DR plasma cutter

[wayfarer]

What are you guys using for air? Plumbed into your shop air or using a dedicated compressor?
I just unpacked my cut50 and the literature says 6.4cfm and 100psi. That is a fair amount of air to provide.

 

[smallfoot]

Right now, I'm fabbing up a bracket to put my new filter on a portable compressor I'm using for air on the DR. I can see hooking permanently to a whole shop system if this was gonna be used that much. My use will be minimal and I'll keep it with the portable air supply so I can move them around more.

 

[Old Iron]

I have a Ingersoll Rand shop compressor 19.5 cfm @ 100psi and I mounted the M60 filter on the plasma cutter so I can hook it to any line in my shop or any where else.

 

[wayfarer]

Until I started looking, I had considered a smaller unit so I could put everything on a cart...the smallest unit that I found with 6.4 is quite large, at least for a cart, so was just wondering what you guys were using. Looks like I'll plumb into the shop air.

 

[Old Iron]

Unless you get lucky, I don't think you'll find a portable compressor that will maintain 6.4 cfm at 70 psi
A plasma cutter requires around 70 psi continuously, to cut correctly. You can get by with 60 psi.
The following compressors would handle your needs at 70 psi if you use the plas in short intervals.

Senco PC1131 Compressor, 2.5-Horsepower 4.3-Gallon

Emglo AM780-HC4V 2 HP Electric Air-Mate Compressor

 

[wayfarer]

I have a couple of portable units in the shop that make 6.4 at 90psi but they are kinda big. Since most of my equipment is a bit 'old' (not unlike me), I just wondered if something newer might be in the market place that was smaller.
Thanks.

 

[vht]

I wish I could find time to use mine. I have a 6 gal compressor that builds 150 psi, don't know if it would handle it or not. Never thought about a cart and compressor combined. I 'll more than likely use my shop compressor, but that got me thinking.

 

[DozerII]

Some more use on my Cut 50. I have an old water pressure tank build date 16-10-44 that I'm making into a chimmea for camp, It is rusty 1/4" steel and I cut 4 large opening in it with ease. I found the plasma eats consumables at a fairly fast rate on the rusty steel. [[

 

[Old Iron]

A suggestion,
I install new consumables for the jobs that need to be cut clean and square on the edges until they start to cut on a bevel then, I switch them out, I keep all the consumables in a Holley jet box in the category of wear on them, I then use them on thinner materials until they start to cut bad.
Rust is hard on tips so, I use the worst ones for just the type of job you're talking about until they won't fire or cut, I then throw them in the copper recycle bucket.
You will get more use for your money that way.

 

[DozerII]

A suggestion,
I install new consumables for the jobs that need to be cut clean and square on the edges until they start to cut on a bevel then, I switch them out, I keep all the consumables in a Holley jet box in the category of wear on them, I then use them on thinner materials until they start to cut bad.
Rust is hard on tips so, I use the worst ones for just the type of job you're talking about until they won't fire or cut, I then throw them in the copper recycle bucket.
You will get more use for your money that way.

Thanks for the tip OI

 

[DozerII]

Yesterday I was making some cuts in 3" x 3/8" flat and found that I was cutting 45 degree angles instead of a verticle cut, changed the tip and found it did the same. So after close inspection I found the outer copper tip with the hole in it has a cross ground into it which I believe is supposed to take care of any burr from drilling the center hole, but it looks like they are drilling the hole after grinding in the cross an on 50% of the tips it left a small burr which will direct the flow at an angle. [S

 

[Dr Crankenstein]

Did you change the tip and the electrode? If the electrode is burned at all, the outer tip will pee around corners...

or, you've found the limits of your machine...

or, you have dirty air...

or, too much pressure...

.

 

[Old Iron]

Like Doc said, You should always change the electrode and the nozzle at the same time.
Anytime a plasma cuts on an angle, the nozzle is worn out or the torch is not square to the material being cut.
The cross grooves are for air relief on a drag nozzle.
I used one of the small Lotus plasma cutters last weekend and was very impressed on the way it worked.

 

[DozerII]

Did you change the tip and the electrode? If the electrode is burned at all, the outer tip will pee around corners...

or, you've found the limits of your machine...

or, you have dirty air...

or, too much pressure...

.

I learned real quick you have to change the parts together, could have dirty air.

Like Doc said, You should always change the electrode and the nozzle at the same time.
Anytime a plasma cuts on an angle, the nozzle is worn out or the torch is not square to the material being cut.
The cross grooves are for air relief on a drag nozzle.
I used one of the small Lotus plasma cutters last weekend and was very impressed on the way it worked.

I will post a picture of the burr on one of the tips.

 

[Old Iron]

OK, consumables being mass produced, it's possible to miss something like a burr. The plasma arch can be deflected and cause it to cut angularly.
With moisture in the air supply, it'll eat a nozzle instantly.
If a piece of slag gets blown into the nozzle it'll do the same thing.
Too much or not enough air pressure, too fast or too slow will cause more dross.
You cannot drill a nozzle out to square the hole back up, I know

 

[smallfoot]

Got the chance to give mine a little workout and me a chance to get used to the new machine. Holy Cow, 1/8" steel is like butter. I wasn't doing anything that needed to be close tolerance work and I'm probably pushing my tip past it's limit, but I'm impressed. I started with my settings fairly high and have done nothing but back everything down to cut this stuff. Getting some play time on this will make a difference but I know I saved a bunch of time today on my project. I cut 4 large pieces, all the same size. The first one, I did with my grinder and a disc, the other 3 were done in less time on the plasma cutter. I'm likin it...

 

[DozerII]

Here's some pictures of the tips, it's crazy how the hole in everyone is different
one doesn't even have a hole.

 

[Old Iron]

I see what you're saying
To use the badly or not punched at all nozzle, I would drill them out

 

[DozerII]

I have done that on a couple, the one on the right in the second photo will cut at a 45 deg angle with the torch level

 

[smallfoot]

OK guys, Been dancing around a home made auger, making foul noises and obscene gestures for days now. Beating and cutting old tractor parts is usually taking any kind of equipment you use for a pretty good ride. So I got some more time with the plasma cutter. I'm happy to say The DR is working great. No issues at all. I am getting pretty used to it....
I cut lots of 1/8", quite a bit of 1/4" and 3/8" and lopped steel pins off that were 3/4". I'm convinced it'll cut when I need to as long as I keep up with consumables. I did find, however, that not all consumables are alike. Find ones that your gun likes and stick to them. Seems like anything else mass produced nowadays doesn't get much quality control. I think Dozer might be experiencing some of this with his consumables. Even a dirty tip and electrode is one cutting fool. I had one blow out the side.......not good for a guy with a face full of hair...Am not really sure what went on but suspect without looking, I probably put one of those tips with no hole on the gun. It was tip, electrode, swirl chamber and cone change time there.