Air mask CFM requirments

[rtbcomp]

Just because you pump 40 psi into the mask doesn't mean the mask pressurises to 40 psi. It doesn't, the air escapes and keeps the pressure down. You need the high pressure to shift the volume through an airline.

You could always use an oil-less diaphram compressor, but it would need a 100% duty cycle. You'll still need a water trap though.

You need sufficient flow to keep the mask at a resonable pressure and you still need a good seal round your face, otherwise polluted air could still get inside due to turbulence.

 

[eil]

Just going back to the belt mounted motor type JK was taking about and the link I posted about the one on e bay, I don't think that one is right for spraying 2K and its just for dust, any idea who produces these types and are they cost effective against the compressor air fed types?. It just seems there is no getting away from the fact that if you do a lot of spraying you have to go the filtered compressed air types.

 

[jaykay]

i did get a american regular mask that said it was ok with 2k.but had to change filters every use.i got that mask from nu-agane in bedford. seemed to work fine.well i ain't dead.

 

[eil]

Ive got me one of these
http://www.regency-uk.com/html/scott_full___half.html
but its flipin hot in it, but at least I aint dead with using it.......... Yet!

 

[Bullyterrier]

The 3m 4277 masks are ok for organic, in-organic vapour, particle and acid vapour. They are ok for 2k apparently, why the 3m disposables aren't recommended for 2k is you can't tell when they are getting to the end of their life...not working as they should. A mate who is a sprayer was telling me they are ok, supposed to be changed every month, but he said if you don't use them much and keep them sealed in their bags they will keep longer.
I was talking to a sprayer over here in France and he doesn't use any mask in the booth, vacuum below spray booth floor, and fans above so the air is moved out very quickly (it was a smart looking booth), he said they would wear a 3m disposable if painting the interior of a car!

 

[richweld]

The spec for Wilson Airvisor air fed mask is:

Maximum air flow rate in hood 220l/min = 7.8cfm
Operating pressure 2.3 -7 bar = 35psi - 102psi

The pressure to the mask is fixed by the regulator in the carbon filter. That cannot be altered. You fix a regulator to the outlet that goes to the spray gun to control spray pressure.

 

[deltacharlie26]

Interestingly I took an old Willson filter to pieces to see what was inside. There is no regulator just activated carbon with a fine prefilter stopping the carbon granules from falling out. They seem to work best at 50 psi. My compressor puts out just over 7cfm and it works fine at this consumption.

 

[richweld]

The carbon filter must control the pressure to the mask in some way. The filter will reduce the pressure. I assume if you set your system pressure anywhere between 35 - 102 psi, the mask will work OK.

 

[eric_knapper]

Interestingly I took an old Willson filter to pieces to see what was inside. There is no regulator just activated carbon with a fine prefilter stopping the carbon granules from falling out. They seem to work best at 50 psi. My compressor puts out just over 7cfm and it works fine at this consumption.

Thanks for the info Deltacharlie, the compressor I have access to outputs 8cfm but It only has a 50L tank what size of tank does your compressor have that you use to feed the Wilson mask as richweld specs for it says that it uses about 220L/min. My local tool shop has an ex display 100L air reciever with new certificate for £80 would that plus my compressor be upto the job?

 

[deltacharlie26]

My tank is 100L and with the regulator set at 50psi the compressor is running more or less all the time once the excess is used up. I use it when sandblasting outside so I like a good flow of air. I think you could run it at a lower PSI but if you are moving about and its warm then it does become uncomfortable at lower settings. If I was using the mask all the time, then a bigger compressor would be the answer. The bigger tanks help but eventually if you are taking out more than you are putting in the compressor is running all the time. If your compressor puts out a genuine 8CFM FAD then you have an excess of air so your compressor will cycle as required and will do the job, IMHO. If you are running a spraygun as well, then you will need a bigger compressor or wait while the tank tops up. My sandblaster is fed from a 100cfm Hydrovane but I use the smaller comp just for breathing air as it is remote from where I am working and set up just for that. Hope that helps.

 

[eric_knapper]

Yes I have my paint gun on a different system so it will only be used to supply the mask. I would be using it for about 10 minutes at a time maybe 15 for a larger part with about 15 minutes between each application. I don't have a FAD figure for the compressor so that will be lower than 8cfm listed for the compressor but it sounds like I should be ok with the extra receiver capacity added.

Anyone have a good supplier for the Willson masks.

Eric.

 

[deltacharlie26]

One on eb*y as we type