luke strawwalker
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Luke...I think I figured out what happened here...I had taken the day off to hang out with my son....throughout the course of the day I would shoot a coat of paint on the tubes, the nose cones etc....I had left the paint can out in the shed..I am wondering if the temp difference between the paint in the can, which had to be warm and the body tubes, which I had brought out from my air conditioned house is what caused the paint to crack...I have never had that happen before...I am going to let these dry and then sand them down and see how smooth I can get them...I am debating just cutting a section of paper and making a white body wrap for the bottom 3/4 of an inch on the core stage....
Yeah, big temp differences aren't really a good thing when it comes to painting... As a rule of thumb, it's always a good idea to : 1) have the paint can as warm as you can get it... (If it's cold, set it in a pan of very warm (not scalding hot) water for 20-30 minutes before painting to warm the paint liquid and propellant up in the can... this will raise the head pressure of the propellant in the can (finer atomization) and reduce the viscosity of the paint liquid itself (again, better atomization and flow-out on the surface), and 2) try to minimize the temperature difference between the surface your painting and the paint itself... If it's cold out, keep the can and parts in the house until you step into the cold shop area to paint... then bring it back inside to dry, if possible, or put it in a warmer environment (like an insulated box heated by a light bulb). In hot weather, taking stuff directly from the air conditioning out to paint isn't that good of an idea... better to set the parts out in the shop along with the paint for 30 minutes or so and allow everything to warm up well before shooting the paint, and leave the parts out there in the warm environment to dry.
You didn't mention what brand or type of paint you were using, or the humidity. Humidity can do some weird stuff. The other BIG problem nowdays is the paint formulation, which varies markedly from brand to brand. If in doubt, follow the can instructions on recoat timing EXPLICITLY. Some paints are EXTREMELY finicky and prone to doing nasty things halfway through the job (like Krylon) and some are virtually problem free (Wal Mart Colorplace). Others are somewhere in between, and the individual painter and his style or technique as well as his local environment DO play a big role in this as well... To me it sounds like you had an issue where a thicker top coat softened up the lower coats and caused it to crack or alligator.
If push comes to shove, you can wipe the tubes down with LACQUER thinner, which will alligator the remaining paint layers completely, and then just wipe the whole mess of the tubes with a paper towel and start over from scratch... lot easier than sanding everything down if the damage is widespread. If it's more "localized" in certain areas, then sanding it down and reshooting those spots is probably much easier and the way to go.
Good Luck! OL JR