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cuemaker
04-13-2010, 07:33 PM
I picked up a rather decent looking Hobart Handler 180 for $70.00

Problem is the wire wheels wont work. I put a length of wire in the tip, and it will arc, but no wheel action...

Suggestions?

http://i201.photobucket.com/albums/aa129/xringx/DSCN2338.jpg
http://i201.photobucket.com/albums/aa129/xringx/DSCN2340.jpg
http://i201.photobucket.com/albums/aa129/xringx/DSCN2342.jpg
http://i201.photobucket.com/albums/aa129/xringx/DSCN2343.jpg

macona
04-13-2010, 09:10 PM
First make sure the voltage range switch is not between positions. If not try the motor at each position. Check voltage from tip to ground. If the voltage range switch is bad the motor will not run.

Next check the voltage at the motor. Black and red leads.

There is a pretty good possibility that the bigger of the two relays is bad.

gda
04-13-2010, 09:11 PM
Standard troubleshooting: Put a volt meeter on the leads to the motor and see if juice is going to the motor. That should help narrow down to board or motor. (Don't zap yourself)

You may also want to post on the hobard welds forum or call hobart technical services.

wierdscience
04-13-2010, 09:37 PM
Could also be the leads going out to the switch on the whip,could also be the switch.

EddyCurr
04-13-2010, 10:36 PM
You may also want to post on the Hobart welds forum or call Hobart
technical services.Another possible resource is the Hobart section in
'Manufacturer Product Forums' on WeldingWeb.com.

.

terry_g
04-13-2010, 11:03 PM
If it will strike an arc then the whip and switch are okay. Like a previous poster suggested check for power to the motor. There is also a wire feed
rate control on the front of the welder that could be a problem should be easy to test with a multimeter. Is there a fuse anywhere on the unit? Maybe on the printed circuit board.

Terry

lunkenheimer
04-14-2010, 02:13 AM
First, kudos for great pics. Not often seen on the interwebs.
Second, $70 is a steal. Even if you put $100 into getting it running it's a steal.

Do the wheels turn, or not? Your problem could be the motor, the contactor/switch that runs the motor, the wiring, or the wheels not gripping the electrode wire. If you covered this, my apologies, I didn't see it.

macona
04-14-2010, 02:57 AM
The relay on the circuit board is a weak spot in the design. It switches the motor from drive to brake. When you let go of the trigger the relay releases and shorts the motor across those two big power resistors on the board. If one of the contacts gets welded in place it cant switch and nothing happens. Take the plastic end of a screwdriver and give it a good whack. It might knock it loose. It has worked before for me to isolate the problem.

The brake is needed to stop the wire as soon as you let go of the trigger. There is enough momentum in the motor armature to feed it.

dvbydt
04-14-2010, 06:21 AM
Another vote for the motor relay being the problem. Note also that it is, as far as I can see, set up for "gasless" wire. If you intend to use it with solid wire and gas, the polarity will have to be changed so that the torch is connected to the positive terminal and the earth clamp to the negative.

IanR

MrSleepy
04-14-2010, 07:10 AM
Those plastic housing wire feed units with the little Johnson style battery drill motor are always a pain.
I'd check for continuity through the motor in addition to what has already been mentioned.

Rob

dr pepper
04-14-2010, 08:32 AM
The circuit board at the top looks as though it controls the wirefeed motor, check it for fuses, blown ones, the 2 large ceramic items look like power resistors, you can check them with a meter set to read ohms, the value will be written on the side.
Another thing you can do is unplug the red and black wires that go to the wirefeed motor, and temporarily with a piece of wire connect these to a 9v battery, with the pressure roll backed off so theres no load on the motor, it should then turn, if not then you have a suspect motor, you can take them apart but they are really hard to sort, new ones are available, or you can check out surplus parts centres a similar one may be available they tend to be standard case sizes, an r/c model centre is a good place for dc motors they know their stuff on them.

UFO8MyCow
04-14-2010, 01:59 PM
The relay on the circuit board is a weak spot in the design. It switches the motor from drive to brake. When you let go of the trigger the relay releases and shorts the motor across those two big power resistors on the board. If one of the contacts gets welded in place it cant switch and nothing happens. Take the plastic end of a screwdriver and give it a good whack. It might knock it loose. It has worked before for me to isolate the problem.


I was at a friends shop this weekend and he had the same problem with the same welder and that is the solution we sued to fix it.

macona
04-14-2010, 03:48 PM
I dont think I have ever seen a failed motor on one of these.

UFO, I would order another relay if you can solder it in again. The relay will fail again. I just order them from Digi-key.

cuemaker
04-14-2010, 08:29 PM
I havent had time to do any playing, but I called Hobart and got the part number for the correct board, which is 238881... Suggested retail is $175.70.. Miller4less.com has it for $145.70

Still, 146 plus 70 for the machine makes for a cheap machine with a full roll of wire...

Hopefully I will get to play with things tomorrow..

Thanks for all your replies...

cuemaker
04-14-2010, 10:15 PM
I unplugged the motor from the main board and then hooked up an 9v battery, and the motor goes whiiiiirrrrrr.... bad board.. yeah!

Oh, i did test the motor with the unit on and the trigger pressed, but no juice to the motor..

Scishopguy
04-14-2010, 11:35 PM
Cuemaker...when you install the new board don't throw out the bad one, just order the bad part from Digikey, as was suggested, and put the repaired board on the shelf for the next go around. ;)

cuemaker
04-15-2010, 06:04 AM
I would love to do that, but i would need to learn how to test the board to see whats bad. Probably best for another thread..

UFO8MyCow
04-15-2010, 12:52 PM
if you tap on it and it starts working it will deffinatly be the relay. just order both relays from digikey wich will probablt cost less than $10 shipped and solder them in. beats the hell out of spending $170 on a new board to fix a $70 welder

macona
04-15-2010, 05:36 PM
Oh, its the relay alright...

cuemaker
04-15-2010, 07:52 PM
What does the relay look like? I am not much for electronics, but I know I could solder in the parts...

Black_Moons
04-15-2010, 09:00 PM
the relay is the big black cube(ish) part that has traces on the PCB right to the motor.

Likey labled with a volt and amp rating, and maybe a little schmatic detailing its contacts/pins.

macona
04-15-2010, 10:05 PM
Black and odd shaped. The smaller one controls the gas solenoid.

cuemaker
04-20-2010, 01:06 PM
New board in and the machine works...Very excited.. now I need to learn how to weld...