Restoring scratched plastic windows, dials etc... - UK Vintage Radio Repair and Restoration Discussion Forum

Marconi Man · 17th Apr 2007, 2:45 pm

I'm not sure whether this will be of any use to someone, but its a trick I found out by accident when I was given a digital multimeter which had a badly scuffed and scratched display window.

If you clean the plastic window and use some clear graphics adhesive tape - not sellotape, get it from an art shop or a graphics studio.
Carefully stick the tape over the plastic window and rub down... Most of the scuffing will disapear, but if you leave it overnight the effect is magnificent!!!

I assume the adhesive gradually fills the scratches as the result is a plastic window with a perfect finish and clear transparency to view through!

All you need is to trim carefully around the window and hey presto you have a new looking multimeter or whatever....

This method can be used on decorative trim as well as for dials and windows on instruments...

Hope it useful to someone! John.

Phil G4SPZ · 20th Apr 2007, 1:16 pm

Quote:

Originally Posted by Marconi Man

If you clean the plastic window and use some clear graphics adhesive tape - not sellotape, get it from an art shop or a graphics studio.
Carefully stick the tape over the plastic window and rub down... Most of the scuffing will disapear, but if you leave it overnight the effect is magnificent!!!

That looks a great idea, John. Is the clear graphics adhesive tape available under a recognised trade name or brand?

It could be a lot quicker than my more usual laborious method. I start with relatively coarse 'rubbing compound' used for car paintwork (or even fine-grade valve grinding paste for really badly scratched panels) and repeatedly polishing with ever-finer products such as 'T-Cut', finishing off with liquid Brasso. This works well and can restore opaque plastic cabinet parts too, although it is long-winded and you come close to losing the will to live after a while...

Phil

JHGibson · 21st Apr 2007, 5:33 pm

I have not tried it - it is just a thought - but perhaps you could clean a badly scratched plastic window and then spray it with a clear varnish which would fill in the scratches.
John.

Marconi Man · 21st Apr 2007, 7:47 pm

Hi, I suppose the original idea came from when I was trying to hide the electronic circuit from prying eyes, back in the 80s so I used a potting compound, unfortunately it was clear! so I sandpapered the outside to obscure the view of the inside. I then gave it a coat of clear varnish and all was revealed again!!!

So yes, varnish does work, but its a messy business and you have to be careful about whether its compatable also over-spray etc...

The tape I now use which transforms these old badly scratched windows into almost new condition is a highly sticky but more importantly, a very crystal clear graphics tape which does not yellow.

I've forgotten the name of it but most office stores have it as a graphic designer tape in 50mm wide reels, so it lasts for ever!
Hope that helps!

John.

Aretas III · 22nd Apr 2007, 5:47 pm

I use jeweler's rouge - an Autoglass man gave me some when he was changing my car window - it removes minor scratches on plastic very well.

Mike

17th Apr 2007, 2:45 pm	#1
Marconi Man Retired Dormant Member Join Date: Jun 2005 Location: Luton, Bedfordshire, UK. Posts: 9	Restoring scratched plastic windows, dials etc... I'm not sure whether this will be of any use to someone, but its a trick I found out by accident when I was given a digital multimeter which had a badly scuffed and scratched display window. If you clean the plastic window and use some clear graphics adhesive tape - not sellotape, get it from an art shop or a graphics studio. Carefully stick the tape over the plastic window and rub down... Most of the scuffing will disapear, but if you leave it overnight the effect is magnificent!!! I assume the adhesive gradually fills the scratches as the result is a plastic window with a perfect finish and clear transparency to view through! All you need is to trim carefully around the window and hey presto you have a new looking multimeter or whatever.... This method can be used on decorative trim as well as for dials and windows on instruments... Hope it useful to someone! John.

21st Apr 2007, 5:33 pm	#3
JHGibson Retired Dormant Member Join Date: Apr 2003 Location: Salt Spring Island, BC, Canada Posts: 368	Re: Restoring scratched plastic windows, dials etc... I have not tried it - it is just a thought - but perhaps you could clean a badly scratched plastic window and then spray it with a clear varnish which would fill in the scratches. John.

21st Apr 2007, 7:47 pm	#4
Marconi Man Retired Dormant Member Join Date: Jun 2005 Location: Luton, Bedfordshire, UK. Posts: 9	Re: Restoring scratched plastic windows, dials etc... Hi, I suppose the original idea came from when I was trying to hide the electronic circuit from prying eyes, back in the 80s so I used a potting compound, unfortunately it was clear! so I sandpapered the outside to obscure the view of the inside. I then gave it a coat of clear varnish and all was revealed again!!! So yes, varnish does work, but its a messy business and you have to be careful about whether its compatable also over-spray etc... The tape I now use which transforms these old badly scratched windows into almost new condition is a highly sticky but more importantly, a very crystal clear graphics tape which does not yellow. I've forgotten the name of it but most office stores have it as a graphic designer tape in 50mm wide reels, so it lasts for ever! Hope that helps! John.

22nd Apr 2007, 5:47 pm	#5
Aretas III Retired Dormant Member Join Date: Apr 2007 Location: Bury St Edmunds Posts: 1	Re: Restoring scratched plastic windows, dials etc... I use jeweler's rouge - an Autoglass man gave me some when he was changing my car window - it removes minor scratches on plastic very well. Mike