Thread: 12v compressors.

good reason.

Good reason.

so far its got about an hours worth of run time for various tests and the total rounded costs are as follows.

second hand 12v 2.25 startermotor nada (I had one kicking around)
new 12v 100amp solenoid $15
cable and connectors $15 (some parts were leftovers and the clamps are off of an old set of jumperleads)
second hand compressor control unit nada (came on a 240v compressor that came free with fozzy)
Steel for fabrication $30ish including all the bolts and the leftover offcuts
2x large hose clamps $10
various air fittings $20
second hand aircon compressor (Nada TY AULRO)
out of date Gas bottle (nada again I had one)

so for $90 odd you can go buy



or for that and a little elbow grease you could produce



That monstrosity... which sucks about 70 amps and pushes enough air to run a rattle gun


ITs bare bones but it works just like a real compressor....

All it needs now is a safety cage for the belt (probabley not gunna happen) and the safety relief valve.

given where Im planning on mounting it The cage isnt a big priority and just for poops and giggles Ive run it in full idiot mode with just the compressor and the gauge on trying to blow something up after 10 minutes the gauge was just shy of pegged and not moving.

Since Ive gotten it this far Ive managed to get a slight leak on one of the fittings so Im not stressed about leaving it fully charged and the sun heating it till it bursts, it leaks from 140psi-0 in about 5 minutes.

Looks great and would be a fun project. Wondering about the safety of the LPG tank. Would think that LPG is nowhere near the 140 psi that you are playing with but I expect that the tank design is probably way over engineered for LPG anyway ? For a hose or fitting to blow at 140 psi no big deal but if a tank went there would be real potential for grievous bodily harm.

Ignore my previous post, talking through my A.., just looked up the data. LPG at 100 deg F is about 175 psi so the LPG tank should be just perfect.

If you have used the original gas bottle fitting/s it will have a 250 PSI relief valve there as standard.
The bottle is made - originally- to take around 400 psi. before something gives.
It doesn't look like you have welded on the barrel, so no problemo....

tested today.....

25 mins worth of tyres....

about 3 minutes to take 4 7.50r16's from 16psi-32.

the cheapy jumper cables that I sacraficed to make the battery connections from got very very un cold, the cable had started to get warm to the touch and the startermotor had also started to warm up, but I could still touch it.

Might bite the bullet and make the connections up out of some real wire instead of the piddly 70a stuff I started with along with permanantly mounting it to the vehicle.

I realise that sort of defeats the portability bit of it but Im not comforatble with setting fire to batteries if the current clamps go melty.

Just read the BBQ LPG bottle.
T.P. 33MPa
Which converts to about 2300 Psi.
The LPG bottle will be able to hold the pressure.

Aaron.