Hi Everyone
I am going to build my own airbrush compressor. I have a source for a motor from an appliance store here where I live once they have some extra old ones laying around. I have a friend who gave me the idea to build the tank out of the large PVC pipe instead of using a metal tank of some kind. To any of you airbrushers, does this actually sound like a good, reliable, safe way to make a tank. I know PVC can take quite a bit of pressure and there will be a motor shut off valve to control the pressure in the tank.
Any opinions or advice on this would be appreciated. I don't want to go to the effort and time doing it this way if it really isn't such a good idea in the end.

Thanks to everyone in advance for your input,
Wayne

I'm sure it would be possible to use PVC for your project. Just a couple of questions.
What schedule pipe are you looking at?
Will you be closing the ends off with threaded or solvent cemented caps?
What diameter pipe are you looking at using?
These questions will help you to determine your maximum safe operating psi. While I can give you working psi ratings, bare in mind that they are for WP - water pressure operating at a set temperature.

When it comes to the pipe - I am thinking of going with the 6" sewer pipe but the catalog I am looking at (Lowe's commercial business catalog) doesn't give a schedule # for the sewer pipe plus I can't find any 6" caps. I would think there would be that size of caps somehwere.
The largest caps I can find are 4". So I might have to go with that diameter of sewer pipe which again gives no schedule #. The caps will be cemented slip caps schedule 40.

You will have to forgive me because I don't really know that much about PVC pipe and fittings yet. By your questions you sound like you have a good knowledge of the subject.
I would be glad to hear your ideas and suggestions on a good way for me to go on this project. - pipe length / diameter / caps etc.... I am open to any ideas and suggestions.

Thanks for your interest in helping me out so far and will be glad to hear from you again,
Wayne

I am a mechanical Engineer, The stress in your PVS pipe can be computed given your desired tank pressure, Pipe Radii and Wall thickness...

Hoop stress, will burst your pipe, if it exceeds strength of plastic at 12,600 psi or use rating of pipe

hoop stress=PressurexRadius/wall thickness

For example, 6 sch40 pipe, at 30 psi

hoop stress=30x6.25/.280=669 psi stress is generated, you should be ok

Thanks for the help PropBoy,
That is something I would have never found on my own and definately had no idea how to figure for the psi. It's great to have such a large group of people out there to bounce questions off of. There is always someone out there with the right answers.

Thanks

Wayne

You may want to just grab a portable commerial air tank for about 20.00 or 30.00 bucks at Wal Mart, Lowes, etc. I don't know how much a length of PVC and two caps will cost but the commercial portable tank may be a option. Just hook you air pump to the inlet end of the tank.

Just a thought.

Shaun

Hi Shaun,
You are right. I went out yesterday and did a bunch of pricing on pvc stuff and small air tanks. Cost-wise it would be just as cheap and actually easier to buy an actual air tank because it all ready has the fittings. All I would need is probably adapters to connect up to the motor on one end and the airbrush on the other.
I'll tell my friend who gave me the pvc idea that it was a good idea and would have worked but I'm going to go the other route.
Thanks guys for all your input and help.
It is much appreciated,
Wayne
:-)

You can buy one for 70 dollars on ebay. .. whats the deal?

Wayne,
Follow this LINK. You will find, in Italian, a step by step guide on how mto build your own compressor from scrap parts. You can use the Google's languages tools to translate the page.
Hope this can help.
Ciao



P.S.: if you're not in a hurry I can translate it for you by mid next week... Just let me know

I do have a small diaphram compressor all ready which works good. But now that I am getting more into airbrushing I was wanting to upgrade myself to a larger, quiet, steady air stream type of compressor. Most of those have a pretty good cost to them. That is why I am looking into trying to possibly build a compressor.

Thanks for the link Fabio - I translated it fine with Google.
That is a nice compact design for an air compressor.

Thanks again everyone,
Wayne

I know this will sound really cheap, but bear with me.

I read an interesting article regarding this just a short time ago in FSM. Lots of ideas were offered (old fire extinguishers, dive tanks, etc.), but check this one out.

You can buy an air tank at Sears for about $14. (2 to 3 gallon size)
A regulator, filter, and fittings will cost you another $20 (maybe)
Air supply ? go to your local gas station and fill it when you need to.

I know, I know how cheap. I haven't tried it yet myself, but it's on my list of things to do.

I have in the past used a spare tire, as long as you have a good regulator it works.

Hi CRS,
I am open to any and all ideas. I like the idea of the small tank and definately the low cost.
Using a small 5 gallon air tank, does anyone know approximately how much airbrushing time it would give before needing refilling? I know it would depend on how much air you put into it in the first place. You say you have used a tire. How long does that usually last before you need to put more air in?

Thanks,
Wayne

Wayne,
sorry I can't give you a clock time on the tire usage. I could get two maybe three fighters or a good bomber project out of a tire. Remember I work in 1/72 scale so for larger scales that going to go down

Chuck