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Tau Zero
09-21-2006, 10:01 PM
In the latest issue (#167) of Apogee Components "Peak of Flight" newsletter:

http://www.apogeerockets.com/education/newsletter_archive.asp


...Tim Van Milligan, et al, mention the "Scotch tape on your forehead" method of masking fins, etc. It appears to me that you'd probably want a "low stickiness" brand of Scotch tape, as well as waiting until the undercoat had dried before applying the tape.

Generally speaking, how long should I let a coat of paint dry *before* I try this "new" :rolleyes: procedure? Usually I wait 24 hours before putting the next coat on. (I'm fighting the spray-painting equivalent of "Launch Fever," apparently. :eek: )


"--Anyone? Anyone? ...Bueller? Bueller?" ;) :D


Thanks in advance,

sandman
09-21-2006, 10:24 PM
Here is a tip I gave a long time ago and so many guys have used it that it is almost like a model rocket finishing "Comandment".

If you can still smell the paint, thou shalt not repaint!

If you can smell it, it's not ready!

Go watch TV..anything...leave it alone!

Paint cure isn't always a direct relationship with time.

Temperature and humidity are a very big influence on cure time.

Tau Zero
09-21-2006, 11:05 PM
If you can still smell the paint, thou shalt not repaint!

If you can smell it, it's not ready!

Go watch TV..anything...leave it alone!Excellent counsel, Sandman. I'm going to bed early. ;) :D :)


Cheers,

Doug Sams
09-22-2006, 12:47 PM
Generally speaking, how long should I let a coat of paint dry *before* I try this "new" :rolleyes: procedure? Usually I wait 24 hours before putting the next coat on. (I'm fighting the spray-painting equivalent of "Launch Fever," apparently. :eek: )


"--Anyone? Anyone? ...Bueller? Bueller?" ;) :D Jay, I just go by the paint can recommendations, which are, IIRC, 1 week for RustOleum, and on the order of 24-48 hours for the other hot-solvent enamels such as Testors and Krylon.

There's also a near window, wherein if it's only been a few minutes/hours, you can apply more paint, but the underlying coat may not be cured well enough for taping or sanding. But you could apply a blend color this way.

One way around all this is with acrylics, but I don't have firsthand experience. Bryan Nelson, a DARS regular, is also a body shop manager. He wanted to return a favor for another club member, so he applied a gorgeous mulit-color, patterned paint job using acrylics, and did it all in one extended paint session. The mulitple colors would take me weeks to do with RustOleum, but were all done in a day by Bryan.

He was able to put down the base coat, then mask and shoot multiple top coats right away. Basically, in the time it takes to prep the airgun/brush for the next coat, the previous one is dry enough to mask.

So I'd say to investigate acrylics and see what you can learn. BTW, notice I didn't specify the solvent. I know hobby stores carry a brand of water-based acrylics (I can think of the brand) but I believe there are also oil-based ones, too.

HTH,
Doug

CPMcGraw
09-22-2006, 01:32 PM
...I know hobby stores carry a brand of water-based acrylics (I can think of the brand) but I believe there are also oil-based ones, too.

HTH,
Doug

Liquitex (in tubes) is the one I've had good experience with. You add an airbrush medium with it along with just a little water to make it sprayable. The final result is a chalk-flat finish, which is OK since you're going to apply a gloss coat over it all...

ghrocketman
09-22-2006, 02:13 PM
On ALL of my rockets I use good "old fashioned" organic solvent based paint.
None of that water based supposedly "environmentally friendly" guff for me !
In fact I usually use new-old-stock vintage "high organic solvent content" Aero Gloss color dopes applied with an airbrush, unless the model has plastic parts. If plastic is involved I switch to enamel (Testor's, Krylon, Rust Oleum, etc) for the entire build to avoid incompatibility issues.
I rarely build models with plastic content, thus it's usually Aero Gloss & the airbrush.
I have cases of pint and half-pint cans of virtually all the vintage colors of Aero Gloss, including Royal Purple and Bendix Red.
I gave various acrylic paints a try and hated them. I don't like to HAVE to apply clear if it is not needed....it only adds more weight. Aero Gloss has a beautiful shine without any of the need for clear if applied correctly.

Green Dragon
09-22-2006, 08:26 PM
regarding acrylics - not sure about spraying the artist tube ( oil base ? ) acrylics, but I;ve had good results airbrushing water based craft acrylics.

would have to check the 'stash' at the shop for the various brands, but they;re the round bottles sold at Michaels,etc for tole painting and general craft use.

some real good colors, too - I'll get a pic of my non-stock-paint Delta Clipper in metallic turquois, if I can get good lighting ( maybe tommorrow in the sun ).

Generally I still use 95% spray-bomb enamels, usually off-brand ( dolalr general, or close-outs), of, if I pay the bucks, prefer Plasticote over Krylon, but that's just me .

~ AL

SEL
09-22-2006, 10:27 PM
I've been using Scotch tape for masking ever since I read Peter Always first "Art of Model Rocketry" book back in 89/90. I first smooth the tapeout on to a metal ruler to take some of the "stick" out of it.
Much cleaner edges than I've been able to get with masking or painters tape.

Sean

In the latest issue (#167) of Apogee Components "Peak of Flight" newsletter:

http://www.apogeerockets.com/education/newsletter_archive.asp


...Tim Van Milligan, et al, mention the "Scotch tape on your forehead" method of masking fins, etc. It appears to me that you'd probably want a "low stickiness" brand of Scotch tape, as well as waiting until the undercoat had dried before applying the tape.

Generally speaking, how long should I let a coat of paint dry *before* I try this "new" :rolleyes: procedure? Usually I wait 24 hours before putting the next coat on. (I'm fighting the spray-painting equivalent of "Launch Fever," apparently. :eek: )


"--Anyone? Anyone? ...Bueller? Bueller?" ;) :D


Thanks in advance,