gas issue

[steae92]

hi all ive recently just got some little halfords co2/argon mix bottles for my sip migmate and there is no gas coming out of the torch. i put my ear next to it and couldn't hear anything. the migmate is a really old machine i got it second hand as i cant afford a new machine yet. so i really need to get this working.

i pulled the pipe off before the solenoid thing and gas was coming out of that but when i put it back on and pulled the second pipe off (after the solenoid) no gas was coming out when i flicked the torch trigger. so im thinking its the solenoid?

but i tried bypassing the solenoid (gas straight into the torch) and still no sign of gas coming out of the torch.

anyone got any ideas?

cheers in advance

 

[rtbcomp]

Can you hear/feel the solenoid click when you pull the trigger? Does the wire feed OK?

 

[steae92]

hi, wire feeds perfect i felt to see if it clicks and it doesn't click but i can hear something clicking when i press the trigger which im not sure if its that solenoid or not. ive just had a look at the regulator and there is a seal in the part that the bottle screws into and it looks nackered so im wondering if do they need to be at a certain pressure before the solenoid kicks in? when the gas is coming out of the regulator pipe when i pulled it off it didn't seem to be a lot of pressure behind it. it barley blew the hairs on my hand. although this is the first time ive messed with a mig so i dont know how much pressure its ment to be.

 

[rtbcomp]

The clicking will be the main contactor, it sounds like you may have got a duff solenoid, do you know how to use a voltmeter? If so you could check to see if there's a voltage feeding the solenoid.

I'm not sure whether that model has a mains solenoid or a low voltage one, so start on the top AC range of your meter and work down. Assume it's mains, so keep your fingers clear!

The solenoid should kick in regardless of pressure, but there may be some pressure loss across it. Is the regulator adjustable? If so it needs turning up to maximum.

 

[steae92]

yeah i know how to use a voltmeter i just dont have one to hand. do you think it would be to powerful to try a test bulb on?

there is 3 spade connector type fittings on the back of the solenoid but only 2 have wires on them leaving one spare. both the wires are black and im not sure if im correct but the both look like they are leading to earth. if this is the case then im missing a live. but i dint really want to strip the welder right down because im not the best person with electrics lol.

 

[rtbcomp]

I'd need the circuit diagram to answer that. I doubt that both will lead to earth, a test bulb would be OK if we knew what voltage we were looking for.

 

[madkayaker]

A 230v bulb would be ok ish to try to find the fault but a multimeter is less than £15 for a cheep one

 

[steae92]

i could probably borrow a meter off my mate. im going to strip the torch tonight and see if everything is in order in there as well. i will report back when i have checked everything

 

[steae92]

right ive ripped the torch apart and there is no regulator in the torch. its probably too old for that type of technology lol. it seems to be a straight through design. there is 2 wires in the torch one is red that go's to the trigger contact thing. and the other is white which doesn't seem to be connected to anything. there was no connector on the white one so i presume it has been like this for a while.

there is something i did notice. the wire liner seems to long. its pushing up against the thread for the torch neck. im wondering if this is restricting gas flow?

sorry my description is a bit crap im new to having welders in bits lol. i might take some pics later if that will help?

 

[rtbcomp]

Pics would help!

 

[steae92]

its ok now ive found the issue. the torch line is nackered there is no line in it for gas and the live wire for the torch trigger is all split open. does anyone know what sort of torch will fit a machine this old?

 

[rtbcomp]

Have you still got a problem with no gas coming out of the solenoid? If so and you need a new solenoid it may not be economical to repair this machine, given that it may not have been the best of the bunch even when it was new.

Otherwise the best repair would be to fit a Eurotorch conversion.

 

[BillJ]

I don't know if it is the same for very, very old Migmates but certainly from 6 or 7 years ago (when I bought mine) they do not have a solenoid. The gas valve is in the torch, operated by the trigger.

If this is the case then a Eurotorch conversion will require the addition of a solenoid and is probably not an economic solution.

A click from the torch is probably the microswitch.

As mentioned above, photos of the welder might help so we can identify it.

 

[zx9]

Your description of the torch sound just like the torch on my old (20+ years) Migmate 100 which I brought back into use this winter.
The trigger on the torch presses a bent metal contact against the metal into which screws the swan neck, only the red was connected with a push on spade connector, the circuit been completed by the main touch cable.
My gas tube was split inside the black outer tube that connects the torch to the welder I assume from been coiled around the machine too tightly for too many years.
I checked operation of the gas solenoid by pulling the gas pipe off the end of the torch lead (inside the welder) gas was coming out then I pressed the torch trigger in a constant stream, when reconnected the gas came out of the end of the swan neck as a sudden spurt and seemed to reduce instantly because it was been loosed inside the touch leads.

I had a replacement touch assembly ordered from Parweld as SIP no longer stock replacement parts for the older hobby welders with solenoid gas control.
I now have a very old Migmate 100 with a Parweld MB15 torch. Was it worth the effort? Well for about £60 I got my old welder up and running again, it has not been used that often over the last twenty years but I bet it has a much better build quality than the modern SIP welders.

 

[steae92]

Your description of the torch sound just like the torch on my old (20+ years) Migmate 100 which I brought back into use this winter.
The trigger on the torch presses a bent metal contact against the metal into which screws the swan neck, only the red was connected with a push on spade connector, the circuit been completed by the main touch cable.
My gas tube was split inside the black outer tube that connects the torch to the welder I assume from been coiled around the machine too tightly for too many years.
I checked operation of the gas solenoid by pulling the gas pipe off the end of the torch lead (inside the welder) gas was coming out then I pressed the torch trigger in a constant stream, when reconnected the gas came out of the end of the swan neck as a sudden spurt and seemed to reduce instantly because it was been loosed inside the touch leads.

I had a replacement touch assembly ordered from Parweld as SIP no longer stock replacement parts for the older hobby welders with solenoid gas control.
I now have a very old Migmate 100 with a Parweld MB15 torch. Was it worth the effort? Well for about £60 I got my old welder up and running again, it has not been used that often over the last twenty years but I bet it has a much better build quality than the modern SIP welders.

thats exactly right mate. i have been quite lucky my mate gave me a snap on welder to salvage the parts that i needed so now i have a snap on torch on it. its welding a treat now. cheers for all the replies