Plasm cutter Question

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My desire/need  for a cutting tool like a Plasma Cutter would be to (in addition to the obvious sheet cutting)1. Cut say 1 x 1/4 SS flat bar along the edge to modify it so it is no longer recognizable as a piece of 'flat bar'. (squiggles, curves, or tapers)2 Cut 1/2 SS round along its axis to change it into a 'D' shape. I'm currently doing this with a grinder/ flap disk, which get's tedious if your doing more than a few inches. Here's an example:It's kind of blurry but I think you get the idea.So it's pretty clear to me from what I've seen, that #1 is one of the things that plasma cutters do well. But can it do # 2 - cut along a piece of round stock? How powerful a unit would I need?Your thoughts? Attached Images"We live in an age when unnecessary things are our only necessities. "   - Oscar WildeMaxstar STL150Eagle CPM30 Bender
Reply:Why wouldn't you look into a band saw?
Reply:You'd need a powerful plasma to cut 1/2" round SS without making a mess. 60 amp or so. You can buy 1/2 round stock though, already in the shape you want. Beats the heck out of trying to cut a piece of round bar lengthwise.I'd consider heating and hammering the edges of the flat bar to the shape I wanted. I've got some 2" x 1/4" flat somewhere with hammered edges somewhere. I bought it that way, it's really nice looking stuff.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:Well, the bandsaw is something I hadn't really thought of. I'm thinking now, though, and I  guess it would be slower than I want. Also, as I'm making this distortion of the round bar to 'd shaped', I also am rotating it, to give the illusion of twisting it. Oh, did I mention that I'm also twisting it on a bender, to give it several dimensions of curve and twist....So the bandsaw doesn't really work for me in this particular application, I don't think.I had a forge for years, so I've done the heating and hammering thing. I'm thinking more along the lines of 'freeform fabrication', if you will.If you look at my photo, notice how the tip is tapered while twisted around the axis. I did that all with flapdisks. If I could get the bulk of the metal removed quickly with a Plasma cutter, I know I'd still have to do the finishing with a flap disk.As you can see, the final finish is mirror smooth, so that took enough time as it is.Maybe the real question here is, has anyone actually tried cutting 1/2 round 304 SS lengthwise with any success?"We live in an age when unnecessary things are our only necessities. "   - Oscar WildeMaxstar STL150Eagle CPM30 Bender
Reply:I have cut SS with the plasma some. No round stock however. It does leave a bit of slag that needs to be removed. Not sure if thats due to not having the settings quite right, cutting by hand vs machine, or just the way it is. I suspect partially it's the way it is. The slag closely resembles the "sugar" that forms on an unbackgased tig weld. Makes sense since the principals are very similar. I don't have any gas for the plasma right now I believe, I'll look tomorrow if I remember. I should have a small chunk of SS 3/8" bolt that I just cut for another project, If I can find the 2 (and remember) I'll give it a try.
Reply:You should easily be able to cut a flat as you show on 1/2" round. If you want I'll cut a piece of 1/2" steel round rod and take a couple of pics...I don't have any round SS.Jim
Reply:Jim, that would be great. Maybe this pic gives a better idea of what I'm doing. Notice in the lower left, how the cut curves around the axis. Also, on the upper right, you can see how I start the bevel and gradually taper in to the full cut.Sorry about the glare, my buffer got a good workout on these pieces. I was trying to make mirrors out of them.I've had a lot of stuff cut for me on a CNC machine, so I realize that there'll be lots of finishing still to do. But if you can imagine trying to do several feet of that with an angle grinder, you understand why I'm interested in a better way. Attached Images"We live in an age when unnecessary things are our only necessities. "   - Oscar WildeMaxstar STL150Eagle CPM30 Bender