DECANTING QUESTION - BIG 3 LACQUER-MAKERS

[fseva]

This quetion applies to decanting lacquer spray cans by Tamiya, Testors & Model Master - I usually decant at least 2oz from a can (in regard to Tamiya, that's about all I ever get).

I need to know a good rule-of-thumb for determining when the compressed gases in decanted paint or no longer present - I have had one too many accidents with volcanic eruptions of paint that I had assumed had gassed-out long enough!

How long would you recommend allowing the paint to gas-out? Is there anything that will help it along - stirring with a battery-operated stirring wand, etc., that will help release the bubbles of gas?

Edited April 3, 2015 by fseva

[pharoah]

You might let the room gas-out if you do this indoors.

Here's the way I do it. First I only decant what I'm going to need. I use dixie cups held in my had with a paper towel between the cup and my hand. I spray a little over what I need,put in a few drops of thinner,and dump it in the airbrush.

Another thing - Why would you decant Tamiya spray paints unless you're mixing a special color? I have gotten great results straight from the can. Testor's...that's another story. Good luck!

[High octane]

I've got good results with just spraying Tamiya, Model Master, MCW, Dupli-Color, and Black Gold right from the can. Just "shake and squirt." No mixing, no water traps, no adjusting pressure or spray pattern, no noisy compressor, and NO clean up.

[10thumbs]

Hi Frank, after a day or so, unscrew the top of the container you keep the paint in, can you hear the gas come out? Then re-close and shake the bottle, does it still pop open? If not, I'd say it's ready.

[64SS350]

I read on here once a guy turned the can upside down to release all pressured gas and then drilled a hole in the bottom to pour out the paint.

Now I don't know if the paint would still have gasses in it or not since it wasn't decanted, or but from simply being in the can together.??

[Guest]

I decant them directly onto the model.

[fseva]

Hi Frank, after a day or so, unscrew the top of the container you keep the paint in, can you hear the gas come out? Then re-close and shake the bottle, does it still pop open? If not, I'd say it's ready.

Wow - that long? I guess I deserve a volcano of color...

[fseva]

I decant them directly onto the model.

Messy... very messy...

[fseva]

I read on here once a guy turned the can upside down to release all pressured gas and then drilled a hole in the bottom to pour out the paint.

Now I don't know if the paint would still have gasses in it or not since it wasn't decanted, or but from simply being in the can together.??

Yes, I've read of that - always figured it was a darn dangerous thing to do...

[curt raitz]

Decanting is fairly easy,

I hold a flexible straw to the nozzle and spray into a small glass bottle (Badger).

I leave the bottle un-covered for at least 24 hours...

"gassing" out paint that has been decanted does take a long time.

[fseva]

You might let the room gas-out if you do this indoors.

Here's the way I do it. First I only decant what I'm going to need. I use dixie cups held in my had with a paper towel between the cup and my hand. I spray a little over what I need,put in a few drops of thinner,and dump it in the airbrush.

Another thing - Why would you decant Tamiya spray paints unless you're mixing a special color? I have gotten great results straight from the can. Testor's...that's another story. Good luck!

I always thought that I had better control airbrushing, and I have just recently started trying a few Tamiya colors. So, I'll give them a try next time - straight out of the can - perhaps in the long run, I won't waste as much paint (I only got about 1 3/4oz out of the last can of Tamiya I decanted).

[935k3]

These work well, cone cups for water coolers. Cut off bottom tip, sit in jar and spray until desired level is reached.

[Jeff Johnston]

Decanting is fairly easy,

I hold a flexible straw to the nozzle and spray into a small glass bottle (Badger).

I leave the bottle un-covered for at least 24 hours...

"gassing" out paint that has been decanted does take a long time.

This is exactly how I do it too. I actually use masking tape to secure the straw so I don't bet paint all over my fingers. Well. more paint..I usually have paint on my fingers haha

I also agree it takes 24 hours with Tamiya. The one exception is Testors wet look clear. It gases out fairly quickly. Everything else I just set the cap loosely on the badger jar and let it sit for a day. When you check it, just screw the cap on and give it a shake. If when you loosen the cap you hear a pssst (like you are opening a soda can) its not time yet.

[fseva]

This is exactly how I do it too. I actually use masking tape to secure the straw so I don't bet paint all over my fingers. Well. more paint..I usually have paint on my fingers haha

I also agree it takes 24 hours with Tamiya. The one exception is Testors wet look clear. It gases out fairly quickly. Everything else I just set the cap loosely on the badger jar and let it sit for a day. When you check it, just screw the cap on and give it a shake. If when you loosen the cap you hear a pssst (like you are opening a soda can) its not time yet.

I have actually used some of the newly-decanted paint, and it was still bubbling in the gravity cup, but it went on just fine. I am really surprised that it takes at least 24 hours to be assured that all the gases have been released, especially in the case of such a small quantity! I usually decant to a larger jar and then have to transfer the paint to smaller bottles (losing some paint in the process), but I always felt that the larger surface area would allow an easier release of compression gases... guess that was wrong, too!

[Danger]

When I decant I usually put a toothpick in the jar to speed up the de-gassing process. Be careful putting it in as the toothpick causes a rapid bubbling effect that may overflow if you're not careful.

I also set the cap on top upside down. This covers the open jar so nothing can fall in. The foam gasket that is inside the cap has melted into the paint as it's de-gassing.

