Marc_G has an exellent thread on using Future/Simple Green to get a shine on a rocket in here somewhere.
I did find this, thank you. For those who read this, you can find it
here.
First one must define "polished'' as far as your end use. Are you talking about just a shiny mirror like finish or a aerodynamic finish. What are you trying to accomplish?
I'm looking for ways to polish the exterior of the rocket to maximize aerodynamic performance while adding a minimal amount of weight, if any.
For me it was the smoothest aerodynamic finish I could attain for an altitude related project. To do this I wanted all imperfections filled and a true and smooth, slick surface. I thought of it like this: don't add and fill as much as sand & remove.
This is exactly the approach I was looking for, thank you. I think that this is a pretty darn good mantra, to wit "don't add and fill as much as sand & remove".
There is no gloss coating I know of that can get you a smoother or better than this "polished finish" . It looks like crap but run your fingers over it, then any high gloss finish.
My current hypothesis is that the more finishing products - i.e. primer, paint, etc - added, the heavier the rocket, and the lower overall performance. So looks 0 and performance 10 is definitely where I'm currently headed.
You might look into a product called Micro Mesh. I use this stuff for fine woodworking projects and it's like magic.
Found it
here. Given the range of featured applications, this seems very applicable to my problem.
Now this is assuming a reasonably hard surface to begin with that CAN be polished. I doubt that paper airframe tubes would work. You would need to put some type of filler/finish on first - thinned epoxy would likely work.
I was actually thinking of preparing several sample body tube segments with differing structural strengthening methods, such as epoxy, thinned epoxy, epoxy mixed with carbon-fiber and/or cellulose-fiber, various combinations of CA, and finally wood glue. Then perform weighing and crush-testing on each to determine weight versus strength ratios for each methodology.
However, it remains to be seen if I have enough free time for this experiment.
It's definately an "elbow grease" type of effort, but after the first couple of grits, the polishing actually goes pretty quickly with each finer grit.
One problem I'm currently pondering is adding surface irregularities to the exterior of the rocket via repeated applications of, say, epoxy / sanding / flat-coat painting, etc. which would in turn affect aerodynamic performance.
Currently, I'm guessing one way to mitigate this factor would be by using a guide - such as a body tube section cut in half, longitudinally through the axis (resulting in a U-shape) - then glue the sanding medium to the section as a sanding guide.
Anyone every try something like this?
Then use automotive polishing compounds and buffing wheels. The best way to buff would be actual buffing wheels on a bench grinder, but most folks don't have the infrastructure. Next best is foam type wheels that you can use with a cordless drill. Most auto paint supply houses that sell the liquid compounds (I use Meguiar's) also sell the wheels.
I have done something similar using a hand drill on another project, however, I would be highly concerned about putting too much pressure on what, in the end, is a rolled paper tube.
Again, more effort than I've put into a rocket project, but I'd love to see your results.
good luck, s6
Thanks s6, I really appreciate the lengthy and insightful replies.