help - wire feed does not work

[Petew]

Hello,
I have an Oxford Mig company welder. It was made in about 1997 and I'm told they made good equipment, however they went out of business some years back.

I've only used this about 6 times so it's practically as new however now that I want to use it it's developed a fault; typical! The wire feed does not work at all. I've checked the torch and it does trigger properly. I put a meter on the connections to the PCB where the wire feed motor connects and that has a reading when triggered. Unfortunatelly I couldn't be sure about the wiring from the transformer so I couldn't put the motor directly on that to test it and as it's 24v I can't put it on a battery as I don't have one.

Can anyone suggest anything I might look at or any contacts for Mig repairers in/around Bucks (if poss). I've looked for local(ish) repariers on the net but without much success.

Thanks for looking.
Pete

 

[weldequip]

Which model is it?

 

[Petew]

Sorry, I'll have to check when I get home and answer this.

 

[Petew]

It a 165 Turbo Mig. Also has a badge saying 'Classic Welding Range'. I'm guessing from the serial number it was manufactured in 96. Thanks. Pete

 

[weldequip]

Sounds like the PCB mounted Relay to me. Can get it repaired for you but without physically testing the machine we are working blind & it may be something else.
weldequip

 

[Petew]

Thanks.

I've had a thought, it would be a good idea if I connect a couple of 12v batteries up and test the motor directly. I' d be surprised if that's gone wrong, however, if it was a relay I'd assumed I wouldn't get a reading on the PCB where the motor leads attach and I'm getting one when the trigger is pulled. But I don't know diddly squat about how welders work internally and I'm gratefull for your advice.

I realise it would be hard fixing this with only the PCB but it may be worth trying that first as sending the whole machine to and from you would be costly.

I'll look again this weekend and let you know how I get on and we can take it from there. Thanks for the reply.

 

[Petew]

I've done some more investigation.
I checked the PCB connections for the motor and they showed a reading of about 8 volts with the wire feed turned up to max, down to 0 volts with the feed at 0 (min). So that looked ok.
As the motor is marked up as 24 volts I put than on the motor directly and it nearly took off! I put 12v on and also 3 volts and from that I deduced it's working fine and the wire speed is obviously obtained by varying the volts to the motor. It seems that 8 volts or thereabout is all it needs for MAX speed for the wire feed.
So both looked ok, why wasn't it working? I put them both back together and tried and it worked this time. I was kinda hoping that the motor had maybe frozen as it hadn't been used for 2-3 years and the 24 volts had freed it. I did some test welding and after a while the wire feed stopped again.
Back with the meter and I found there is an intermittant fault that's stopping any volts from going to the connectors for the motor.
I can hear the relay working and as it's see-through I can see it and it looks ok but it does appear to sound slightly different when the wire feed is not working. It sound a bit quieter/tinier/lighter. Maybe it looks like it's working but isn't making proper contact.
I'll send you an email privately and arrange to send you the board if that's ok with you weldequip.
Regards
Pete

 

[weldequip]

Hi Pete,
Recieved the circuit board this morning thanks; I'll get it checked out for you & keep you posted.
weldequip

 

[Petew]

Received the repaired PCB and reinstalled it Saturday. It seems to work properly now. I need to put the machine to use to be sure, but it certainly feed a load of wire through without stopping so it's looking good.

I'm gratefuly for your help in getting this repaired and really glad I 'found' this forum I've read a lot of useful threads here and will continue to keep looking.

 

[andrewg1323]

ooh What sorta price do yo charge for repairs? i;ve got 2 machines here with faults on the PCB and i dunno where to start!

 

[weldequip]

Depends on the make & model of the machine, some smaller stuff is hardly worth repairing and you may aswell just go for a new board.
weldequip

 

[andrewg1323]

Ones a big Taskmaster thingy cant remember the model offhand and the others a little Nutool thingy but not a clue where i could get a replacement board!

 

[weldequip]

Can have a look at the Taskmaster one for you but the little Nu-Tool would not be worth doing.

 

[EVANS THE MUD]

Hi Ther ,iv Just Bought A Sip/cosmo 170 Gas/gasless The One On Wheels Which Will Hold The Big Bottle 145amp From Ebay 250 Hard Earned Quids Rrp 440 Avnt Welded Anything Yet But Got Loads To Do On My Landcruiser.and Now Iv Found This Site Bin Reading Loads About The Wire Feed N Speed Probs Oh Whoe Is Me Please Tell Me That I Havent Bought A Lemon (and Its Yellow) Thanks Evs.

 

[weldequip]

A decent price but treat the torch lead & wire feed like bone china! Keep it well serviced & you should be OK.
weldequip

 

[EVANS THE MUD]

Thanks Weldequip, I Shall Give It A Go And Let You No How We Get On .oh Yer Hi Everybody

 

[tracer]

i have a sealey super mig 170/1 and now have no wire feed.

what causes this?

when the trigger is pressed, sounds like the relay is clicking but the small wire feed wheel does not turn.

thanks

 

[tracer]

i got the wire feed sorted ,

its the wire speed that cannot be changed-