stainless steel

[fusername]

Looking to do a bunch of prototyping w/ square tube. making some small steel frames and I am thinking stainless is a decent investment. I am wondering which alloys would b e best, I need to weld and drill it, not a ton of machining really. My needs are at this point (I think)

corrosion inhibiting properties
Ease of welding

I only need to drill a few holes in general, and I have a small press I can do most of it on, so that doesn't worry me. 304 and 316 are teh two big ones listed on mcmaster, w/ 316 being more resistant to rust, but definitely not cheap. I am going to be buying from a metal supplier, so I will have likely a wider range of alloys to chose from than that. I can probably afford to spend a little more if it gives me what I need, so does anyone have any good insight to share here? 304 seems to be the ticket so far.

[Ol'fogasaurus]

http://www.engineersedge.com/stainless_steel.htm

http://www.brazing.com/products/Weld_St ... _chart.asp

http://www.machinist-materials.com/stainless_table.htm

This should get you started. Don't look at availability first, look for the use first then check to see if you can get it and how much. Compromise/overlap is OK at times as long as it meets most if not all of your requirements.

Lee

[falcor]

I've been 8 years in the stainless business so I hope i remember something.
If the frames will just be used indoors then 304 is good enough. For outdoor use 304 might work but 216 is safer especially in coastal regions. If possible buy European/US made steel. The 304 standard is very wide so a 304 from Asia might be very different from one made in Europe.

The most important thing is to remember to not use metal cutting blades and other tools that have been used on plain steel on the stainless steel. This will cause contamination and you will easier get surface rust.
If you do any welding use the right fillter material and clean all weld oxides directly after welding with a stainless wire brush. For perfect appearance the welds should be pickled but that's really overdoing it.

[Stray Catalyst]

Handle it with care. One thing I learned (the hard way, of course) when I was working for a sheet metal prototyper - stainless steel naturally forms an edge that a Ginsu knife would be proud of, and will always find ways to make you bleed. If it comes from a shear, especially a dull one, you'll be amazed at how deeply it can cut you.

[fusername]

just ordered two new sets of work gloves, youngstown best gloves by and far I ever have used, my third set in two years, and I am trying out an insulated pair this time. I will keep them on for this good stuff.

Falcor, thanks for the tip on cutting blades, I had heard that in the past but COMPLETLY forgot about it. With the price drop going from Mcmaster to my local steel distributor, and the mcmaster price not breaking the bank, it sounds like I can use the nicer alloys. This is for some field maitenance stuff, and while it probably will be powdercoated in the end, to keep it raw for a year and not show its age would be really slick.