Old hobart "simplified" welder (1 Viewer)

Joined
Nov 16, 2003
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Dixie co. Florida
Ran into a old WWII era engine driven Hobart arc welder, data plate says 300A @ 40v, driven by a 6 cyl flat head Chrysler picked it up for $100, if I can get it going it will be a steal, if not well its a sturdy trailer.

Supposedly it was used for pipe line welding back in the day, guy I bought it from has had it for 20 years ran until a few years ago had carb issues, we will see what time has done to it since then, motor is free so that is a start, I never seen such a simple engine,

anybody got any experience with anything like this? any chance I could find a schematic for the welder part of it?
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right side.jpg
data plate.jpg
 
Joined
Feb 6, 2002
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OC, CA
This looks like one of the generators Hobart sold as stand alone units that you could drive with any engine, rather than one of their later integrated units. These rely on residual magnetism of the field poles, so you may need to "flash" it to get it going after you get the motor running. They are good units and there isn't much to go wrong with them except the brushes and the contacts in the range switch.

Ask here for more info.
Weld Talk Message Board and Online Forum - Hobart Welders
 
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OC, CA
Here is a schematic for a Hobart G-261.

https://webfiles.uci.edu/cglabe/Photos/HobartG261scheme.pdf?uniq=1thsb

This is a later style with an exciter section in the generator, so I don't know if it is that much help. Yours is similar except it lacks the exciter section. The range selector switches in increasing numbers of field windings (1-4) while the fine range adjustment rheostat limits the current in the field windings.
 
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Dixie co. Florida
Pinhead thank you for the schematic, that actually seams to fit, the exciter drives the plugs (on my welder a single plug) the PO said it can drive some 115v motor driven tools that can also be driven with an equivalent DC ( I think 87v DC )


Having a bit of trouble finding a 6 volt battery to fit, its like a half battery long but very narrow, it is nestled in between the engine and the frame, right now I cannot even find a starting 6 volt battery at all of any size, all the 6 volt batteries I find are deep cycle,

I may convert to 12v, I hear you can reuse the 6 volt starter, the ignition coil and alternator would need to be swapped over, have a dead 77 dodge truck that I could use as a donor.

It has a hole in the radiator that leads to a drive part on the end of the crank, I assume this is for a hand crank? it did not come with the crank is that even worth perusing? something tells me hand cranking a 6 cylinder was a chore when it was new, much less 60 years later
 
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Joined
Sep 13, 2003
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Wichita, KS
Any change the 6v Red top Optima battery will fit? They are half the depth and not quite as wide as a standard 12v battery, same height though.

We have two 24v GPU units that look identical to the power unit on your trailer. The things are dinosours but work really well.
 
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Jul 18, 2010
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Ohio
WW2 1943 Hobart Welder

Hello Gang,
I just saw the Hobart Welder thread and that you might want be interested to see the 1943 US Army Hobart welder that I own. The Model of Welder is: GR-300-S
The welder with trailer weighs 4000LBS and the trailer is equipped with blackout Lights.
It has a Dodge 230CI Flathead 6 Cylinder Engine which is the same engine as the 1942 WC51 Dodge ¾ Ton Truck which is pulling it.
The welder in its original configuration and on its original trailer . I also have its original Hobart US Army Technical Manual. It Has a Brass Tag on Armature stating it was rebuilt in 1950 in Fulda Germany by the Karl Schmidt Generator Rebuilding Facility.I

Thanks!
Mike
mike@weldedparts.com
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Joined
Nov 16, 2003
Messages
6,045
Location
Dixie co. Florida
That thing is cherry!


same radiator, with hand crank hole, same top and base, unfortunately the PO of mine sold the "hobart bros" plaque,


I was wondering weather there were suppose to be sides on it, now I know. have not gotten a chance to mess with mine, too many projects.
 
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Mar 7, 2011
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GR300S Welder Oil Gauge on ePay

I see you guys have a vested interest in your GR300S Hobart welders. I purchased a parts lot that has an oil gauge specifically called out for a GR300S. It's new and still wrapped in cosmoline. I hate to solicit but I thought without divine intervention, chances are you wouldn't be searching for parts this week. Forgive me for searching you guys out.

WWII GR300S Hobart Welder Oil Gauge, NOS 1943 Military - eBay (item 260748571894 end time Mar-13-11 21:34:35 PDT)

Thanks in advance,
Mont
 

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