plasma. Use a straight ede to quide the torch. If you were in NH I would do this for nothing for you as it will likely take just a few seconds.

Jim

[foolwelding]

Thanks for the free offer Mr Colt wished I could have been closer im sure I cold have learned alot,also thanks sundownIII wow even with cut off wheel on grinder still alot harder to cut than steel,will have to find small plasma to make my life eaiser,

[SundownIII]

foolwelding,



Stainless steel is a bear on most any cutting tool.

The plasma is the best course of action, but not to dispute Jim, it is not without it's shortcomings also. SS cut with an air fed plasma still has an edge which must be "prepped" prior to welding. The oxides left behind a plasma cut, will really futz up a tig bead.

I have the Hypertherm PM 600 and the PM 1250 and would be happy to cut the coupons for you if you're close to VA. Personally, when I'm cutting SS coupons, I just go to my buddy's shop and shear them. For detailed cuts, we do them on the water jet.

[jimcolt]

Sundown is correct that an air plasma cut will leave an edge with an oxide layer on stainless. This edge is minimized by matching the power and nozzle orifice size, as well as the standoff and cut speed to the materials thickness. On 3/32" stainless a quick pass with a flap disc will completely remove the oxide layer....which is roughly .002" thick. If you cut too slow, with too much power, or at the completely wrong standoff....then the oxide layer and edge metalurgical effects will definitely get worse.

Jim Colt

[SundownIII]

Jim,

Didn't want to appear negative about the plasma cut.

Got to admit, that "quick pass with a flap disk" is a LOT easier/quicker than trying to cut SS with a cut off wheel.

Now on aluminum, we're into a whole different story. Nine times out of ten, I'll reach for a saw (circular, band, jig, hole) before I have to deal with the oxides left from plasma cutting (here a carbide burr is your best friend).

[jimcolt]

I agree on aluminum that...if you have to tig the edge, then the plasma will provide some fairly deep contamination. I have Mig welded many plasma cut edges and had no issues with weld quality....although I admit I know more about plasma cutting than welding...in fact I suck at Tig!

Our industrial high definition class systems use H5/N2 (H5 is 95% nitrogen, 5% hydrogen) as the plasma and shield gases for uncontaminated stainless.

Jim

[Rbeckett]

Jim, would you have a short vid of the high defs with that gas mix in action? Sounds like it must be a monster machine. Thanks
Bob

[jimcolt]

Bob, I do have a video.....but I'm not sure how to attach it....I'll see what I can do.

There are four current high definition class systems....130 amp, 260 amp, 400 amp, and 800 amp. The processes are really high definition class plasma untill you get above 400 amps....then it is brute force and high energy physics that melts a 3/4" wide swath through 6-1/4" stainless or aluminum.

Jim