Unkl Ian
12-07-2003, 03:26 PM
This explains how to make a small,silent,compressor suitable
for airbrushing and cleaning parts from a refrigerator.
Any type of refrigerator,dehumidifier,air conditioner,etc
could be used.
COMPRESSED AIR CAN BE DANGEROUS.MAY CAUSE INJURY OR DEATH!
Make sure you understand what you are doing,and why.This is only a
guide.Guaranteed 5 feet or 5 seconds,which ever comes first.
If you kill yourself,don't call me.
You will need a compressor switch,WITH an unloading valve.An
adjustable switch would be first choice.It will allow you to decide at what
pressure the pump turns on an off.If you don't use a compressor switch,the
pump won't shut off and something WILL BREAK.Also need a 1 way check
valve,VERY important.
Look inside the refrigerator,the big black lump is the
compressor.There are 3 Copper tubes coming out of the compressor.One is
plugged,forget that one.The larger of the other 2 is the intake,it can be
cut off where convient.The smaller of the tubes is the pressure side.It
probably steps up to approx. 1/4" diameter after about 6".You need to cut
the 1/4" diameter tube,leaving approx 3/4" ,and install a T compression
fitting.Compression fittings are available where ever they sell plumbing
stuff.One side of the T goes to unloaderswitch,the check valve goes on the
other side of the T.Install the check valve so that air can come out of the
pump,and through the check valve,but can't go back in.Once the system is
pressurized,the pressure switch turns the pump off,and the unloader valve
releases the pressure upstream of the check valve.If you don't do it this
way,the compressor won't restart unless it has less than 20 psi in the
system.From the check valve I run the air through the small radiator that
came with the water cooler.It also came with a thermostatic switch that
controls a fan,when the pump gets too warm the fan draws air across the
pump and blows through the radiator.Exiting the radiator the air goes
through a T on the back of the compressor switch,and into the moisture trap
and regulator.The regulator controls the output pressure.The compressor
switch turns the pump off at 120 psi and turns it on at 80 psi or lower.
110 volts from the wall goes to one side of the compressor switch,the
2 wires from the compressor go to the other side of the switch.
And that's it.A small tank would't be a bad idea,I recently added
a large moisture trap after the radiator to act as a small tank.
A 150 psi pop off valve would be a good safety feature,it would
need to be installed before the regulator.If the compressor switch
sticks on,it will prevent something breaking.I think all the
real compressors have them.
Make sure your compressor switch has an unloader valve,
it looks like an air fitting on the side of the small black
switch box.And don't forget the check valve.
Any industrial supplier that sells pneumatics should have check
valves.Mine was 1/4" NPT female.
I don't know how long this type of compressor will last without
lubrication.They use oil in the Freon to lube the pump,I don't know how
critical this is.It may or may not be a problem.When you drain the Freon
make sure you flush the oil out of the system,or it will get in your
paint.I used Brake Kleen.Green Peace hates me.It might not last 100,000
miles,but it is QUIET and will deliver more than enough pressure,and
volume,for airbrushing,cleaning parts and inflating soft tires.
And how hard is it to find an old refrigerator? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif
Copyright Unkl Ian 2003
for airbrushing and cleaning parts from a refrigerator.
Any type of refrigerator,dehumidifier,air conditioner,etc
could be used.
COMPRESSED AIR CAN BE DANGEROUS.MAY CAUSE INJURY OR DEATH!
Make sure you understand what you are doing,and why.This is only a
guide.Guaranteed 5 feet or 5 seconds,which ever comes first.
If you kill yourself,don't call me.
You will need a compressor switch,WITH an unloading valve.An
adjustable switch would be first choice.It will allow you to decide at what
pressure the pump turns on an off.If you don't use a compressor switch,the
pump won't shut off and something WILL BREAK.Also need a 1 way check
valve,VERY important.
Look inside the refrigerator,the big black lump is the
compressor.There are 3 Copper tubes coming out of the compressor.One is
plugged,forget that one.The larger of the other 2 is the intake,it can be
cut off where convient.The smaller of the tubes is the pressure side.It
probably steps up to approx. 1/4" diameter after about 6".You need to cut
the 1/4" diameter tube,leaving approx 3/4" ,and install a T compression
fitting.Compression fittings are available where ever they sell plumbing
stuff.One side of the T goes to unloaderswitch,the check valve goes on the
other side of the T.Install the check valve so that air can come out of the
pump,and through the check valve,but can't go back in.Once the system is
pressurized,the pressure switch turns the pump off,and the unloader valve
releases the pressure upstream of the check valve.If you don't do it this
way,the compressor won't restart unless it has less than 20 psi in the
system.From the check valve I run the air through the small radiator that
came with the water cooler.It also came with a thermostatic switch that
controls a fan,when the pump gets too warm the fan draws air across the
pump and blows through the radiator.Exiting the radiator the air goes
through a T on the back of the compressor switch,and into the moisture trap
and regulator.The regulator controls the output pressure.The compressor
switch turns the pump off at 120 psi and turns it on at 80 psi or lower.
110 volts from the wall goes to one side of the compressor switch,the
2 wires from the compressor go to the other side of the switch.
And that's it.A small tank would't be a bad idea,I recently added
a large moisture trap after the radiator to act as a small tank.
A 150 psi pop off valve would be a good safety feature,it would
need to be installed before the regulator.If the compressor switch
sticks on,it will prevent something breaking.I think all the
real compressors have them.
Make sure your compressor switch has an unloader valve,
it looks like an air fitting on the side of the small black
switch box.And don't forget the check valve.
Any industrial supplier that sells pneumatics should have check
valves.Mine was 1/4" NPT female.
I don't know how long this type of compressor will last without
lubrication.They use oil in the Freon to lube the pump,I don't know how
critical this is.It may or may not be a problem.When you drain the Freon
make sure you flush the oil out of the system,or it will get in your
paint.I used Brake Kleen.Green Peace hates me.It might not last 100,000
miles,but it is QUIET and will deliver more than enough pressure,and
volume,for airbrushing,cleaning parts and inflating soft tires.
And how hard is it to find an old refrigerator? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif
Copyright Unkl Ian 2003