Modifying an air compressor

[crash]

I have a large 240v / 15amp air compressor aprox 300lpm of free air. It is about the largest you can get before going to 3phase power. I want MORE, as I run a sand blaster and some high volume air tools.

My thought was since you can get just the compressor pumps fairly cheap would be to get a 2nd compressor and run it off of my existing compressors motor in tandem. But I am unsure as to how to plumb it in - do I tee it in where the existing one is or would I be better off plumbing it into where the drain valve is (plumb it so to still have a drain).
The other concern I have is will this put too much strain on the motor.

[Homestar]

That would overload the motor in pretty short order. Why not get a second complete compressor and plumb both into a larger receiver tank? You can get these second hand at a reasonable price from time to time.

You would probably need to run it off a power point on a different circuit than the other one though.

[scarry]

You would need a much larger motor as you are doing double the work.

As said,two compressors are the go,run off different electrical circuits,depending on the current draw of each.

[crash]

Why not get a second complete compressor and plumb both into a larger receiver tank? You can get these second hand at a reasonable price from time to time.

You would probably need to run it off a power point on a different circuit than the other one though.

Been looking for a 2nd hand compressor but have not been able to find what I want. I have been looking at some of the petrol models - they seem to have bigger CFM ratings. Other problem is I do not have a 2nd 15amp circuit.

[Homestar]

I could always check to see if my mates still got his old diesel unit up for sale - 80CFM, works fine, needs some TLC and he wasn't asking the world for it last time I saw him, but not sure if he's moved it on yet.

[roverrescue]

Old
As in find at the tip old for nix
45kg gas cylinders make prime receiver tanks

yank the POL valve, run a 3/4" copper as a dropper with a valve and tee off that to you air system.

I have one mounted up in the rafters, with 3/4" plumbing I would go 2-4 more of them before buying a different compressor. Might take an eternity to fill but once it is filled it would push some air!

Oh and the dropper tube of 3/4" off a 45kg cylinder at 110psi does some serious dust cleaning on an air filter element!

S

[Blknight.aus]

you may not want to put the larger reciever in place.

depending on how much flow you need, simply plum up the second compressor (motor and pump assembly + electrics) to the one smaller tank. it gives you less reserve but it will come up quickly.

you will need to run it on 2 separate circuits and I'd goto the effort of ensuring that the cut in pressures are different so you dont wind up trying to start 2 15 amp compressors at the same time.

[crash]

depending on how much flow you need, simply plum up the second compressor (motor and pump assembly + electrics) to the one smaller tank. it gives you less reserve but it will come up quickly.
.

How is the best way to plumb them together?

[Blknight.aus]

depends on how they're set up but ID be guessing that you put a T piece on the fitting for the control switch and stick them both on the same outlet of the tank.

For the compressor outlets... depends on whast fittings you have on the tank the easy way is to just pick up the outlet from the one way check/dump valve and fit it onto a spare tank outlet.

if you dont have a spare tank outlet you can use the rear inspection bung, or Tpiece the existing fitting for the already mounted pump outlet.

[crash]

Another thought I had was going up to a 10 or 12mm hose diameter vs my current 8mm. Pressure would drop but you should get more volume. Just have to look at my hose connections where they screw in, and find out what my smallest diameter is.

[Aaron IIA]

You would actually get less pressure drop if you increased the diameter of the delivery pipe.

Aaron