Instructables

Best to polish clear cast resin?

my mum's in the process of making a lot of clear cast jewellery and is having trouble sanding imperfections down and then getting them back up to a good shine, as they're transparent it does need to be a good clear finish...

Like Steve & Burf said, with a couple of adds:
1) If you don't have a powered buffing wheel, there's a drill attachment you can get at Home Depot/Lowe's/etc. that holds small diameter buffing wheels. It's not very expensive at all, and works very well.
2) They also sell a variety of polishing compounds there. Check the back of the package for the right combination to use on plastic/resin.
3) You can also use a felt wheel in a Dremel for jewelry-sized pieces, but not as effectively for larger pieces.
I also make resin jewelry and have found that the best way for me is using a dremel and wet/dry sandpaper. I use a one inch hole punch and make my own sanding discs from 400 grit to 3000 grit and then use turtle wax or treewax (carnuba) wax on a buffing wheel. You end up with a nice high polish
nicelly2 years ago
A fantastic advantage for men and those that dread activities with all the disastrously stylish (the kind of clerk that works at the perfume countertop) could be the on-line perfume keep. The particular problem is that you simply can not scent before you buy. In a lot of shops right now, you simply can’t attempt scent about quite definitely, sometimes. For the most part malls you need to ask designed for a sample of an aroma and they offer this for your requirements on the tiny matchstick involving document which they wave all around in mid-air as it would turn into a dove along with fly aside.
http://www.italianralphlaurenpolo.com/polo-ralph-lauren-uomo-c-1.html
vm112383 years ago
honestly I myself have been thu this with resin jewelery and I found that instead of going thru all that work especially if you are mass producing a whole lot ( whichbecomes time consuming ),that it is better to prop your piece so that it is raisedup off your flat surface and they do have a tray for this as well at Resin Obsession (google it) . what i do id wrap packng tape around the area for extra protection , prop it up off the work surface , then mix up a small batch of resin. use something like a popsicle stick to drizzle resin towards the center of the piece to be coated and let it level itself out to the edges. let it dry/cure and the shine is great. you can also use a paintbrush and paint on the resinespecially f you have a piece that cured with a "dimple in it or that got scratched.
RTV Steve4 years ago
Some resins are polishable and some are not. There is some good advice above but if you use the right resin from the start it will make life easier. Are you using urethane or epoxy? Sometime some of its own resin thinned used over the original can produce results. www.RTVMoldMaking.com has clear casting resin that can be polished. This and easy to use too.
nepheron4 years ago
 Use mildly abrasive car wax.
holeshot4 years ago
One of my hobbies is building plastic models, and eliminating scratches in clear parts is common chore. 

If you use sandpaper, you'll need to go to VERY fine grades--like 10,000 or 12,000 grit. 

In addition to the Novus plastic polish previously mentioned, you can also try toothpaste, that is a very fine mildly abrasive polish.  You can often find Novus in auto parts stores too, since it's also used for getting scratches out of convertible top windows. 

Finally--and you can even try jumping right to this step--try dipping them in Johnson's Future floor polish.  (It's also called Pledge with Future Shine or Johnson's Kleer in some parts of the world.)  A great tutorial is here: www.swannysmodels.com/TheCompleteFuture.html

Good luck!
Curtis

fbarcus4 years ago
I don’t know much about jewelry but I used to make custom windows for aircraft. When we had to polish them to a clear finish we used a liquid plastic polish and a cloth. I would suggest you use something like Novus 1 or Novus 2 from tapplastics.com . A good microfiber cloth can be used to rub it onto the plastic. If the pieces are small and it’s not practical to polish them by hand, maybe you can buy a rock tumbler from your local hobby store and line the inside of the drum with soft felt. That way you can load a number of pieces into the drum with the polishing compound and run it till the plastic is polished.
 
I’m just thinking out loud. If it works, please post an instructable about it.
Kryptonite4 years ago
Cover the rough area in a thin layer of strong, transparent glue?
chriskarr4 years ago
As RMS (I lol'd) said,

A Dremel buffing attachment would, very likely, be the best option for low-cost, though I have noticed that they do not tend to last long. A polishing compound, in my experience, does not do well with plastics.

If there must be absolutely zero mistakes and as close to zero material taken off as possible, I recommend not using a polishing compound, sanding the imperfections out to the order of 400/1200 grit sandpaper (depending on how much you care about your buffing wheels) and then buffing the piece.

The Dremel buffing wheels also have the added advantage of being able to reach into places a 'normal' buffer could not - you can even use a pointed-tip Dremel felt attachment (with polishing compound...ick...) to reach inside of deep, or thin cracks.
Burf4 years ago
Use wet or dry sandpaper,  progressing from 400 grit down to 2000 grit, then  buff with a lamb's wool buffing pad and a high quality automotive polishing compound. You'll end up with a high-gloss finish.
You'll really need a powered buffing wheel, calico mops and polish.

You get the main marks out with abrasive paper, then work down to finer and finer grades, ending at least at 1200 grit wet and dry.

frollard4 years ago
Great question!

I would think it takes a fair amount of elbow grease - either from a buffing cloth or a power tool:  buffing wheel (large) or small dremmel sized.

Using a small amount of buffing/polishing compound used to remove swirls from car paint scratches, apply to the item, then buff the crap out of it.  Be careful not to overheat the object.  Some plastics cloud up when you heat them.

All about progressively finer and finer abrasion until the grooves you polish are smaller than the wavelength(s) of light so as to not distort the light shining through.