Cutting Stainless Steel

[Captain PartyMarty]

Hi Guy's

I know some of you are fabricators so maybe you can help me out with this question. I have a personal project where I will cutting lots of 304, 14gauge stainless sheet metal. all the cuts are going to straight but need to be accurate enough to weld together. Last time I did a project like this I got a diamond coated blade for the skill saw and went to town, it was a lot of cutting but it got the job done. I have been looking at plasma cutters and wondering if it would be faster to cut the sheets with a plasma cutter. My question: Is a plasma cutter accurate enough and does it product a nice clean cut? Also what is the difference between between the 2000 dollar miller machines and cheep 300-500 dollar machines?

CPM

 

[SpringVelocity]

How many parts are we talking? Are they just basic shapes? I cut stainless on my CNC plasma a fair bit.

The edge is clean but you get a bit of oxidation. You have to fiddle around with your speed and amperage. I generally only go 40-42amps at most that thickness. By hand that can get tricky.

And yes there is difference in plasma cutters. I only recommend Hypotherm.

For welding I would just use 80 flap disc if you are worried about welding edges. I find it generally isn't that much of an issue.

 

[fishin solo]

use a straight edge for a guide Marty prob easiest way with what you have for tools/equip. You can buy drag tips for a plasma that work great but just clamp a straight edge as a guide.... don’t forget to figure out what you need to add to your measurement/lineup for the center of the plasma tip...... you do get what you pay for when it comes to welding machines/equipment so keep that in mind. Like SV said hypotherm is awesome Miller is good but is no hypotherm. Try western gasco talk to billy or his brother rob they can get you sorted. Good guys to deal with and honest.

 

[Captain PartyMarty]

Roughly 2500 in's of cutting length, all different lengths so going to shop is bit of a pain as each piece needs to fit to barn.

 

[Foxsea]

I've had metal cut for me by different shops. Heavy shears can do it but CNC is the way to go: plasma table is quick and accurate. Decent edges but water jet is perfection.

 

[fishin solo]

Hahah I was waiting for someone to say waterjet

 

[SpringVelocity]

Laser is the best for stainless in that ga not waterjet. Just a piece of advice. You might want to see if you can just get someone to CAD those up and get some DXF files. Then take them to a few shops. Without seeing it sounds pretty basic. Some of laser guys on mainland have been hurting for business. Just a thought.

 

[Offshore]

If you’re going to need standard widths you could have the sheet sheared and then do the lengths by hand. Welding stainless that thin your really going to want a clean edge. Cutting by hand with a plasma and grinding clean to prep for welding will probably be more work and put more heat into the metal. The edge from cutting with your saw or a zip cut will be weldable with less warpage.

 

[Fixit]

Over 200 feet of cuts? Does that mean 200ft of welding too? What exactly are you doing? I made a 2x2x1ft firebox for a cedar hot tub from a sheet of stainless amd must have gone through 20x 5” zip discs. Seems like the stainless just eats them up.
ive always found stainless hard to weld with mig. Seems too cold initially then too hot at the end of a bead

 

[Silvercreek]

If it's straight cuts get someone to shear it, fastest and cleaneast cut