Plasma Questions

[Hilbilly]

I'm thinking of getting a plasma cutter and have a basic question. With my OA setup I get poor cuts (lousy operator) but am getting better with some practice. The biggest problem seems to be that I cannot get the cut speed right and when that happens I loose the cut and have to restart. That causes a hole in the steel and I loose my straight line. Then there are notches along the side of the cut that I have to grind out or fill in and then grind. Will the same thing happen when using plasma or is it more forgiving for the novice?

 

[Shield Arc]

Will the same thing happen when using plasma or is it more forgiving for the novice?

Nope same thing will happen with a plasma.
How about getting a burning square to help you?

 

[Hilbilly]

Thanks SA. You just saved me a bunch of money.:cool2:

I might as well just stick to the OA for cutting, since I already have that. I rarely work with steel so I don't have much experience, although I'm getting a little now that I'm fabricating a grapple. I am using a straight edge to guide my cuts but I still don't get the speed right. Getting better but still get those nasty restarts. Between those points I'm pretty happy with the results.

Is the speed square used as a guide or to mark out square cuts? I use a square now for marking and a piece of angle for a straight guide. Is the other tool a circle guide and is it made by you or bought?

 

[Shield Arc]

There are a lot of magnetic burning straight edges on the market. I've never been real good with a torch. Over the years I've worked with some guys who were just amazing!
One thing I do, is try to stand where I can see the cut, but also see the amount of sparks falling from under the cut. This helps me with travel speed.
In my opinion plasma are a luxury, unless you're working with non ferrous material. For the cost of a plasma, compressor, and air dryer, you can buy a lot of oxygen & acetylene. You can always switch to propane and save on the cost of acetylene too.

 

[Shield Arc]

Oh I forgot! Yes I made the circle burner. I have a rotating table, I can make some nice circle cuts with it. The burning square I posted a picture of is used to hold the torch steady while burning. I added the aluminum angle for the plasma torch.

 

[jake98]

Those wire bugs on the square stock is a great idea! I'm so stealing that SA! I've had some success using drywall 'hat channel' with a filler piece under it, to give the tip height, for a straight edge.

 

[Rustyiron]

Although not nearly as experienced as Shield Arc, as I read through his responses, he was taking the words right out of my thoughts! :laughing: Practice with the o/a & spend the plas. money on something else. Grinder's, saw's, clamp's, drill's, on & on. In a closed (winter) shop, the plas. also makes a terrible smelling smoke, unlike anything else. Makes the grinding & welding smoke smell like an air freshener in comparison.

 

[Hilbilly]

Thanks for the replies. I've been outside welding and cutting most of the day, working on my grapple. Although I've made a few mistakes that had to be redone, I'm still enjoying this build. Lots of new challenges for me. I'm also,getting better at OA cutting. Not good but better.

My oxy tank reads 300 psi and the gauge stops at 200, so I'm pretty much out of oxy but still have 130 psi in the acetylene tank. Tomorrow is a holiday here so I can't get the oxy tank filled until Tuesday. I've only got a 55 cu ft tank and it expires in September. So I'm going to get that one filled a buy a bigger too. Figure I'll get a 110 cu ft tank and that should last me a long time.

Now that I've been talked out of getting a plasma cutter I'll have to find something to buy. Woohoo.:dance1:

 

[Scooby074]

Its been covered, but there is no replacement for practice. OA is fine and has been around forever. Consider shifting to Oxy propane. Its a pretty cheap change to make, just a tip usually, but you may need to change bottle adapters and youre supposed to change hoses (but thats overkill for home users if you have a quality ace hose (type R) IMHO). Switching to propane cuts the main cost of using oxy fuel IMHO. Acetylene has gotten foolish expensive.

 

[Shield Arc]

Propane does make some nice cuts.

 

[dragoneggs]

Propane does make some nice cuts.

Wow that does look pretty clean from here!

 

[Hilbilly]

Its been covered, but there is no replacement for practice. OA is fine and has been around forever. Consider shifting to Oxy propane. Its a pretty cheap change to make, just a tip usually, but you may need to change bottle adapters and youre supposed to change hoses (but thats overkill for home users if you have a quality ace hose (type R) IMHO). Switching to propane cuts the main cost of using oxy fuel IMHO. Acetylene has gotten foolish expensive.

I just found out about the possibility of using propane from this forum and did some checking. I have type R hose that looks like new but what I've read that I need type T. I would also need some sort of adapter for my propane tanks and different cutting tips (probably only 2). But I really like the idea of being able to go the local gas station to get fuel. I think I'll check it out when I go to the city.

SA on my computer those look like laser cuts. I see you have developed all sorts of cool jigs and automation tools for welding. Must be nice.

 

[wldrbob]

well i taught a few welding classes ... plasma is way easier for a newbie to learn and as for leaving holes along the side well practice helps .. plas is easier to start back in the kerf

 

[Hilbilly]

well i taught a few welding classes ... plasma is way easier for a newbie to learn and as for leaving holes along the side well practice helps .. plas is easier to start back in the kerf

I was hoping that plasma would not create the little gouges when the cut is lost but if not then there really is no point in me getting one. I am getting better with OA cutting, just from the work I'm doing on the grapple build and for the $1500 I was about to spend on a plasma I can get a lot of other goodies. All my cuts today were good enough for me and the one I screwed up yesterday was easy to fix. A little welding to fill the hole and then some grinding. Not production work by any means but I am enjoying the learning experience. So far I think my biggest issue is with longer cuts where I have to reposition my arms / body but I'm sure this will come with more practice.

 

[Hilbilly]

Just to give you and idea of how much cutting I do, I bought the OA set up about 10 yrs ago, including the tanks, and my oxy tank expires in Sept of this year. When I bought them I lived in the City and had a specific hobby project that warranted the need for an OA setup. Well that was my excuse at the time. In the 10 yrs I've had them, I refilled them once and they are small tanks. I think the acetylene is 40 cu ft and I know the oxy is 55 cu ft. I use it a lot more now because I retired 6 years ago and moved to the country and there are times that something made of steel needs to get repaired, or as in this case, I have decided to make a grapple instead of buying one. So I suddenly have a need to do a lot more cutting than I have in the last few years and since I am not good at OA cutting (lack of practice) I thought that plasma would be the magical solution for me. But it appears I was wrong.

In any case I am getting better at OA cutting and stick welding. I think it just takes practice and I am getting a lot now, with my grapple build. Maybe a little more than I should, because I have to redo things sometimes.

Oh I forget to mention, I'm not getting a contract, since I can buy a 110 cu ft oxy tank for $220 and get it filled for $28. The acetylene is a different story. A 75 cu ft tank is $200 to buy and $100 to fill. That is why the propane looks so inviting. I already have the smaller tanks and the welding / cutting equipment I need. For now anyways.

 

[wldrbob]

any body that dosent have to redo the odd thing never did much lol

 

[Hilbilly]

There are 2 good things about having to cut apart a weld I just completed; the first is that I get see how bad or good the weld was and the second is that I get more practice.

 

[wldrbob]

plas is pretty good for cutting welds you know lol

 

[Hilbilly]

I think somebody might be trying to talk me into getting a plasma cutter.:wink:

Even though I'm the guy that says to his wife " look honey I can pay somebody $2000 to do the job or I can do it myself for $1500 including materials and the cost of some new "essential" tools. I'm pretty much convinced that a plasma is not the "essential" tool I need to get this job done. lol.