Removing scratches from plastic speaker cabinets

I am providing some background music for a holiday party I'm attending (not working) tonight. I was just going to bring my JBL EON Compact but decided I would bring a 2nd small powered speaker just in case I need it. I have a ~20 year old 10" powered speaker that rarely comes out of hibernation that I decided to take. This is the speaker I would lend out to people that just needed a PA for events. It has no bag and it had accumulated a few scratches over the years. I wanted to see if I could do something about the scratches. My approach worked in greatly reducing the scratch.

I used a propane torch and moved it VERY quickly back and forth over the scratch. This slightly melts the edges of the scratch and restores a little of the cabinet's luster. If you hold the flame too long, the plastic will bubble and look worse. I first tried the approach on the bottom of the cabinet where any screw-ups wouldn't be visible. This technique didn't fully remove the scratches but it greatly reduced their visibility. I should have taken some before and after pics.

This particular speaker didn't have a smooth plastic finish to start with. I'm not sure how well this will work on a perfectly smooth cabinet. I recommend experimenting with the bottom of the cabinet. There are always scratches near the speaker pole hole that no one sees.

MIXMASTERMACHOM said:

So Dr. Einstein what would you suggest he use?

Click to expand...

I think he was saying that I should simply torch the 20 year old speakers. However, I'm not there yet. I pushed them much harder than I expected to and they held up well and still sounded pretty good.

LittleTreeGuy said:

I always like the DIY stuff like this. Not that you still need anything, but I wonder if the roll-on or rattle-can version of the truck bed liner spray would stick to a plastic cabinet? If so, that may be an option.. just have to hope it wouldn't flake off. But it would supposedly be durable, and it has that "not-smooth" texture to it like most speakers already have.

Click to expand...

My guess, if you were to try that, you would get better results by scuffing up the cabinet before application. This cabinet was definitely not to the point where I would consider that. In fact, if it was that bad, Bob's suggestion to torch might be more fun.