prepman
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You're so sophisticate...wish I woz....
- Thread starter conor1n
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AVI_8
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A 3 HP compressor will give you around 9 CFM, FAD and around 14 CFM displacement.
An air fed mask will require around 5-9 FAD dependant on mask, to run Both a mask and spray gun will normally require a big compressor 3 phase, or a single phase tandem compressor, or 2 compressors which would generally be linked to the same outlet and go through the 3 stage air filtration system providing filtered air to the gun and mask ….. in an ideal world.
An air fed mask will require around 5-9 FAD dependant on mask, to run Both a mask and spray gun will normally require a big compressor 3 phase, or a single phase tandem compressor, or 2 compressors which would generally be linked to the same outlet and go through the 3 stage air filtration system providing filtered air to the gun and mask ….. in an ideal world.
conor1n
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Ok guys thanks a lot for all the input here..
We are getting there. I was lucky enough to recently find a great deal on DoneDeal (Irish Gumtree..). I got this Shamal 3HP 200Ltr unit (RRP €830) for €400 .. it was basically new. Only a teaspoon came out of the drain tap.
I have also installed my cooler/drier on the wall beside it. Here is my current setup.
Here are some notes on changes I would like to make:
* The black hose is 2metres, but is only 1/4" which was made incorrectly at the shop. I need to return it to them as I wanted 3/8".
* I need secure the connector at the output of the copper to the yellow line so that when I tug at it, it doesn't damage the copper.
* I think the ball valve at the output side of the copper is redundant (what was I thinking) and would be better at the regulator end of black hose. (replaced with a smaller unit)
* Between copper and yellow line, I will add a coalescing filter+ regulator. Is a filter like this OK for general purposes and spray painting? Is that a coalescing filter?
* The yellow hose keeps kinking too, so I think I might add a swivel connection on the other side of filter.
* Is the regulator at the tank a good position? I guess it is?
* Would I need to get a new air hose for spraying? Wouldn't there be oil in the yellow one below as it was never filtered up to now? Or would it be safe?
* While I know there isn't the optimum number of drops on the copper setup, it does remove moisture and cool the air, so I am sure it is being effective. It should tee up the filter to remove the final amount of moisture?
What do you think?
We are getting there. I was lucky enough to recently find a great deal on DoneDeal (Irish Gumtree..). I got this Shamal 3HP 200Ltr unit (RRP €830) for €400 .. it was basically new. Only a teaspoon came out of the drain tap.
I have also installed my cooler/drier on the wall beside it. Here is my current setup.
Here are some notes on changes I would like to make:
* The black hose is 2metres, but is only 1/4" which was made incorrectly at the shop. I need to return it to them as I wanted 3/8".
* I need secure the connector at the output of the copper to the yellow line so that when I tug at it, it doesn't damage the copper.
* I think the ball valve at the output side of the copper is redundant (what was I thinking) and would be better at the regulator end of black hose. (replaced with a smaller unit)
* Between copper and yellow line, I will add a coalescing filter+ regulator. Is a filter like this OK for general purposes and spray painting? Is that a coalescing filter?
* The yellow hose keeps kinking too, so I think I might add a swivel connection on the other side of filter.
* Is the regulator at the tank a good position? I guess it is?
* Would I need to get a new air hose for spraying? Wouldn't there be oil in the yellow one below as it was never filtered up to now? Or would it be safe?
* While I know there isn't the optimum number of drops on the copper setup, it does remove moisture and cool the air, so I am sure it is being effective. It should tee up the filter to remove the final amount of moisture?
What do you think?
AVI_8
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I would, and make sure it’s rubber, some of the shiny coloured hoses have silicone in them which would cause problems.
brightspark
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if your going to use air tools you want a min of 10mm bore flexible pipe i use 15mm . get a half inch bsp seperator regulator and fit it on to the end of your tank. there will be a good loss of cfm through the smaller bore pipe
conor1n
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Ok. So at the moment all the hose is 3/8" = 9.5mm. The fittings are 1/4" .. (i'll be replacing the 1/4" hose).
Why would I fit the regulator to the tank side and not after the copper appliance?
brightspark
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because the one fitted that came with the comp is very restrictive. and small bore . i run at tank pressure and fit the reg seperator on the end of the hose and just short leads out of that to the tools or spraygun
conor1n
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Ok. I hear you.
What kind of Filter/Regulator do you use on your hose then? Is the inline filter coalescing. Are regulator filters coalescing or what?
brightspark
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just use half inch norgren filters picked up second hand. the blast pots i just use cheap machine mart ones or whatever turns up cheap
This is nonscence If you connect two compressor air tanks together ONE WILL START THE OTHER WILL NOT In practice just running on one pump. Buy a bigger compressor.
qwakers
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of course that wont happen, if the cutouts are at roughly the same pressure they will both come on at the same time.
if one is set lower than the other the first will come on until the pressure drops below the second pressure cutoff and then that compressor will come on too.
ive done this loads of times.
if one is set lower than the other the first will come on until the pressure drops below the second pressure cutoff and then that compressor will come on too.
ive done this loads of times.
AVI_8
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A one way check valve should be installed on the compressors
Ideally the cut in pressure will be adjusted so they are both as equal as possible though one will always be the master and one the slave.
The one way check valve ensures that the master (the one that cuts in first) is not pressurising the slave, the slave will then cut in when the pressure reduces.
So no not nonsense at all.
Munkul
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It's very easy. Picture a large set pressure difference.
If say one compressor is set to cut in at 95psi, and the other is set to cut in at 90 PSI, and the cut-out pressure of 120psi. They are both linked without any valves...
You start using air. The system pressure drops to 95 psi, and this one cuts in. All well and good.
If you're using more air than the first compressor can supply, the system pressure will carry on dropping.
Once it gets to 90 psi, the 2nd compressor cuts in as well. Now you have both running trying to boost back up to the cut-out pressure of 120psi.
If you are using less air than the two comps supply, they will both reach the 120psi at similar (although not exact times) and cut out.
Simple. No need for check valves.
In practice whatever the setpoints are on the compressors as standard will be fine. As long as they can both supply you more than you need, happy days.
If say one compressor is set to cut in at 95psi, and the other is set to cut in at 90 PSI, and the cut-out pressure of 120psi. They are both linked without any valves...
You start using air. The system pressure drops to 95 psi, and this one cuts in. All well and good.
If you're using more air than the first compressor can supply, the system pressure will carry on dropping.
Once it gets to 90 psi, the 2nd compressor cuts in as well. Now you have both running trying to boost back up to the cut-out pressure of 120psi.
If you are using less air than the two comps supply, they will both reach the 120psi at similar (although not exact times) and cut out.
Simple. No need for check valves.
In practice whatever the setpoints are on the compressors as standard will be fine. As long as they can both supply you more than you need, happy days.
Would not worry bout that IT WO'NT. One will run the other not at all
Pete.
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If the demand is greater than the one running compressor can supply (and let's face it, there's no other reason to have two linked), sooner or later the second one will start up.
Why are you being so pig headed when several people have explained exactly how it will work?
My self & several other members have ran 2 compressors siamesed together mainly because we either simply cannot afford a big compressor or do not have the space.
Where I used to work we had 2 screw air compressors running into the same line, the 2nd came on when the demand was high.
Similarly we had 3 refrigeration compressors all running into the same line, with the 2nd & 3rd starting on demand.
Both systems operated on pressure switches, each set at different pressures.
