250ci Plasma won't hold a flame

[ROSinclair]

My cutter will not hold a flame. I replaced all the consumables, but that didn't solve my problem. I have to keep pulling the gun trigger; the torch will fire for a few seconds and then stop. If I pull the trigger it will fire again and last another few seconds before it again goes out. Any ideas on what's wrong before I take it in for service? Thanks (Happy New Year to All) Robert

[mikecwik]

what are all your parameters? have you used them before with success?

[ROSinclair]

250i Plasma Cutter

what are all your parameters? have you used them before with success?

I'm not sure i know what you mean when you ask "what are all the parameters?", I installed all new consumables. The cutter has a built-in compressor and I plugged the unit into 115V outlet (just as I always had before the problem started). I pull the trigger on the torch and a flame initiates but then goes out after a couple seconds. This process is repeated each time i pull the trigger on the torch.

[bandsawguy]

By parameters he means what settings on the machine. Also stating what material and thickness you are cutting would be helpful in determining if its a machine problem.

[mikecwik]

is it shooting straight through the material? maybe try a quicker movement.
call hobart!

[JimYo]

make sure the grounding wire has a good connection to the grounding clamp... I had to redo mine on my 250CI ... Jim

[enlpck]

Second on ground problem. Symptom is that the pilot arc will strike, hold for a few seconds without cutting, and then the machine cut off because it doesn't see cut current.

It may be a bad contact with the workpiece, bad connection at the clamp, broken wire between he machine and the clamp, or the wire connection in the machine. Common issue and easy to check and fix if this is the problem.

If you can't find it and fix it, call Hobart.

[VSTAR1100]

I have the same machine, I've had the same issues. What I figured out is that the machine has to dry out before you can use it(sounds silly). The compressor will create condensation when in use. The next thing is the water goes through the diffuser to the electrode. If you look at the end of the electrode it will resemble a bulls-eye and the copper cups opening will be deformed(opened up). the water being forced through by the compressor has grounded out the electrode and the cup burning/opening the gap(kinda like a spark plug with too much gap. I have found just replace the cup and electrode also, while you have it down use some 000 steel wool and clean the contact ring on the copper ring forward of the trigger before you reassemble.


F.Y.I. I learned this from this forum.................................

[sageygts]

I have had same problem

I would check your ground\ cable.

[SidecarFlip]

I am having this same problem.

Off to go check the ground, it seems...

regarding the water in the line-- would it be smart to install a water seperator?

Where? The compressor is on board the machine.

[galaxieguy]

Check For Moisture in Air Tube

I posted a long reply to someone else with similar problem as did I. I found my problem was moisture in the airline from the compressor. Since cleaning and drying and periodically checking for moisture in line, I've not had a problem and am able to keep an arc.

[paulmac]

I have the box store Hobart plasma cutter with on board compressor. If I am cutting 18 or 20ga cold rolled (new), no problem. If I attempt to cut metal on the old car, it is a real chore. I always grind away rust to establish a good ground. I have the same electrical set up for on vehicle cutting as I do on new cold rolled 18 or 20ga. And I use the supplied stand off, and have replaced consumables. I can cut for a few seconds, then the flame goes out, then wait for the compressor to cool down the tip. A pain.

I recently viewed a video where they were cutting up old rusty cars and truck with an Eastwood plasma cutter. They clamped the ground on any old spot they wanted to and went to town cutting away through rusty old vehicle metal. I paid way more for my Hobart that they charge for the Eastwood, why is my Hobart so touchy on metal cutting? Good ground, good power supply, but boy oh boy flame out every few minutes and then wait for the compressor to cool down before you can resume "trying " to cut. BTW,they were using a long extension cord to power the Eastwood. What is going on here? Did I just throw away my money? I have a new Miller Mig Welder and I simply love it. I have been told that Hobart is made by Miller or at least uses Miller parts. That is why I purchased Hobart. Miller. I have a notion to order the Eastwood, and if it does what it did in that video, Hobart, you have a problem.

Ready for any suggestions.

[Dale M.]

What is actual model number of Cutter.... "Box store" could be any plasma cutter Hobart makes depending on what "Box" Store" you purchased it from...

You keep referring to "compressor cool down"... Exactly what do you mean?....... Are you having a issue with compressor?...

Is the "CUP" or "TEMP lights coming on? Or are you just having to wait a while before it starts to function again....

Have you tried all the trouble shooting procedures in manual?

[Hunter55]

I had a similar problem with my plasma cutter. I did everything you did as far as checking etc. etc. The problem turned out to be a break in the ground cable that was not visible. The cable somehow got pinched hard enough to break the wire but not the insulating coating. I found the break by rubbing my hand the length of the ground cable and "wah lah" there it was. Peeled off enough covering to make a repair, recovered with electricians tape and all is well.

[MAC702]

I think the "compressor cool down" is the torch post-flow. I also don't think you have to wait for it to finish before starting the next cut. Try it and see.

I'm leaning toward the material isn't clean enough for a plasma cutter to be as practical. You may have to go much more slowly to maintain good conductivity.

It's not just the work clamp that needs a good connection, but every part of the cutting path wants to be clean as well. Plasma arcs are far less tolerant than welding arcs.

What models Hobart and Eastwood are you comparing?