Half inch Manganese with a Hypertherm air plasma help

[WSS]

Anyone have suggestions with settings for .5" manganese? I am using a 1650 and have tried 60, 80 and 100 amp parts. The best so far is 80a @24ipm and 146v. Piercing is the big problem, delay is at 1.75sec. and pierce height is up to .28". If the machine moves before it gets through it is ugly, it will toast a shield and nozzle in a micro second. Stuff stinks too, very very smoky.

This material is non magnetic too. I have 799 pierces to make doing 1.125" holes.

Thanks,
WSS

[BBchevy396_]

I cant help you with cutting the stuff, but be very careful working with manganese steels, and protect yourself accordingly. It is very bad for you! More so than most metals.

CDC - Welding and Manganese: Potential Neurologic Effects - NIOSH Workplace Safety and Health Topic

[WSS]

Thank-you for the link! I suspected this was the case and used my underhood respirator for the entire project. There was an immense mount of dust left over. I will have to blow out the tray before the next plate goes on. Even cutting A36, there is left over manganese dust flying about. A water table would have solved a good 90% of the problem.

I asked the guys that supplied the steel and they said not to worry, they cut it all the time. Neurological damage is hard to pinpoint!

WSS

[jimcolt]

So...how did the job turn out? I'm still in So. CA....

Jim

[WSS]

Originally Posted by jimcolt So...how did the job turn out? I'm still in So. CA.... Jim

Went great. Thanks for the info and direction. Decided to run a little higher volts to keep away from the plate. Even pierced a 1/16" higher. I was able to get 400-500 pierces per nozzle/electrode. I changed them both at the same time for quality whether the electrode needed it or not.

I bet The desert got a little cold last night.....

WSS

[jimcolt]

Wow....a lot of holes, looks good! Manganese is a bit tough...good choice on the increased pierce height and cut height.

Cold in the desert? I'm from NH.....it is cold when it is -30 like it was for 3 days last week! I was walking around in a T shirt when most of the locals had winter jackets and gloves on!

Jim

Originally Posted by WSS Went great. Thanks for the info and direction. Decided to run a little higher volts to keep away from the plate. Even pierced a 1/16" higher. I was able to get 400-500 pierces per nozzle/electrode. I changed them both at the same time for quality whether the electrode needed it or not. I bet The desert got a little cold last night..... WSS

[WSS]

It was 60f here all day and I wore a carhart most of the day. Interesting, but there are more deaths in that desert from cold than heat. People expect it to be hot but do not plan for 40 degree weather! Barstownians have the hardest time, they go out to build their rock piles/shrines and lose track of the time, once the sun goes down direction is hard for them as well.

Thanks again for the help!!

WSS