Adding a tank to a 12V portable compressor

[Dragster Racer]

We drag race. If we are only running the jr dragster for the day, often there is no reason to run the generator. But if we need compressed air, then we need to fire up the generator, then the compressor. We have a deep cycle battery for the trailer lights inside anyhow, so I figured why not try a 12V portable air compressor? Better yet, there is room between the frame crosses under the floor for a decent tank. I bought the 150 psi Harbor Freight pump, and my father in law salvaged an old air tank from a semi. I know I need a pressure switch which is on the way. I probably need to use a relay to protect that switch since the compressor draws up to 30 amps. A pop off valve isn't a bad idea for safety. And probably some sort of check valve. Anything I am missing?

 

[kbs2244]

Just running time of the compressor.
Check the CFM rating vs the size of the tank vs the pressure you want.
Too big a tank may run the pump to the melting point.

Oh, some kind of drain set up for the tank.
Some kind of remote linkage will let you blow it out at the end of the day.
That will drain the tank and lighten the weight of the trailer.

 

[Dragster Racer]

I need to make sure the original drain in the tank is down so I can drain it like you say. Initial fill will probably take a bit, but usage isn't that much cfm, so I think we will be ok. Maybe? 150 psi pump with 120 psi switch. It is maybe a 4 gallon tank, and the trailer is roughly 7000#'s, so I don't think I need to get too crazy about weight. I may be wrong though. I was thinking ball valve for turning off the air at the end of the day. A gauge of course.

 

[CNGsaves]

Also nothing stopping you from installing a larger air tank to the trailer for mobile source of air. Heck a 26 or 30 gal tank could be mounted in a cool way up on front of trailer or angled part of tongue. Think McGyver.

I envision a welded frame around tank that has standard 2"x2" square hitch connector so that you could remove air tank and snap it into hitch of a pickup and haul it where-ever you wanted. With square bottom of frame on air tank, you could strap it to a dolly and haul around.

Fill up the 30 gallon tank on trailer before you leave for races, and may never need to use compressor at track, or only when needed. Good luck !!

 

[kbs2244]

Compressed air is heavy.

 

[crewchief888]

when i was racing flat track back in the 80's,
all i had was a fully charged 5gal air tank, it was more than plenty of air for making pressure adjustments at the track.

i'm in the process of piecing together a similar 12v system to use in my off road truck, using 2 12v HF compressors and a small tank.

just havent been scrounging (aka dumpster diving) enough to find a suitable tank.

 

[crewchief888]

I use those water filled stainless steel fire extinguishers as tanks.
Easy to mount, has a shrade and a valve and a pressure gauge and the wide mouth ones let you hide stuff inside.

thats a good idea


i have a couple of them laying around.

i use them for cooling down/ cleaning muddy radiators.

 

[Dragster Racer]

This appears to be about a 10 gallon tank. The tank weighs a lot more than the air that goes in it does.
When we go to a multiple day race, we run out of air. We also use air in the bladders that go under the dragsters to keep them from bouncing in the trailer as well.
I have the tank.

 

[DpSyChO]

I have a buddy that tried the HF 12V compressor and 7 or 10 gal tank idea on a offroad rig to air back up when leaving the trail The pump lasted about three wheeling trips after being hooked up to the tank, I dont think the compressor is rated for the run time he was putting it through.
He ended up getting a York AC compressor and converting to air compressor, he can now run air tools on the trail if need be.
I took a different route, I went by the local fire and safety place and bought a used 20lb CO2 tank like used in soda machines then ordered a fixed regulator online, I think it is a 130#. I can air tires back up on the trail or take tank to the junk yard to run air tools.
Fill ups are fairly cheap, they always swap my empty out for a full so I dont have to worry about hydro testing. But it really ***** to be at the junk yard pulling parts and run out of air,,, errr CO2, I'm keeping my eye out for a used spare though.

 

[crewchief888]

as much as a larger tank would be nice,
i'm trying to stay down around 5gal or so, for just that reason.

my wheeler is a "trailer queen", i really dont need to air up after a trip.

one of us usually has a generator, a pancake compressor, and welder in the tow rigs anyway.

 

[Flexia]

Viair makes nice 12v compressors that are meant for this. They have no problem filling a 10 gallon tank to 200psi for years. They are used for air ride vehicle. I used to have 2 in my car.

 

[Dale1962]

http://www.instructables.com/id/Truck-on-board-air-compresor-tank/