On the Use of “Chrome” Spray Paints for High Power Model Rocketry
Every store that offers any form of typical spray paint in a can, seems to offer “Chrome” as one of their choices. The can always delivers a cap with what appears to be a section of bumper from a ’57 Chevy, somehow repurposed into a spray paint can lid.
We here at One Way Rocketry implore you to just say “No!” to this sham. There is no chance that a single-part hardware store spray can will be able to deliver a truly polished, metallic finish. In fact, normal hand tools are almost always a chromium-alloy tool, and usually silver colored and not “chrome”. An extra step has to be taken to either polish the metal, or dip the tool into a higher concentration of chromium to get the mirror finish. I don’t think this spray can is going to deliver on any of that. And there is certainly no chromium in this spray paint can.
“Spray Chrome”
There is, however, a system usually referred to as “Spray Chrome” that will coat your part with a base primer, and then a very thin layer of actual silver, which will impart a mirror finish, and is actually how mirrors are made. This requires specialty paint spray guns and air compressors at a minimum, along with paint spraying skills, access to a spray booth, and usually a kit starting around $500 and of course up from there.
“Spray Chrome” seems like a highly lucrative business idea with potential customers in auto repair and customization, and in modelling of any kind, including High Power Model Rocketry. I might pay $20-30 for my HPR1 3″ ogive nosecone to have a perfectly polished finish, but not much more than that, and it really better be like a funhouse mirror.
But even then, this is Spray Silver, not Spray Chrome, and the color of a polished silver surface will technically not match the color of polished chromium. At One Way Rocketry, we hope to test some of the leading Spray Chromes in the near future, meanwhile the top three Spray Chrome manufacturers we intend to investigate are:
I should think small jobs like a rocket nosecone would be perfect for a Spray Chrome business, but the perfect chrome finish certainly will not happen with a spray paint can grabbed from the drugstore.
Actual Real Chrome
Yes, your model rocket nosecone can have a truly metal, polished chrome finish. The essential process is basically the same for any chromed plastic part. A conductive base primer with real metal particles is applied to the nosecone, which will allow an electric current to pass through the entire surface of the nosecone. This conductive nosecone is connected to NEGATIVE and then dunked into a tank of real chromium which has a POSITIVE charge applied. The chromium molecules in the tank are then attracted and attach to the molecules on the surface of the nosecone.
The flaws are that the metal is very thin and brittle, and the plastic is quite flexible, and the chrome finish could blister or crack if the underlying plastic base goes through any temporary movement, which is the purpose of plastic. A hard landing might crack your chrome. A hard landing could also crack any of your finishes, including the original nosecone itself, so the risk is omnipresent, and probably worth it. Especially if you plan to launch your High Power Rocket only once for certification and then retire her.
The positives are that this process, once set up, is quite straightforward and simple, and gives very good, very reliable results. Further, the real metal finish is much more durable, and way less likely to scratch than a thin layer of silver. Also, this process will apply much more metal than is applied with the “Spray Chrome” method.
The negatives are the health and environmental impact of all the chemicals involved, especially chromium, and the responsibility of handling them properly. We believe it would be a great business to start, and would be able to chrome parts for many different areas of interest, which would keep the work fresh.
Alternative Spray Paint Options
Testors makes various truly metallic colors made for spraying models. There are many which attempt to emulate the real color of actual metals, like aluminium which is a bit whiter than chromium and magnesium. Model airplanes and jets make use of these specific colors. If you can be happy with a real aluminum or magnesium color, these sprays will give you an amazing finish. The cans are smaller, since they figure you are using them for a 1:25 scale fighter jet, but it works out that one small can will actually put a few good coats on a medium sized, HPR1 model rocket nosecone. Just don’t expect to do the entire rocket with one can.
We find the model spray paints work much much better than hardware store spray paints, and much better than auto spray touch up paints, which take forever to dry and go on entirely too thick for small models. The way it sprays seems superior, the very fine particles coat the model better. They never seem to clog, unless your finger is in the way. The results are more consistent with Testors modeling enamel versus hardware store spray paint.
Winning “Spray Paint Chrome Effect”
The most pragmatic “chrome” spray option we have found for the regular High Power Rocketry builder is to use Testors CreateFX Silver Glitter paint.
Not only will the result actually look like the lid of the can, there is enough texture involved with plastering the surface with billions of glitters that it hides loads of imperfections. It does require its matching glitter sealer, and you will want to use a gray colored primer. We do find one can of this will do one medium sized HPR nosecone with two or three coats. It is wise to have a spare can; we promise you will think of something to do with it.
