Rustoleum- The best of times/ the worst of times

[bernomatic]

When they work, Rustoleum rattle can paint can give a really nice finish. When they don't, well let's just say I don't buy the paint for rockets anymore.

Now the primers, I am still using the primers but had my first nozzle issue with a primer last week. We'll have to see how it goes.

[Rocket Babe]

I have never used anything except Krylon, even after they messed up the original formula. When I was a kid there was a model spray paint I think was called Pla??? It was ok for plastic model cars and planes.

I tried Rustoleum once right after Krylon changed but NEVER again.

[luke strawwalker]

I use the Rustoleum "wet sandable" primer for everything-- does a nice job and leaves a really nice primer layer... "damp sand" it and it will look like a silky matte finish, so all you need to do is shoot a nice color coat or two and *not screw up* and it'll come out looking great.

I like the Walmart Colorplace stuff for basic black and white... they have only the most basic "primary colors" but for black and white (like scale NASA-type models) it works great.

I've picked up a few airbrushes and a trim gun from Harbor Freight... for large rockets or HD finishes, that's probably the ticket. I bought an external mix airbrush from TSC a few years back for about $20 bucks IIRC with some extra paint jars. Can't do "detail work" with it, but for covering large surface area (like base coats) without having a ton of clean-up and stuff, it should do nicely.

Later! OL J R

[Ez2cDave]

Who remembers "Varathane", back in the 1970's ?

[luke strawwalker]

Who remembers "Varathane", back in the 1970's ?

I remember seeing that stuff but it was before my time. Grandpa and Dad used it at some point. Was it good??

Later! OL J R

[luke strawwalker]

When it comes to spray cans, there's two things to remember... 1) you can NEVER shake the stupid thing TOO MUCH, and 2) warming it up first helps IMMENSELY.

The solids tend to come out of the suspension in the can (settle to the bottom) and that dinky BB in there can only do SO much to stir it back up again... I'm seriously considering building a "can shaker" out of an old drill and a spring some sort of way, with an offset weight or something and a way to clamp the can to the drill to shake the stupid things up. Basically you could leave the thing to shake for an hour and be that much better off LOL:) What really kills cans is when a little "booger" of thick goopy paint solids that are *partially* dissolved ends up floating around in the can or breaking loose from the bottom or something and ends up pulled into the straw and up into the valve. When it gets there it generally gums up the works and plugs it up to the point the valve no longer works. Sometimes you get lucky and the gob ends up in the tip, which is easier to deal with. Sometimes it plugs up the straw like a lemon seed in a glass of tea and then you're kinda SOL... I've heard of guys blowing high pressure air back down through the valve and straw to dislodge crap and 'revive' the can... but that's a lot of trouble and you need a good 130-150 PSI compressor to do it...

The other thing is, the propellants get weaker with time and use... there's only SO much propellant in the can, and when it's gone, it's gone. I've had WD-40 cans run out of propellant before they run out fluid... usually when they rode in the tractor toolbox, which seemed harder on them for some reason. I'd usually discover this fact in the field when I came up against a rusty and stuck bolt and NEEDED the friggin' stuff to get going again. SO I'd usually just punch a hole in the can with a screwdriver and resort to the "dribble method", but of course that doesn't work so well with spray paint. Of course the propellant works by being a low cryogenic fluid that boils off at "room temperature" to create head pressure in the can, at which point that sufficient pressure is created it raises the boiling point of the fluid to above the ambient temperature, and it quits boiling, and the pressure stabilizes. The warmer the can and contents, the higher the vapor pressure of the propellant, and the more boils off and raises the pressure in the can to force the contents out. SO warming the cans up by setting them in warm water (hot as you can stand to put your hands in) for a few minutes before use (to give time for heat transfer from the water, through the steel can, and into the contents, so it all reaches thermal equilibrium) will help to get the pressure up in the can and keep it up. Remember as the can is used and the propellant boils, it creates a "refrigeration" effect and actually cools the contents of the can down-- so starting with the contents as hot as possible will provide a lot of "latent heat of evaporation" to help overcome the refrigeration effect as the propellant boils off in the can due to phase change. Water provides the quickest transfer of heat into the can, since water is 860 times denser than air. Plus, hot water from your tap is probably set for about 115-125 degrees and that's plenty to warm up a can of paint. Give it at least 10-15 minutes for the heat to penetrate the can and the liquid in the can to warm up. 20 minutes or so might even be better.

I bought a few airbrushes from various places, including an external mix from TSC, and an internal mix from *somewhere*. I also have a "trim gun" I bought at Harbor Freight, and so I can just get regular paint from the store or auto supply and use that if I have to. They were cheap enough so I bought them, figured I'll probably need them someday. I've found that by shaking the ever loving CRAP out of the cans and warming them up THOROUGHLY before use, I can avoid about 98% of the problems with clogging or low pressure coarse "orange peel" spray...

Later! OL J R

PS. BTW, leave that stupid "paint and primer in one" crap in the store... fine for painting lawn furniture, but for rockets, if you want a good finish, you NEED to spray on a good coat of primer, sand it down a couple times with 220 grit and then 400 grit wet/dry paper that's been dipped in water, and you can get the primer smooth as silk. Then all you have to do is shoot on a couple good even light color coats to get smooth even coverage, and you'll have a practical mirror-reflecting surface. 99% of paint job quality is in the PREP WORK sanding the surface after it's primered...