Possible DIY welder generator?

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Ok, so I was rearanging some stuff in the garage today and I discovered a lost treasure I obtained a couple years ago. As a side job I clean out forclosed homes for realitors. As a perk I get to save anything that interests me. Thats where I found this generator. It was mounted on a huge trailer with a big four cylender engine. The engine was locked up, water came out of the oil pan. The electrical box on the thing had been chewed up by rats. And the trailer frame was broken. But the generator itself looked salvagable.So my questions are, does any one know anything about this type of generator? Would it be worth it to build a new generator welder with it? If you have any electrical advice, it would be helpful as well. I have a friend thats an electrician, but he's a really busy guy.Here's the stats off the serial plate. G.E. Aircraft starter generator. Type: CM74,  SPLG: G.E. E510,   Speed:3700/7200 rpm,    Volts:30   Amps:400,      (unreadable):33-038-ac-7201,     MFR. NO.:2CM74815 (looks like the 5 might have been meant to replace the one at the end)   Ser. No.:2277069I don't even know if this was ment to be a welder generator. The guy that lived in the house I cleaned out was obviously a do it yourself kind of guy (right down to his light fixtures made of tincans). It apperantly work as a welder for him though. 400 amps! Think I'll use it as a dedicated Carbon Arc gouging machine.Sorry for the poor pic. I'll get a better one if you want. Attached Images
Reply:Oh yeah. For reference, it's about 2 feet long.
Reply:You might get some ideas by looking at this.:http://www.metalwebnews.com/informat...arc-welder.pdf
Reply:http://www.vintageprojects.com/metal...rc-welder.htmleasy answer...Lincoln Weldpak 100Miller Maxstar 150Cutmaster 82Victor OA torch set...somewhere around here...
Reply:Originally Posted by Grimm1Here's the stats off the serial plate. G.E. Aircraft starter generator.
Reply:Don't tempt me guys! The thought actually went through my head to try putting it in my car. It wouldn't work though. I have a tiny little Civic, there's no room for this thing under the hood, and I doubt the suspension could handle the weight for very long. One pot hole and my car would be toast. Though the wiring schematics are helpful. Thanks.
Reply:Nice find? Rebuild? That all depends on what condition the innards are in, bearings and brushes/commentators. You need to have a motor-generator shop look at it. 30 volts @ 400 amps. 30x400 = 12,000 watts. 745.7 watts/hp; 70% eff.12,000/745.7 = 16 hp.  16 hp / 0.7 = 23 hp. Lets make it an even 25 hp @ 3600 rpm to run.
Reply:Jets were started with compressed air by a -60.  It had a turbine engine that bleed air was used to inflate & power the starter.  The air hose was about 3" in diameter & had about 80psi.This would have been used for ground power and/or starting recip engines.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:The bearings spin easily enough. Could probably stand a good cleaning though. I plan on having my electrician friend look it over too, if I can nail his feet to the floor long enough. He repairs generators and electric motors and their controls. 25 horse power is about what I figured. Probably go larger so I can put an air compressor on it too. Mount the whole thing on a trailer probably.
Reply:Originally Posted by MarkBall2Jets were started with compressed air by a -60.  It had a turbine engine that bleed air was used to inflate & power the starter.  The air hose was about 3" in diameter & had about 80psi.This would have been used for ground power and/or starting recip engines.