Danger

[fseva]

When I decant I usually put a toothpick in the jar to speed up the de-gassing process. Be careful putting it in as the toothpick causes a rapid bubbling effect that may overflow if you're not careful.

I just decanted a full can of Lime Ice lacquer (Testors), and I just decided to leave the straw inside the jar, to see what it would do... I actually stirred the paint with it, and it bubbled furiously for a little while and I left it alone. I think it was an hour later I tried again, and hardly anything was going on. I got so interested in why this was happening that I decided to transfer the paint to a much larger jar so that I could give it a good shake. A couple times, I heard gas escape when I took the cover off, but nothing major. I gave it another hour and transferred the paint into 2oz bottles - about 1.5oz in one and 1oz in the other, which left enough room for me to test again by shaking - just a little at a time - and nothing! I was so surprised - the whole thing took less than 3 hours!

Edited April 13, 2015 by fseva

[Art Anderson]

I've been decanting rattle can paints for use in an airbrush since the middle 1960's, and settled, years ago on simply spraying the paint directly into the color jar of my airbrush! Now, at first, I did get paint all over the fingers holding that jar, but over time I've learned to carefully modulate the spray so that the paint being decanted doesn't just blow right back out of the bottle.

It took some practice to get that, to be honest, but that's how I still do it, 50 years later, and I seldom get more than just a bit of overspray on the fingers holding the color jar. The secret? I learned to spray the rattle can stuff against the side of the bottle, NOT directly to the bottom of it.

As for "out gassing", I never worry about that--after all, if one sprays rattle can paint directly from the can to the model, it's not outgassed before it hits the body shell, now is it?. Of course not. In addition, where 40 years ago, paint manufacturers were using FREON as the propellant, which took a lot longer to bubble out of the paint--nowadays, since the International ban on the use of Fluorinated Hydrocarbons (which is what FREON was), most all aerosol cans, from paint to shaving cream, use propane or butane gas as the propellant, and that evaporates very, very quickly out of the liquid paint once it's out of the spray can.

That's my technique, and I'll stand on it.

Art

Art

[DeeCee]

I agree 100% with Art, been doing exactly the same thing for over 20 years, and NEVER had a problem once i learnt to spray it into the side of the jar,

and usually only ever decant what i need for the job i am doing, it keeps for ever in its original can.

As for gassing out, it can do all the gassing it likes while i set up the airbrush, which usually takes about 1 minute. ( i only ever use auto acrylics, so got no clue about testors etc ).

Edited April 10, 2015 by DeeCee

[Mike_G]

I've also shot freshly-decanted Tamiya lacquer in my airbrush with no problems.

[fseva]

As for "out gassing", I never worry about that--after all, if one sprays rattle can paint directly from the can to the model, it's not outgassed before it hits the body shell, now is it?. Of course not.

Hmmm... had to think about this one awhile... If the gases are there to propel the paint out of the bottom of the can, then you would think the gases would all be expelled during the spraying process!?

[Ace-Garageguy]

Hmmm... had to think about this one awhile... If the gases are there to propel the paint out of the bottom of the can, then you would think the gases would all be expelled during the spraying process!?

Most likely. The sudden release of pressure when the paint with dissolved gas in it escapes through the nozzle pretty well triggers the release of all the dissolved gas.

Just like the Coke you lick off the floor (after it sprays all over everything when you drop the can) is flat.

Spraying the stuff against the wall of a container does the same thing.

Really.

[935k3]

I also spray right into the jar first but after it is too full I switch to the paper cone funnel. The worst stuff for gassing problems is all of Tamiya's clears(TS13,TS79 and TS80). You can spray without gassing out but it is intermittent. When spraying flats not properly gassed out it cause a wet drop on what your painting which is not as flat as the surrounding area. I do sometimes spray small amounts of paint right int the bowls(cups) on my gravity feed airbrushes.

[Ace-Garageguy]

I've had some Testors enamels bubble mysteriously on occasion if sprayed from the can on to a part. The paint hits, flows out beautifully slick, and then will bubble a bit, but only on a sharp edge.

Not contamination, or too-wet spraying of the material, cause I kinda know how to prep and spray. Very odd. The wheels on my heavily re-worked '32 Ford gluebomb are Testors dark red enamel, and 3 of 4 wheels (painted at different times) bubbled only on the outer rims. After assuming contamination and stripping them and re-prepping/re-painting several times, the only way I could get rid of the bubbles was to let the paint cure completely for weeks, and sand / polish the rims...VERY carefully.

Hammering the paint on would have resulted in bubbles where the paint was thickest, and pooled...not where it was thin on the sharp edges.

At this point, I can only assume this was some odd dissolved-propellant gassing phenomenon...but it still doesn't make much sense.

[935k3]

When paint is not gassed out it will bubble out at the tip of the airbrush without even depressing the trigger. The paint starts to collect on the tip then when you start spraying a wet drop, not atomized sprays onto what you are painting. Look at your tip an you will see it happen.

Edited April 13, 2015 by 935k3

[Art Anderson]

When paint is not gassed out it will bubble out at the tip of the airbrush without even depressing the trigger. The paint starts to collect on the tip then when you start spraying a wet drop, not atomized sprays onto what you are painting. Look at your tip an you will see it happen.

In my almost 50 years of decanting spray cans into airbrushes, I've never experienced what you mention, UNLESS the vent hole in the color jar is clogged.

Art