I have a Chicago (something) Plasma torch from Harbor Freight and it
keeps dying on me...you kind of get to rely upon the fun tools in the
shop!

The current issue is that it will spark the pilot arc but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...I cannot find anything about the schematics
for it and I'm tired of taking it in for 4 weeks to get a $20 part fix
and a $80 labor bill.

These things have to be simple enough...just need some diagnostic
help.

I would also like to know about other "common" issues the I may
encounter and their fix.

DrO wrote:
I have a Chicago (something) Plasma torch from Harbor Freight and it
keeps dying on me...you kind of get to rely upon the fun tools in the
shop!

The current issue is that it will spark the pilot arc but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...I cannot find anything about the schematics
for it and I'm tired of taking it in for 4 weeks to get a $20 part fix
and a $80 labor bill.

If you put a daub of fingernail polish on
all the parts, you'll know the one that they
replace.

"DrO" wrote: (clip) The current issue is that it will spark the pilot arc
but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...
^^^^^^^^^^^^^^^^^^
You ARE aware, I hope, that the electrode and nozzle on the torch are
consumable. Have you examined/replaced those? If the orifice in the nozzle
gets too large, it will stop working. The electrode (on mine it's a steel
tip with spiral grooves around it) burns back as it is used. Eventually, it
starts acting the way you describe.

Even if those are not the cause of your present problem, you need to have
spares on hand.

Jim Stewart wrote:
DrO wrote:
I have a Chicago (something) Plasma torch from Harbor Freight and it
keeps dying on me...you kind of get to rely upon the fun tools in the
shop!

The current issue is that it will spark the pilot arc but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...I cannot find anything about the schematics
for it and I'm tired of taking it in for 4 weeks to get a $20 part fix
and a $80 labor bill.

If you put a daub of fingernail polish on
all the parts, you'll know the one that they
replace.
I don't know what torch your plasma has but mine has a Trafimet/Selco
S30 IIRC and I found out a design problem by debugging the workings when
it failed to play ball and I thought the electronics had failed . The
internal electrode is pushed back by the air pressure when the plasma
is initialised and the repeated impact of the consumable electrode on
the back housing upset the material causing it to pinch the retracting
shaft that the electrode was screwed into, eventually the pinch was
enough to prevent the electrode going back to the start position so the
electronics didn't see arc initiation and so no operation. Once I had
realised what the problem was a couple of quick passes with a small 3
corner scrapper sorted the burr and no further problems till the next
time but then I may know what the problem is.

On Aug 26, 3:41*pm, Jim Stewart wrote:
DrO wrote:
I have a Chicago (something)Plasmatorchfrom Harbor Freight and it
keeps dying on me...you kind of get to rely upon the fun tools in the
shop!

The current issue is that it will spark the pilot arc but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...I cannot find anything about the schematics
for it and I'm tired of taking it in for 4 weeks to get a $20 part fix
and a $80 labor bill.

If you put a daub of fingernail polish on
all the parts, you'll know the one that they
replace.

Funny you should say that...I did it the second time and I got ribbed
kind of hard as to the color of choice (don't use your kid's neon
pink)

On Aug 26, 5:51*pm, "Leo Lichtman"
wrote:
"DrO" wrote: *(clip) *The current issue is that it will spark the pilot arc

but not continue to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...

^^^^^^^^^^^^^^^^^^
You ARE aware, I hope, that the electrode and nozzle on thetorchare
consumable. *Have you examined/replaced those? *If the orifice in the nozzle
gets too large, it will stop working. *The electrode (on mine it's a steel
tip with spiral grooves around it) burns back as it is used. *Eventually, it
starts acting the way you describe.

Even if those are not the cause of your present problem, you need to have
spares on hand.

I change out two new nozzles and electrodes, thinking that was
it...still exhibits the same with new parts

On Aug 26, 7:05*pm, David Billington
wrote:
Jim Stewart wrote:
DrO wrote:
I have a Chicago (something)Plasmatorchfrom Harbor Freight and it
keeps dying on me...you kind of get to rely upon the fun tools in the
shop!

