Scratch Built Wishbones

[fluidfloyd]

RexRod

David,

Since it will be a long cut I think you would need a tapered backup clamping bar so as not to get any cutter chatter in the middle of the rail. Now you being a much better machinist then I, probably are doing that now as we speak.

As to how Henry did it in his day, I would have to believe they stamped or pressed the two halves with dedicated die sets. In those days everything was big, brutal and heavy. No problem for guys of the day with that mindset. Have fun!

George

 

[RexRod]

George, you are right about supporting the base of the platform I put the arm on. I had planned on supporting it in several places... BUT... I don't need to do that now. I have solved my long cut problem...... Because..............................

Story: I called a friend of mine today to talk about plasma cutters. He has a ton more experience with these pesky machines then I do, so I thought I would get his views before I did much online research. Of course he gave me the whole "you better spend the money up front and get a good one" spiel. And "don't buy a wimpy one." We both think alike.

Then he really surprised me. He told me to come on over and he would loan me one. I said "What? I didn't know you had a plasma cutter?" I feel super lucky today, that's for sure.

So off I go in my beat-up rusted JapRod pickup, and looky what I got to play with for a while:

He said it's rated to clean cut something like 1" thick steel, and sever cut up to 1.25". I bet on 1/8", you need to travel at 100 inches per minute feed rate, or more.

A little big for what I need, but hey, beggars can't be choosy!

David

 

[fluidfloyd]

David,

I must not be living right. First you got my free HP plotter and now this. I got to change my ways. Those ESAB machines are really good units and should do you a good job. Have fun.

George

 

[RPM]

George, you are right about supporting the base of the platform I put the arm on. I had planned on supporting it in several places... BUT... I don't need to do that now. I have solved my long cut problem...... Because..............................

Story: I called a friend of mine today to talk about plasma cutters. He has a ton more experience with these pesky machines then I do, so I thought I would get his views before I did much online research. Of course he gave me the whole "you better spend the money up front and get a good one" spiel. And "don't buy a wimpy one." We both think alike.

Then he really surprised me. He told me to come on over and he would loan me one. I said "What? I didn't know you had a plasma cutter?" I feel super lucky today, that's for sure.

So off I go in my beat-up rusted JapRod pickup, and looky what I got to play with for a while:

He said it's rated to clean cut something like 1" thick steel, and sever cut up to 1.25". I bet on 1/8", you need to travel at 100 inches per minute feed rate, or more.

A little big for what I need, but hey, beggars can't be choosy!

David

Yep about 100 inches a minute. I just have a 40 amp cutter on the CNC and it will cut 1/8" at 100 inches a minute.

Clamp a straight edge, as a guide, onto what you are going to cut and slice it up.

 

[RexRod]

Yep about 100 inches a minute. I just have a 40 amp cutter on the CNC and it will cut 1/8" at 100 inches a minute.

Clamp a straight edge, as a guide, onto what you are going to cut and slice it up.

Ron, Great chart! What happens when you go too slow? Do you get slag on the back side like with an Oxy/Acetylene cutting torch?

 

[RPM]

Yes you get what they call dross on the back side. It comes off very easy.

Be very aware of the sparks from that plasma as they are much hotter than those from a torch. You can start a fire real quick. Don't ask how I know that. And the dust the dust is awefull try not to breath any of it, or let it get on any of your machines. With the oil on the bed of the lathe and the plasma dust it is like putting valve grinding compound on the ways.

 

[RexRod]

Thanks Ron, all of that is good to know.

What about cutting over water? I've seen machine and manual setups where people will cut over a barrel of water to catch some of the spray. In fact, I saw one CNC machine that cut underwater. The fluid was some kind of bright fluorescent green color, or something like that. This might be the stuff:
GreenCut Biodegradable Cutting/Misting Fluid - Use in Plasma Arc Cutting Tables

Flame cutting is the same way with all the metal dust it makes. With oxy/acetylene anyway. The NG/LP and oxygen cutting setups I've seen don't seem to have as much of a dust problem.

 

[Jim Henderson]

This is a good read