Author Topic: Help needed polishing scratches out of plastic!  (Read 7805 times)

Offline Skylark

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Help needed polishing scratches out of plastic!
« on: February 20, 2017, 09:46:56 PM »
The turntable guys seem to have mastered polishing turntable lids, what's the secret?

I can get plastic glossy but it will still have a lot of residual scratches, it's as if plastic is so soft the polishing process itself introduces scratches no matter how careful or fine you go. I'm basing this off machine polishing with a cloth or felt mop.
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Offline skollie

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Re: Help needed polishing scratches out of plastic!
« Reply #1 on: February 20, 2017, 10:27:46 PM »
Hi Skylark

If you want perfection, speak to Alternativeroute. It's a tedious job and I've seen his work which is very good.

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Offline KenMasters

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Re: Help needed polishing scratches out of plastic!
« Reply #2 on: February 21, 2017, 06:03:44 AM »
I use a Body Shop four step nail buffer for that sort of thing, works brillianly for buffing out small scratches on most soft gloss surfaces:



Though more for isolated scratches rather than a wide area - for that purpose I use car polish and a cloth.
« Last Edit: February 21, 2017, 06:08:29 AM by KenMasters »

Offline trevorhd

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Re: Help needed polishing scratches out of plastic!
« Reply #3 on: February 21, 2017, 06:54:48 AM »
For heavier scratches you use the very fine sandpaper used for polishing paint on cars. I think it is 2000 grit and then finish off with brasso and then silvo.

Offline Larry

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Re: Help needed polishing scratches out of plastic!
« Reply #4 on: February 21, 2017, 08:24:17 AM »
I use a Body Shop four step nail buffer for that sort of thing, works brillianly for buffing out small scratches on most soft gloss surfaces:



Though more for isolated scratches rather than a wide area - for that purpose I use car polish and a cloth.

Do use it dry?

Offline Timber_MG

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Re: Help needed polishing scratches out of plastic!
« Reply #5 on: February 21, 2017, 08:31:39 AM »
Flame polishing may be one of the tricks too. For the best flame polish, Rodney Gold.

Offline KenMasters

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Re: Help needed polishing scratches out of plastic!
« Reply #6 on: February 21, 2017, 09:15:49 AM »
Do use it dry?

Yip, just like that. I use them to fix up the bathroom basin once in a while as well (gets a bit scuffed and dull in one spot from rinsing off my razor). They're not very hardy though, the coarsest side wears down pretty fast.

Offline thenoizeguy

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Re: Help needed polishing scratches out of plastic!
« Reply #7 on: February 21, 2017, 10:41:46 AM »
I get good results finishing with Maguires Plastix Polish on a slow sponge wheel and then buff off. That stuff is used for car headlights.
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Offline Larry

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Re: Help needed polishing scratches out of plastic!
« Reply #8 on: February 21, 2017, 10:49:20 AM »
Yip, just like that. I use them to fix up the bathroom basin once in a while as well (gets a bit scuffed and dull in one spot from rinsing off my razor). They're not very hardy though, the coarsest side wears down pretty fast.

 :thumbs:

Offline Rodney_gold

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Re: Help needed polishing scratches out of plastic!
« Reply #9 on: February 21, 2017, 12:49:48 PM »
Only real way to do this is to sand with fine waterpaper and successively polish with finer and finer rouges and mops till you are using a swansdown mop with no polish

Dont use brasso or silvo .. they contain solvents etc and can lead to stress cracking on certain types of acrylic .. use Maguires type stuff

flame polishing uses a very high  heat flame that is the product of splitting water into Hydrogen and oxygen and burning it. Its a very narrow flame used mainly for cut edges and it is a balancing act of enough heat to melt saw or milling marks and heat deformation of the acrylic.. not all plastics can be heat polished .. but large surfaces are very difficult or impossible to do this way .. linger a little too long and you damage more than polish..
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Offline Steerpike

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Re: Help needed polishing scratches out of plastic!
« Reply #10 on: February 21, 2017, 05:22:01 PM »
Dont use brasso or silvo .. they contain solvents etc and can lead to stress cracking on certain types of acrylic ..

^^^^ VERY good advice.
Brasso from 10 years ago is good on plastic; then they added some petroleum solvents and took out the ammonia. Now it is destructive to many plastics. ( And it doesn't really clean brass anymore either, so no point in buying it.)

Offline Tzs503gp

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Re: Help needed polishing scratches out of plastic!
« Reply #11 on: February 21, 2017, 09:17:49 PM »
See if you can find some Menzerna polishing paste. Northern Bolt in Midrand sells it. I use a buffing wheel in a hand drill at slow speed, and get brilliant results on polycarbonate.

Offline Skylark

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Re: Help needed polishing scratches out of plastic!
« Reply #12 on: February 21, 2017, 10:35:31 PM »
Thanks for all the tips.
See if you can find some Menzerna polishing paste. Northern Bolt in Midrand sells it. I use a buffing wheel in a hand drill at slow speed, and get brilliant results on polycarbonate.
Which one exactly, they make a huge range?
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Offline Skylark

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Re: Help needed polishing scratches out of plastic!
« Reply #13 on: February 21, 2017, 10:37:04 PM »
I get good results finishing with Maguires Plastix Polish on a slow sponge wheel and then buff off. That stuff is used for car headlights.
What prep do you need to do though? How deep can the scratches be if you just use the sponge and Plastix?
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Offline prajayn

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Re: Help needed polishing scratches out of plastic!
« Reply #14 on: February 22, 2017, 07:17:42 AM »
Check out this professional detailer - there's a couple of videos with regards to polishing plastics.

https://www.youtube.com/user/AMMONYCdotcom

Brasso worked great but is too abrasive. I used meguairs ultimate compound when I had a similar issue but there's plenty products to choose from.

Needs lots of elbow grease though if you don't have a machine.