The current issue is that it will spark the pilot arc but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...I cannot find anything about the schematics
for it and I'm tired of taking it in for 4 weeks to get a $20 part fix
and a $80 labor bill.

If you put a daub of fingernail polish on
all the parts, you'll know the one that they
replace.

I don't know whattorchyourplasmahas but mine has a Trafimet/Selco
S30 IIRC and I found out a design problem by debugging the workings when
it failed to play ball and I thought the electronics had failed . The
internal electrode is pushed back by the air pressure when the *plasma
is initialised and the repeated impact of the consumable electrode on
the back housing upset the material causing it to pinch the retracting
shaft that the electrode was screwed into, eventually the pinch was
enough to prevent the electrode going back to the start position so the
electronics didn't see *arc initiation and so no operation. Once I had
realised what the problem was a couple of quick passes with a small 3
corner scrapper sorted the burr and no further problems till the next
time but then I may know what the problem is.

I found a picture of the air cooled electrode with a consumable
breakdown...(mine is the center consumable option)

http://www.plang-daichi.com/thai/pro...met_plasma.php

On what part in the picture did you find the flaw?

On Aug 26, 7:05*pm, David Billington
wrote:
Jim Stewart wrote:
DrO wrote:
I have a Chicago (something)Plasmatorchfrom Harbor Freight and it
keeps dying on me...you kind of get to rely upon the fun tools in the
shop!

The current issue is that it will spark the pilot arc but not continue
to burn (it's like it blows it out, or something doesn't cycle...bad
transistor or relay?)...I cannot find anything about the schematics
for it and I'm tired of taking it in for 4 weeks to get a $20 part fix
and a $80 labor bill.

If you put a daub of fingernail polish on
all the parts, you'll know the one that they
replace.

I don't know whattorchyourplasmahas but mine has a Trafimet/Selco
S30 IIRC and I found out a design problem by debugging the workings when
it failed to play ball and I thought the electronics had failed . The
internal electrode is pushed back by the air pressure when the *plasma
is initialised and the repeated impact of the consumable electrode on
the back housing upset the material causing it to pinch the retracting
shaft that the electrode was screwed into, eventually the pinch was
enough to prevent the electrode going back to the start position so the
electronics didn't see *arc initiation and so no operation. Once I had
realised what the problem was a couple of quick passes with a small 3
corner scrapper sorted the burr and no further problems till the next
time but then I may know what the problem is.

the electrode PN is ERGOCUT S 45

Well, I'll say what everybody is thinking: you got what you paid for.
Good luck, but keep your expectations low.

Bob

--
Nota for President

On Aug 27, 10:31*am, Bob Engelhardt wrote:
Well, I'll say what everybody is thinking: *you got what you paid for.
Good luck, but keep your expectations low.

Bob

--
Nota for President

LOL, yah I know...but wife will have fit when I show up with the
Miller Bobcat! WHERE DID YOU GET THE MONEY FOR THAT! Women can be so
funny at times.

That is why I don't buy JET tools anymore...unless I repaint them
black. She saw the shiney white thing in the middle of the garage one
day after spending a $100 on garage saleing for plastic lawn ornaments
and had the never to yell at me about my 15th saw purchase...96 cent
cans of black paint from Walmart...I buy them by the case

This my sound simple. But have you made sure your ground cable is good.
My cheapy does what you describe if and when I forget to clip the ground
lead on.






DrO wrote:
On Aug 27, 10:31 am, Bob Engelhardt wrote:
Well, I'll say what everybody is thinking: you got what you paid for.
Good luck, but keep your expectations low.

Bob

--
Nota for President

LOL, yah I know...but wife will have fit when I show up with the
Miller Bobcat! WHERE DID YOU GET THE MONEY FOR THAT! Women can be so
funny at times.

That is why I don't buy JET tools anymore...unless I repaint them
black. She saw the shiney white thing in the middle of the garage one
day after spending a $100 on garage saleing for plastic lawn ornaments
and had the never to yell at me about my 15th saw purchase...96 cent
cans of black paint from Walmart...I buy them by the case