Wolf MIG 100 - feed gears needed

  1. Andy B New Member

    Long story short:
    Colleague: "Want a welder? - something wrong with the feed. Cluttering up the shed. I'll never use it. Otherwise its going to the tip."
    Me: "OK" - nothing ventured, etc.

    Result - Get it home, 2 minutes with a screwdriver to discover that one of the gears in the wire feed has lost all its teeth.
    I've seen all the negative comments on here about Wolf, no spares backup, etc - so I guess the only hope is if anyone has a similar scrapper due to a blown circuit board, or other fault.
    Otherwise, are there any bits that anyone else could use before I take it to the tip?
    Looking at the nozzle, I reckon its never seen more than 20 minutes use!
    It cost me nothing, so I haven't lost anything.

    Great forum by the way - glad I found it.

  2. GeorgeB pre-moderated

    London, UK
    Any chance you could post a photo of the wire feed module from the roller side? I think it may be the same as fitted to SIP welders and there are quite a few of those around, for sale at relatively low prices. A brand new wire feed module may be uneconomic to purchase.

    If it was mine, I'd carry out a few checks before taking matters further:

    1. With power applied do you get a welding type spark if you touch the torch to steel (as normal)? The wire won't advance but you should should get some indication of whether the high power side of things is working.

    2. Remove the wire feed motor from the gearbox. Does the motor spin when the torch button is pushed? If not, the PCB may be blown and that's not such good news, i.e if the motor does turn when 12V DC is applied directly, e.g. from a car battery.
  3. Wozzaaah

    Wozzaaah The wizard of woz Staff Member

    Wiltshire, UK
    That's good advice George, better to make sure the machine is a potential runner before throwing money at it. ;)
    A new hobby type gearbox/roller assembly is fairly cheap, about £30 delivered so providing the rest of the machine works ok then it may be worth a shot.
  4. GeorgeB pre-moderated

    London, UK
    Wow! I didn't realise they could be obtained at such a low price. Here are two further basic checks for anyone confident at digging around the middle of a piece of equipment carrying mains voltage electricity:

    1. Does approx 24v AC come out of the secondary winding of the transformer?
    It should. Transformer failure seems most unlikely.

    2. Does that change to approx 24v DV on the far side of the rectifier? If not, the rectifier may have blown and there will be no power supply to the PCB or wire feed motor, let alone provide the energy to produce a MIG arc weld.
  5. Andy B New Member

    Thanks for your replies.

    The motor runs fine and responds to the speed control.
    The donor told me that it does spark OK - just didn't feed. Will confirm as suggested before spending money.

    Previous user also managed to break the plastic mount (which is repairable) for the roller tension screw - so my guess is that the tension was too tight, the wire snagged somewhere and started bunching, then as it was too tight to slip on the feed pulley it just stripped the soft plastic gears instead.

    Will try to post a picture of the feed assembly this evening.
  6. BillJ Member