Hobart Beta Mig


Got a Hobart 250 amp Beta Mig from Craigs list for 100 bucks. Owner
had two, and didn't know why this one stopped working. Got it home and
it turns out it was just a broken wire on one of the control relays.
Now it seems to work fine, but the tap selector switch is very stiff
to turn, so I opened it up. The switch contacts look fine, but the
inside is coated with some type of grease which has gotten very
stiff. I guess the grease helped lube the switch to prevent corrosion
and keep it free moving. I've cleaned out the old grease and am
thinking of using Silicone spark plug contact grease or some thick Dow
Silicone "O" ring lube that I have. I'm hoping the wiping action of
the contacts will clear the contacts enough to allow good contact.
The old grease dissolved in solvent very quickly, so it don't think
the original grease was silicone based. The contacts are 1/8" thick by
3/4" wide bare copper strips in a housing about 6" diameter. Anyone
try this on switch contacts for low voltage? The Silicone is a bitch
to remove if this does not work..
Thanks
Reply to
oldjag
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Id suggest not using O ring grease..as it is indeed a bitch to remove. Most repair guys simply use a thin coating of moly di, white litium etc etc. All of which are easy to remove with a spritz can of cleaner. I generally tend to simply use a bit of standard grease gun grease and clean it up, then clean it again in 5-8 yrs and reapply.
Call any welding repair shop and ask em what to use if it bothers you.
Btw..the Beta Mig is a very nice old welder. Nice score!!!
Gunner
"I am for doing good to the poor, but I differ in opinion of the means. I think the best way of doing good to the poor, is not making them easy in poverty, but leading or driving them out of it. In my youth I travelled much, and I observed in different countries, that the more public provisions were made for the poor the less they provided for themselves, and of course became poorer. And, on the contrary, the less was done for them, the more they did for themselves, and became richer." -- Benjamin Franklin, /The Encouragement of Idleness/, 1766
Reply to
Gunner Asch
I have one of those and experienced similar issues with that tap switch some years ago. I guess I haven't dug into it as hard as you have, but I found, (on 9/11/2001 as a matter of fact) that all I had to do was to move the switch to one "edge" of the detent at about setting 5 or 6 to get it to work and haven't had any trouble since. I stongly suggest that you contact a local welding supply company in your area and ask them the grease question. The back room repair guys can be very helpful in things like this. One of the reasons for that is that they want to be around when and if you want to upgrade or get supplies. I'd also get a service manual. I don't remember now whether I had to buy mine or if I downloaded a pdf of it and printed it out. BTW, I had to jiggle and clean some contacts to get the wire feeder to work reliably, but that was back in 2001. The previous owner had stored it in a cold place up here in Wisconsin, a condensing environment. I now store it in a heated shop, where I NEVER allow a condensing environment. Silicon migrates a lot, I think. I'd avoid it in this application. Is that spark plug stuff really FOR contacts? I didn't think it was designed to be an electrical conductor at all. Someone please correct me if I'm wrong.
It sounds like you got a real good deal!!!!
Pete Stanaitis ---------------------
oldjag wrote:
Reply to
spaco
It's the stuff that you put on the pug boots and dist. cap towers before pushing on the rubber boots. Seem to be a lighter clear silicone grease. A lot of auto connectors use silicone grease now to help seal out moisture. Maybe I'll give a Hobart dealer a call tomorrow to see what they suggest. The newer machines don't use tap switches anymore so hopefully someone remembers what they used to used. Gunners comment is probably correct, the type of grease may not really be that important as long as it is cleaned out once in a while.
Reply to
oldjag
In article , oldjag wrote:
Do NOT use silicone grease on switch contacts. The sparks will crack the grease back down to silicon dioxide, otherwise known as sand, which will grind the contacts up.
Hydrocarbon greases crack to carbon and carbon dioxide, which are harmless.
Joe Gwinn
Reply to
Joseph Gwinn
AH!!!! Thanks Joe! Excellent explaination!
Gunner
"I am for doing good to the poor, but I differ in opinion of the means. I think the best way of doing good to the poor, is not making them easy in poverty, but leading or driving them out of it. In my youth I travelled much, and I observed in different countries, that the more public provisions were made for the poor the less they provided for themselves, and of course became poorer. And, on the contrary, the less was done for them, the more they did for themselves, and became richer." -- Benjamin Franklin, /The Encouragement of Idleness/, 1766
Reply to
Gunner Asch
That silicone dielectric grease is strictly for keeping HV from tracking, it's not lube and not for contacts. O-ring lube is generally meant for rubber to plastic or rubber to metal, not metal to metal. Somewhere I've got a tube of GE contact grease meant for big switch equipment that my dad rescued at one job site. So the right stuff is out there, if you can find it. It's amber in color and reminds me of the old-style wheel-bearing grease. Probably white lithium would work as well, it's non-conductive. Easy to get off, too.
Stan
Reply to
stans4

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