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SatelliteInterceptor
02-10-2008, 03:56 AM
For the past 5 years, I've been painting all of my rockets with Rustoleum spray paints. At times, I will accidentally get some spray paint on the bottom engine mount ring, the bottom of the engine tube, the inside lower section of the body tube, as well as the metal engine hook. I haven't checked, but I'm almost certain that all spray paints are flammable, yet I've never had a problem with flames from the thrust of the rocket engine, igniting the dried spray paint. I was wondering if anyone has ever had any problems like this ?

Also, in the near furure I am going to purchase a few cans of Rustoleum clearcoat spray. I plan on coating all of my rockets with the stuff. If I accidentally spray some clearcoat on the 4 above mentioned areas, will I have a problem with engine thrust igniting the dried clearcoat ? Clearcoat is flammable. I'm 99.9% sure that it is. I need some advice on this before I go ahead and do this to my rockets. Thank you in advance. :-)

Rocket Doctor
02-10-2008, 06:21 AM
For the past 5 years, I've been painting all of my rockets with Rustoleum spray paints. At times, I will accidentally get some spray paint on the bottom engine mount ring, the bottom of the engine tube, the inside lower section of the body tube, as well as the metal engine hook. I haven't checked, but I'm almost certain that all spray paints are flammable, yet I've never had a problem with flames from the thrust of the rocket engine, igniting the dried spray paint. I was wondering if anyone has ever had any problems like this ?

Also, in the near furure I am going to purchase a few cans of Rustoleum clearcoat spray. I plan on coating all of my rockets with the stuff. If I accidentally spray some clearcoat on the 4 above mentioned areas, will I have a problem with engine thrust igniting the dried clearcoat ? Clearcoat is flammable. I'm 99.9% sure that it is. I need some advice on this before I go ahead and do this to my rockets. Thank you in advance. :-)

In my experience, once the paint is dry, I haven't had any "fires" in the tail section. To prevent paint from going inside the motor tube during painting, you could use a cork or spent engine and mask the engine hook with blue painters tape. I've also used clearcost after painting with no problems.

FYI Just make sure the clear coat is compatable with the decals.

tbzep
02-10-2008, 09:52 AM
Yes, it's the solvent that makes it flammable, not the pigment itself.

ga1ba2
02-10-2008, 05:39 PM
The whole rocket is flamable. Paper and balsa burns rather easily. If anything , the dried paint might protect the rocket somewhat but won't make it any more flamable.

Mark II
02-10-2008, 08:52 PM
Yes, it's the solvent that makes it flammable, not the pigment itself.
Also the propellant in the spray can. Since the ban on CFCs, many aerosol cans use propane as a propellant. But, of course, that disperses as soon as the spray leaves the nozzle. And the paint solvent evaporates as the paint dries, so the painted surface, once dry, has no unusual flammability that is imparted by the paint itself. I often paint the aft ends of my rockets around the motor tube, as well as the exposed outer surface of the motor tube (and often, inadvertantly, the motor hook) and I have never had any problems with any of these surfaces igniting and burning from the motor exhaust. Scorching, yes, especially on the motor hook, but no burning. :o ;) You can use high-temp paint (like the kind used to paint barbecue grills or the kind used to paint car and truck engines, for example) on these surfaces to make them more resistant to scorching, and to make those surfaces more durable and weather-proof in general.

Mark

Mark II
02-10-2008, 09:05 PM
I forgot to add: clearcoat is just paint without any pigment. So it will handle heat just as well as any other paint.

Now back to the Grammys. ;)

Mark