Hobart Beta-Mig II repaired, now I need to sort the drive rolls.

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The other shop sent over an old Hobart Beta-Mig II for repair. I was told it didn't feed wire correctly. Upon inspection I found the main contactor was burned up. I suspected maybe it was working sporadically and due to weld/shop noise the user may not have noticed the contactor clapping. Someone had wired the input (480V single phase) using crimp on spade connectors. This created a lot of heat and eventually burned up L1 on the contactor. You. can't see the contact in the photo but it was completely smoked. I suspect the spade connector must have been arcing for quite a while. The lug was melted through. I thought about simply moving L1 to the un-used L2 contact, but L3 looked near death, so I ordered a new one. Thank you eBay! I checked the brushes on the feed drive motor, as I was certain they hadn't been serviced, but they looked good. Once the new contactor arrived and I installed it the machine appears to work properly.But the solid wire on the machine didn't appear to match knurled roll. I would have expected a smooth v-roll. The tensionior was adjusted full tight, which immediately told me something was wrong. So tonight I poked through the manual Hobart sent me (Spec S-6967-1). I'm thinking I need a roll 375649-1 (0.035) or 375649-2 (0.045).  I can't seem to find rolls online that match the numbers.Can anyone school me on the Beta-Mig II drive rolls? Anyone have correct part numbers? Will I have to make my own?I'm thinking this machine may have been setup for 0.052 or 0.0625, which would explain the need to clamp it down so hard to feed. I'll take the rolls and guide off tomorrow and see it I can divine what it's setup for.
Reply:Upon closer inspection I found the problem. The wire on the spool is 0.035 hard wire, the rolls are knurled two piece style, and the guides are 0.0625 (1/16). No wonder it didn't feed right. I don't see any numbers on the rolls other than the size markings. The guide number is HOBART 377941 and is marked 1/16.Looking at the manual it only lists input guide 377941 and 375655 for the output guide. So am I to assume the guides are 1/16th  regardless of the wire? The manual does list two shims under the output guide without callout on the drawing, 376024 -.005 Mylar, and 407075-3 -.005 Steel. Not sure where the shims go or if they are needed. I'm thinking the shims center the rolls. If you look in the second photo you can see a very thin washer behind the plastic roll dog.The output guide looks fairly worn. I suspect it's over sized.
Reply:https://www.ebay.com/itm/Thermal-Arc...wAAOSwyJVdMigWThese are the only drive rolls that you find on ebay.   Profax  does have 376246-002 V knurled kit with guide,377941- inlet guide and 375655 outlet guideThese are thermal arc for the Hefty suitcase.
Reply:Originally Posted by guajilloweld03These are the only drive rolls that you find on ebay.   Profax  does have 376246-002 V knurled kit with guide,377941- inlet guide and 375655 outlet guideThese are thermal arc for the Hefty suitcase.
Reply:if you think this style will work, I have what you need.. Have some short guides, but not the long ones. I had the Thermal-arc stuff that was all Hobart, but paid little attention to the old school Hobart beta rolls,etc... Looks like the center hole is smaller on the betamig.. Maybe a bushing to adapt to later stye? Depending on thickness on the old style stuff. Most of thermal ones run two rollers . top, and bottom pairshttps://www.ebay.com/itm/Thermal-Arc....c101195.m1851Last edited by Brand X; 03-24-2021 at 07:06 PM.Esab/Lorch ET-220iEsab 160i caddyThermal LM-200 Lincoln feedersThermal Pee-Wee 85sThermal 60i- 3phase /RPC powered (Beast)Thermal Drag-gun 35CINE 1500 Klutch 140i
Reply:Originally Posted by Brand Xif you think this style will work, I have what you need.. Have some short guides, but not the long ones. I had the Thermal-arc stuff that was all Hobart, but paid little attention to the old school Hobart beta rolls,etc... Looks like the center hole is smaller on the betamig.. Maybe a bushing to adapt to later stye? Depending on thickness on the old style stuff. Most of thermal ones run two rollers . top, and bottom pairs
Reply:I will post up some sizes /pics when I get a chance. I do remember the single driven bottom roll design.. I really have a pretty good set of drive rolls for the Hobart/Thermal stand alone feeders.I always liked the design and types available.Esab/Lorch ET-220iEsab 160i caddyThermal LM-200 Lincoln feedersThermal Pee-Wee 85sThermal 60i- 3phase /RPC powered (Beast)Thermal Drag-gun 35CINE 1500 Klutch 140i
Reply:Center holes is 1.00  outside dia is 1.6 inch and width is .565has a smooth top flat roller @ .024/.045  A smooth groove solid wire bottom roller at .024/.035.Two- .045 Knurled Two-3/64 rollerscouple of guidesIf they can work, then I will send them off. PM a address. Attached ImagesLast edited by Brand X; 03-25-2021 at 02:25 PM.Esab/Lorch ET-220iEsab 160i caddyThermal LM-200 Lincoln feedersThermal Pee-Wee 85sThermal 60i- 3phase /RPC powered (Beast)Thermal Drag-gun 35CINE 1500 Klutch 140i
Reply:Originally Posted by Brand XCenter holes is 1.00  outside dia is 1.6 inch and width is .565has a smooth top flat roller @ .024/.045  A smooth groove solid wire bottom roller at .024/.035.Two- .045 Knurled Two-3/64 rollerscouple of guidesIf they can work, then I will send them off. PM a address.