Reply:Power is applied via the -60, but it's bleed air from the turbine in the -60 generator that provides the push through the starter.  It's just a mini turbo that spins the engine to about 10% power, then fuel & ignition source is applied.  If it lights off, it will continue to climb in RPM until about 65% which is idle.I remember that fire.  And yes, it was when the buss bar shorted & failed getting double power from the generators in the front of the engine & the ground cart.  I think that was an F-4B that launched the rocket.  There were several in the Air Force, but those were sidewinders that bounced down the runway.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:http://books.google.com/books?id=oeJ...age&q=&f=falsePhantom Engine Start Procedure...........Aardvark's Engine Start Procedure...........http://books.google.com/books?id=of0...age&q=&f=falseLast edited by MarkBall2; 03-15-2010 at 12:17 AM.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Hello from Canada eh   Have to add my 2 bits worth.  Been there, done that, no t shirt.  Purchased one of those from a farmer who had it on an old Oliver tractor.  I installed it under the hood of a late 70's Ford pick up.  Used the info from the old Pop mech mag.  I did a few mods at the stabilizer, a switch activated by the magnetic force when striking the arc to energize a choke pull-off and slow vacuum release would rev the engine up and hold for a bit for the next weld before coming back to idle.  It welded smooth and clocked 200 amps at high idle. Ran it with a serpentine type multi groove belt. Wish I had pics. Was a fun project, just we can!!!!   Fred
Reply:I may have an engine for this thing. I salvaged a decent looking mid 80's model Honda Goldwing from another house I cleaned out. First I have look the bike over good to see if I want to rebuild it or not. Got it just a few weeks ago and haven't had a chance to inspect it really good yet. Thats the trouble with salvaging some of this stuff, have to make a snap decision if I want to salvage some thing, or let the scrap metal guy take it. Sometimes the item is just garbage, sometimes it's a good piece of equipment.
Reply:Originally Posted by MarkBall2http://books.google.com/books?id=oeJ...age&q=&f=falsePhantom Engine Start Procedure...........
Reply:That is a starter/generator just like it says. I don't know what engine it came off of but many different type of aircraft use them both fixed wing and helicopters. Current is supplied to it and it acts like a starter. After the engine is started the starting current is shut off and then it used as a generator.Tough as nails and damn near as smart
Reply:Well I managed to show the plans you guys gave me to my electrician friend. He's very excited about helping me build a welder out of it. Unfortunetly he's burried in work untill at least the end of the month. I took a peak inside the generator. Clean as a whistle, carbon brushes look good, no visible damage. The bearings turn easily by hand, no awkward noises. I'm going to wait untill I can get his help befor I try any wiring though.In the mean time I'll check out the engine from the motorcycle I salvaged and see if it's any good. I'll start posting in the projects section once I get the engine figured out.
Reply:I'm wondering if that Gold Wing engine will have enough power at 3600 RPM?  I know it won't at 1800.It will be an interesting project, one I will follow.Duane, ya don't need no stinking Holiday Inn Express.......  Just a friendly pilot, toss yer butt in the back seat & away you go!MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Transit suggested 25 horse power, I'm fairly sure the engine will generate more than that. Newer models produce over 100 horse power. If it doesn't have the guts, or just plain doesn't work I'll just track down another engine.
Reply:Originally Posted by MarkBall2I'm wondering if that Gold Wing engine will have enough power at 3600 RPM?  I know it won't at 1800.
Reply:Not doubting the pony's in the Gold Wing engine, just at what RPM will it reach the horsepower to give smooth AC electrics?  AC needs 1800 or 3600 RPM under load.  The question is will the motor put out 25 horsepower at these RPM's?  That I don't know.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Originally Posted by MarkBall2Not doubting the pony's in the Gold Wing engine, just at what RPM will it reach the horsepower to give smooth AC electrics?  AC needs 1800 or 3600 RPM under load.  The question is will the motor put out 25 horsepower at these RPM's?  That I don't know.
Reply:The problem is that gas engines don’t have a flat hp vs. torque to rpm curve. You need to pick an rpm and see what the Hp/torque is at that point. I would suspect that any engine that will produce 75+ hp will do. You will also need a governor to keep the engine at a given rpm as the load [torque] changes.
Reply:While speaking of RPM there should be a data plate on the sarter/gen. Make sure that whatever you use to drive it is geared or down to spin the generator no faster than the data plate speed. Surplus City used to sell such starter/gen welder kits. They had some coils and what not to go with themto make them weld bet. Might want to see if they have anything left.Last edited by tresi; 03-21-2010 at 11:40 AM.Tough as nails and damn near as smart
Reply:Does the Honda not have a transmission ?Originally Posted by BlueweldersDoes the Honda not have a transmission ?
Reply:The transmition is built right into the engine block. It has a drive shaft to the rear wheel. My wife's uncle owns a bike shop so I'm going to see if I can enlist his help on my project. If the engine wont work for the project he should be able to help me track down another suitable one. The goldwing engine is just what I have on hand at the moment, but not what I'm limited to using.