Various questions

QUOTE: Originally posted by tho9900 ---edit--- Tanky, remember that 12 psi is only an approximation on that regulator... it's an industrial one so you are guessing pressures in between marks... I'd try it out on an old model or some scrap plastic first and see, it might be adequate for ya... try thinning 2:1 ands see how it sprays, maybe go closer to 1:1 if it sputters on ya... save your money and later you can get an industrial compressor for $69 at Walmart... it'll go as high as you wanna pretty much, but for now I'll bet ya this one can still service ya...

Tanky? lol. i think i'll tsart calling my self that. Yours truly, Tanky. hehe.

QUOTE: Originally posted by dabicho less pressure, more thinning?

It all depends on the paint properties, but that is a good reference point.

QUOTE: less distance, less pressure?

Here again it would depend on what your goals are. Lower pressures up close lead to less overspray and spidering, yes.

QUOTE: less distance, more thinning?

Not necessarily. Once again it would depend on your intended purpose.
If you are trying for the finest lines possible, with the least amount of overspray, then all of these three points you asked would probably apply.

Mike

QUOTE: Originally posted by tho9900 ---edit--- forgot to answer Tankmeisters question.. 12 should be ok for ya Tank as long as you thin the paint properly... I sprayed with the blue ice and a regulator before and it does decent work. I think the main problem is the regulator causes resistance, and it has a bleed off I am sure, so the extra pressure you could use is just being bled off... play with it on some cardboard or something and see how you like it...

that's got me wondering, does anyone knows of a (rough/general) chart(s) of thinning ratio vs air pressure (vs distance(detail)?

Or what would be the general formula?
less pressure, more thinning?
less distance, less pressure?
less distance, more thinning?

you could try teflon TFE paste if the tape still allows leaks... it's what I started using recently. Resistant to 3000 psi at up to +400 deg Farenheit for gasses, lubricates and fills the threads completely...

seals unconditionally...

only a couple of bucks at the hardware store...

and it's harder to lose than the little roll of teflon tape I was on my 4th roll when I bought this stuff... they kept running away from home.. but be careful, it looks a lot like a tube of toothpaste.

---edit---

Tanky, remember that 12 psi is only an approximation on that regulator... it's an industrial one so you are guessing pressures in between marks... I'd try it out on an old model or some scrap plastic first and see, it might be adequate for ya... try thinning 2:1 ands see how it sprays, maybe go closer to 1:1 if it sputters on ya...

save your money and later you can get an industrial compressor for $69 at Walmart... it'll go as high as you wanna pretty much, but for now I'll bet ya this one can still service ya...

oh that could be my problem. i have it going around twice only.

Spray some soapy water on the connections and see where it bubbles.
Then you may need to put some more Teflon tape on the fittings to seal them better. Sometimed people only wrap the Teflon tape around the threads once or twice and that is not near enough. I would go around the threads 4 or 5 times to give the tape some thickness to bite into the threads and seal them better.

Mike

thanks for the responses guys. i get 12 without the trigger pushed down. i feel a little leak of air somewhere but dont know where exactly, and can't figure out ho ot fix it once i find it...

I noticed that pressure can also be affected by the addition of moisture traps, and even the length of the hose. When doing work like preshading, as in the example (Me262), I dialed the regulator down to 8 to 10 psi, so as to get as close to the model as possible to eliminate excessive overspray. Acrylics seem to respond better to lower pressure if you mix a little dish soap in the thinner. The best tip I took advantage of to acheive great results for low pressure fine line work, was to lube the needle, either with the storebought lube or just plain old vaseline. This made all the difference for me and my Badger 360.


Steve

QUOTE: Originally posted by Tankmaster7 2) When I put my regultaor on I seem to be getting a top pressure of 12 psi? why?

Is that reading while resting or with the airbrush trigger pressed down?
Compressors with no holding tank lose quite a bit more pressure while spraying than a compressor with a reserve of air in a tank.

QUOTE: 3) Is 12 psi an OK pressure for general coverage?

I would consider that minimal, especially for acrylics.
I use around 10 psi for the finest work and around 20 psi for general coverage.
You will find that lower pressures do not atomize paint quite as well for general coverage, but you can still get pretty good results I think.

Mike

I like gas physics myself... of course it's the only one I really got into and understood.. the rest interests me but as far as really understanding some or most of the rest...

My favorite physics problem in college was the "chicken and a half" one.... had most of us stumped for days..

---edit---

oops.... forgot to answer Tankmeisters question.. 12 should be ok for ya Tank as long as you thin the paint properly... I sprayed with the blue ice and a regulator before and it does decent work. I think the main problem is the regulator causes resistance, and it has a bleed off I am sure, so the extra pressure you could use is just being bled off... play with it on some cardboard or something and see how you like it...

Most of the time when I spray with my 155 it's somewhere about 15psi at the most and down to about 6 to 8 on the low side if doing detail.. so 12 should still get ya there..

well math sucks, but physics and metalworking (with speed record holder Shane Kenneally) and drafting are about what i like. physics is hard, but likeable.

QUOTE: homework... man i hate physics. stupid projectile motion and vectors

A person who builds model airplanes who hates projectile motion calculations? Physics and math were about the only things I enjoyed in school (of course when I was in school Sir Isaac Newton was still a peon and hadn't come up with his laws yet)

homework... man i hate physics. stupid projectile motion and vectors

QUOTE: 1) What pressure does hte blue ice deliver unregulated?

No clue ... I assume 1337 is right, he usually does his homework.

QUOTE: 2) When I put my regultaor on I seem to be getting a top pressure of 12 psi? why? (the threads have teflon all ovber them too!)

The regulator causes a certain amount of resistance on the air flow which may cause a slight drop in outlet pressure. When you don't have much to work with to start with (i.e. 10-20 psi) losing a couple is noticeable.

QUOTE: 3) Is 12 psi an OK pressure for general coverage?

Should be. I do the bulk of my spraying around 15 psi. You would probably see better atomization around 18-20 psi, but if it works then it works.

QUOTE: 4)Or would the unregulated pressure be bettr for that? (if so i'd only put the regualtor on when i need fine lines)

Personally I wouldn't fool around with taking it on and off. Just try it and see if it works. If paint comes out the airbrush and covers the model the way you want it to, then everything is fine. If you aren't getting the finish that you want or the coverage that you want, then it's time to see if there is a way to make things better.

QUOTE: Originally posted by Tankmaster7 1) What pressure does hte blue ice deliver unregulated? 2) When I put my regultaor on I seem to be getting a top pressure of 12 psi? why? (the threads have teflon all ovber them too!) 3) Is 12 psi an OK pressure for general coverage? 4)Or would the unregulated pressure be bettr for that? (if so i'd only put the regualtor on when i need fine lines) Thanks, Tank.

1. around 10-20
2. maybe the comp can't do any more
3. yes