Oddball question for the mechanically inclined.

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I am in the process of acquiring a nice lil ol shorthood. It is rough and ugly on the outside but runs like a champ - and I plan to leave it just the way it is, mostly (theft deterrent - scare em away with the rust).Heres my question in a long drawn out nutshell...Because I am cheap I have been trying to avoid coming up with an AC generator to throw on the trailer with my welder - DC power tools are one option I know, but not the most economical.Today while leaving a cafe I see what MIGHT be the solution to my problems... in the back of an El Camino of all things.  There sat an old no name generator and coming from between the engine and gen-set was a v-belt, connecting it to a compressor which was tied into a tank down at the tailgate.  While standing there admiring this monstrosity the elderly owner came out and in spanglish explained he was a painter,  and that he had built this contraption when the engine on his flea-market compressor had chunked a rod.  He went on to show me that he had a 125 psi safety valve screwed into the tank as a regulator (since the compressor was direct drive - no pressure switch).With the perfectly serviceable electric starter on my Lincoln doing what it should, the crank start stub is reduced to male porcine mammary status, as long as the starter works.Would it be feasible to add a pulley to that stub and connect it to a compressor to run air tools (which I already have 3 times what I need and half of what I want) adding a 12vdc clutch to the compressor side tied into a pressure switch on the tank?Does the welder have the spare horsepower to pull it without compromising amperage? With the right pulley ratio I can manage the RPM's on the compressor, make sure that the high idle/load speed is still below max rating.(F162 motor I think, but Im just getting into this rusty old lincoln addiction so not 100 percent sure)And to tie it all together on the economics angle, I already have an air tank and an old compressor with a seized B&S 5 horse  sitting on it. All I would have to buy would be the clutch and belt, if i need a different sized pulley I can turn one out - plenty of stock and a good lathe and mill.
Reply:your in luck , just so happens , my grandfather I built almost what your doing several years ago ,, heres what what happened  ,,, the draw on the main generator was to much , it would drop the output too low to maintain a good arc , BUT we discovered that if you only use one at a time , it works pretty good , , my grandfather later rigged a 12 volt ac compressor clutch to it and switched it to release when the welder was in use , and that eliminated the problem ,,
Reply:would be interesting to see how it was wired up, maybe 2 switches one for pressure i.e. demand, from there to the welder - not sure how to tie that in.  But have it rigged so both would have to be tripped to get current to the clutch to engage it. That way it would only charge the tank as needed but not while welding...Anymore suggestions?
Reply:[QUOTE=SRO1911;445294]With the perfectly serviceable electric starter on my Lincoln doing what it should, the crank start stub is reduced to male porcine mammary status, as long as the starter works.thanks     thats a new one for me..i always thought useless was teats on a frog..and  good luck on the retrofit, good thinkin..
Reply:Originally Posted by SRO1911...   reduced to male porcine mammary status ...
Reply:unloader and relief valve are two differnet things.
Reply:If you want air, try using an a/c compressor of a car. I have used the York and the sanden compressor on my Jeep with great results. I made brackets to mount them on the engine like a generator, used a pressure switch wired to the electric clutch to pressurize a small tank. I use it to run air lockers.pump up tires and run air tools like impact wrenches. If interested check out KILBY engineering. Might by KILBEY.JIM
Reply:Thought about using an A/C compressor thinking it would be lower torque/higher rpm and I could ramp the rpms to it way up with the right size pulleys.  (I've got a few of those laying around as well)  But what kind of realistic CFM and PSI can you get out of one?Would it be able to handle say, a 9 inch topcat grinder? - I would say thats the heaviest thing I would run, neither my die grinders or drills draw that kind of load and I have moved my needle scalers to the teats on a boar hawg category as well at least for work outside the shop.All of this is with either a 30 or 45 gallon tank (those are what  have that will fit comfortably on the trailer) ?
Reply:A 9 inch diameter air grinder?That's going to be a LOT of air demand.  Waaaaay more than a 1/4 inch die grinder.  A 1/4 inch die grinder uses air at about 20-25 fmm continuous (so in 'burst' mode the makers will sometimes call it 4-5 cfm air usage.  Riiiight.    )OK, so I check I-R.  Their 'big' angle air grinder (G3A120RP105) running 12,000 RPM no-load and a 5 inch guard and wheel sucks down air at 55 CFM at load.No way will a 'little' air compressor satisfy that thing.  The best laid schemes ... Gang oft agley ...
Reply:Cheap:To save gas I tow my truck around rather than drive itEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:ever think of running a york or sanden straight off the truck engine like jeepinjim said? a pressure switch could control the clutch & a tank can be mounted under the truck to the frame... you'l always be aired up & you can then run both at the same time no problem... just a thought...miller 330a bp TIGmiller dynasty 200DX TIGmillermatic 185 MIGthermal dynamics cutmaster 101 plasma cuttersnap-on YA5550 plasma cutterhypertherm powermax 30 plasma cutterbaileigh CS225 cold sawetc....
Reply:I am definitely planning on hooking up another A/C compressor under the hood of the pickup, just for grins.But that would defeat the self-contained trailer concept.  I just looked up the specs on the topcat's - 9in = 25cfm free 60 cfm max load. (seldom used) 4 in. = 25cfm max load (used a lot), die grinder = 35cfm max load, chopsaw = 75cfm max load (will a makita or dewalt run on dc?) , and last but not least and somwhat suprising 3/4 in drill = 35cfm max.I guess looking at it like that, finding a separate engine for my compressor isn't such a bad idea. Thanks for all the input, I know pneumatics are not the most common thing on a mobile rig but you got to go with what you've got.  I'm just getting this together for me, I don't intend to work it all that much right now I've got a pair of good guys in the shop for all of our outcall stuff, they supply the rigs - we keep em busy. I'm just trying to 'round things out' - I hook out with the welders  whenever I can to get a little practice, and when the welders are in the shop I try and get them at least familiar with machining.