Read through this thread and want to comment on the polishing of the clear resin.
Just a bit of history: I was a gunsmith for several years and later converted my shop and skills to jewelry making and metalsmithing.
That said. I have successfully polished a flat support piece off of one of our models just as an experiment. First, make sure the part is well cured. Second, wet sand the part with successively finer abrasive paper to a 600 finish.
Note: As with any sanding and/or polishing operation, one always sands or polishes in a different direction from the prior grit. So if your 400 grit sanding was from right to left, your 600 grit sanding would be from top to bottom. This helps you avoid ripples and also lets you see when you have removed the sanding scratches from the previous grit.
At this point I used ZAM polish on a 10" loose muslin polishing wheel, running at 1800 RPM. The wheel must be kept clean by occasionally using a buff rake and as stated in Nigels post, the part must not be allowed to get hot by heat generated by friction of the wheel. To avoid that you need to use light pressure when presenting the piece to the wheel and keep your wheel clean and well charged with polish.
Not everyone would have or want a polishing motor that can spin a 10" wheel but all other conditions/cautions would apply.
One general note, machine polishing relies on SFM, (surface feet per minute) thus the 10" wheel @ 1800 RPM. So, if you are using a smaller wheel, it will need to run faster to accomplish the same level of finish as a larger wheel running slower. The only problem with small wheels running fast (as with Dremel) is that you have a greater chance of over heating the plastic, thus melting it and getting deep “drag” marks on the piece you are trying to polish.
Hope this info helps.