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Made in us
Ragin' Ork Dreadnought




I have a few clear plastic cupola covers from the Sisters of Battle Immolator kit that I'm trying to make look nice, but the plastic is old and has yellowed some, and is generally pretty opaque and hard to see through. Is there a good way to clean it up and polish it so that it's more glassy, or a third party replacement piece I can acquire?
   
Made in au
Grizzled Space Wolves Great Wolf





You can polish scuffed up clear parts.

A headlight polishing kit from an automotive store is a good place to start.

I use my dremel with a foam circle cut from an automotive polishing pad and the automotive polishing compound. The trick is not to linger polishing one spot for too long, just short quick passes at a moderate speed. Too fast or too long spend in one spot can heat up the plastic and scorch it.

If there's deeper scratches, use sand paper first to remove the scratches and then polish it. Work from a low grit to a high grit, the highest you can buy (again, look to automotive stores, as they sell grits higher than what you can get in hardware stores). Use as high of a grit (large number, smoother paper) as you can, if you use something too rough you'll put even deeper scratches in to it which will also have to be removed.

If it's overly yellowed though, you might just have to replace the part.
   
Made in us
Gargantuan Gargant





Binghamton, NY

You need to physically remove the yellowing before you can worry about clarity. That means very fine abrasives. Along with Skink's automotive options, you can also buy plastic polishing compounds by the bottle (most hardware/home improvement stores have them, as does Harbor Freight) and use simple foam or cloth pads you may already have lying around (I usually start with a simple cotton shop rag).

I've actually had good luck using the finest polishing faces on a multi-grit nail buffer from the cosmetic department of a grocery store (this one had 5 grits - never touched the sanding ones, but the actual polishing surfaces were quite fine and buffed plastic to a reasonable gloss). Dedicated hobby products are also available, from scale model and gunpla companies, as well as the MicroMesh line of superfine sanding pads.

Whatever abrasive means you might use, I'd recommend applying a final gloss product to finish it off. A gloss spray might work, but I swear by the Future/Klear/PFC (the acrylic floor polish) dip. Airplane and car modelers have been using it for years on clear parts, even right off the sprue, to enhance shine and clarity, making parts appear more like actual glass, in scale. There are articles online about if, if you want more info.

With all of that said, whether it's worth the time and effort is up to you. If the damage is deep and the part is too fiddly (say, the domes have a bunch of ridges, like a 'metal' framework with small 'glass' panels in between), I might just try to get replacements. Check out bits sellers on Ebay. The parts might be pricier than you think reasonable, but compared to the cost of tools/materials and all the time spent, it may prove the better deal.

The Dreadnote wrote:But the Emperor already has a shrine, in the form of your local Games Workshop. You honour him by sacrificing your money to the plastic effigies of his warriors. In time, your devotion will be rewarded with the gift of having even more effigies to worship.
 
   
Made in us
Ragin' Ork Dreadnought




Thank you both!
   
Made in ca
Fireknife Shas'el






Or you could just paint it gold.

   
Made in au
Grizzled Space Wolves Great Wolf





 oadie wrote:
Whatever abrasive means you might use, I'd recommend applying a final gloss product to finish it off. A gloss spray might work, but I swear by the Future/Klear/PFC (the acrylic floor polish) dip. Airplane and car modelers have been using it for years on clear parts, even right off the sprue, to enhance shine and clarity, making parts appear more like actual glass, in scale. There are articles online about if, if you want more info.


I think that comes down to personal preference, I reckon "glass" looks best when it's well polished, but not dipped in Future. The floor polish gives it a look that doesn't look scaled glass-like to my eye.

But everyone is entitled to their opinion. I prefer well polished but not dipped, others rave about the floor polish

Either way, if you do want that gloss look, I don't recommend a gloss spray as it's almost impossible to avoid some level of either graininess or orange peel which is very noticeable on clear parts, the acrylic floor polish self levels itself in a way gloss spray does not.

I forgot to mention in my previous post, Tamiya polishing compounds also work great for polishing canopies, but they're not cheap. They make 3 of them, coarse, fine and finish. If you're doing what I said (using a dremel with a foam pad) then you probably just need 1 or 2 of the compounds.

I was watching a video of someone doing a car model, if you fast forward to 17:00, he polishes the paintwork of the car in a very similar way to how I polish my canopies, but he uses cotton polishing pads. Maybe his polishing pads are different, I found the dremel ones too harsh which is why I swapped to foam ones (which I cut myself from larger automotive polishing pads). Notice that he starts polishing by hand but eventually gives up and swaps to a rotary tool It's definitely possible to do it by hand if you don't have a dremel (or similar), just a lot more work.

https://youtu.be/RxDp3EyrBtc?t=1023


This message was edited 2 times. Last update was at 2020/01/01 02:57:04


 
   
 
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