SS fishmouth with plasma

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Here are a few cuts to show the amout of cleanup necessary after plasma cutting SS.Machine was turned down to 30amps for the 2" tube.Some pics are of 2" about 1.4mm thick SS tube.  No template was used (had a shakey hand today, big night ).  It was more to show the affect is has on SS and the amount of cleaup required before welding.I'd like to see a plasma fishmouth on 1"tube  Attached Images
Reply:If you're making a square handrail, (not a stair rail), from pipe I find the esiest way is to cut two 45 deg cuts on the end of the pipe so that they don't quite meet. Leave a small square piece on the end about a 1/4" or so wide. Finish it off with your minigrinder by rounding out the bottom of each cut.That cut made with the plasma would be brutal to clean up, (not pickin' on you Larry GBG)....Mike
Reply:That cut was made in response to another thread.
Reply:Originally Posted by mrmikey  That cut made with the plasma would be brutal to clean up, ...Mike
Reply:You need to make a slip over guide with the next size tubing....I used to use a fiberglass tube....with a setscrew toi hold it in place. Put the smallest set of consumables in the plasma torch (use FineCut if you have a Hypertherm)....and turn the power down to about 20 Amps. Drink coffee or beer, whichever steadies your hand....and get comfortable and guide the torch at a reasonable speed. There will be about an .005" oxide layer on stainless that will need a quick grinder pass.There are plasma systems....not hand held, mechanized only....that can cut stainless steel with no oxide layer whatsoever. For thin SS with high definition class plasma we use F5 (95% nitrogen, 5% hydrogen) as the plasma gas and nitrogen as the shield gas...shiny, clean weldable edge. Jim Colt
Reply:DSW,You obviously know the thread im talking about.Maybe some will say i didnt try hard eneough for a good result.I'll bung up another one in the next couple of days with less amps and a better hand.  (Stay off the coffee after a big night )I dont have the fine cut consumables ( if Hypertherm would like to send me some )so it will be done with normal sheilded 45 consumables.With the consumables i brought with the machine, and at the rate im going through them, i'll have enough for the next 5-6 years.
Reply:i thought it was called "mitreing a tube" or "tube notching"..........."fishmouth" that's cool.i know i've heard that before , but maybe not in a long time.i like "fishmouthing a tube" with a plasma too.        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:Sorry Larry,I didn't read back far enough! Tube is pretty small diameter for any hand plasma application....even with beer or coffee to help.Best regards, Jim
Reply:jimcolt,have u thought of some kind of notching attachment for tubes , to use with the hypertherms yet..?that would be.....real cool.        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:Like I said......a larger piece of tube formed with the fishmouth shape that clamps over the one you want to cut......I made a bunch of these out of fiberglass tube many years ago when I was fabricating stock car roll cages. It always worked well for me......that was all chrome moly and carbon steel tube about 1-3/4" od.  SS is a lot tougher to get a good cut.Jim
Reply:I do same thing as Jim does with the slip fit tube as a guide but instead of set screws I use thumb screws. I use that set up for making all my clothes line  T-Poles instead of using a tube notcher. So far I have made over 1,500 sets. of those poles.http://weldingweb.com/vbb/showthread.php...y+making+polesCo-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:tube notchers are a pain sometimes. Especially if the Hole Saw is dull. And the Good Milwakee's and Dewalt's etc., are like nearly $20 apiece. An expensive Collection i must say. Thanks for sharing        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:Yep I have a pipe notcher and those bi metal cutters and carbide cutters get very expensive FAST~Co-Own CNC shop:Miller :1251 plasma cutter, MaxStar 700 TIG/Stick, & XMT 456 Multiprocess Welder.&  2 Hypertherm HPR260's Plasma CutterSorry I had a bad stroke but now I am back.
Reply:Do the cut characteristics vary much with the type of stainless?