Heatgun to get scratches out of acrylic hatch ?

[SvenG]

Despite lots of "be careful not to damage" warnings, a local worker varnishing the topside teak managed to put some ugly scratches in one of the acrylic hatches.

I know that heat is used to smooth out some professionally cut acrylic and I saw references to using a heat gun to get out scratches. Our acrylic is 3/8" so I assume one could heat the scratched side without causing the whole sheet to sag.

I've used plastic polish for plastic portholes but it was not very good at removing actual scratches.

So, any experiences with heatgun treatment to smooth out scratches or am I looking for trouble if I try it ?

Thanks,



-Sven

[bstreep]

Sven,

I'm not too sure about the heat-gun thing. You risk ruining the hatch.

I'd polish them. Start with as heavy a sandpaper as required to remove the scratches. Then move up in grit (finer) as far as you can find. Then use acrylic polish to finish. We use the Novus 123 system. This WILL work, but how much work it will take will depend upon the depth of your scratches.

[GordMay]

Google Acrylic Scratch Remover

[capt-couillon]

Funny you should ask... Just in the midst of restoring a 80s vintage AeroMeter compass with an acrylic bubble that was so degraded you couldn't see the color of the card. This Kit is used to restore acrylic aircraft windscreens. But being a cheapskate, I went with what I had onboard. 1000, 1500, 3000 grit wet dry sandpaper, and a final polish with toothpaste. All of the kits contain some sort of a liquid to apply as a last step. This is due to the fact that even the finest polishing compound leaves some scratches and a hazy finish. The liquid fills those voids and leaves a glass smooth surface. Usually some form of urethane/acrylic clear coat.
Best I have found is this. Automotive 2 part acrylic clear coat. Puts another layer between the world and your plastic. Downside is you have to use the entire can within 48 hours, but a coat on your good hatches and other plastic parts will use the excess. Not cheap, but harder than the hinges of hell.

[SvenG]

Thanks for the answers.

I did contact TAP Plastics where I'd bought the acrylic sheets and they did not recommend using a heat gun. While a heat gun can give a gloss surface back by melting the top layer the heat will also make the acrylic shrink so we could end up with an even bigger mess.

Here in La Paz (Mexico) we found Meguiar's Mirror Glaze 10 Clear Plastic Polish but it is so liquidy that I'm not sure it does anything but clean the surface

With all the auto parts places around here I'm sure there must be other products available too, maybe including the suggested ones. We'll keep looking and do the wet sand paper if we find nothing else.

Thanks again.



-Sven