Scratch in perspex

rgmwa · #1 12-12-2014, 06:56 PM

I have a fairly deep scratch about an inch long in my canopy. Must have accidently dropped a screwdriver or something on it during the build, but only recently noticed it. Is there a recommended filler or repair method, or best just to leave it alone?

eddieseve · #2 12-12-2014, 09:37 PM

There are various polishing kits available form either Vans or aircraft spruce that can help to remove or reduce the scratch.

If it's not in your field of view the simplest thing can be to leave it alone.

Cheers

AJ85WA · #3 12-13-2014, 02:56 AM

Hey mate

How are things coming along?

Definitely +1 for the scratch removal kit from vans.

Step by step video below.

http://www.eaavideo.org/video.aspx?v=2616988646001

rgmwa · #4 12-13-2014, 03:19 AM

Thanks guys.
AJ, the plane is down at Serpentine. First engine start was last week, but I'm caught up in CASA's W&B issue at the moment. I've done the supplementary MPC course, but am waiting for CASA to formally amend the rules. Apparently they're focussed on the Jab issue at the moment, but apart from that, I'm pretty much ready to fly.

PCHunt · #5 12-13-2014, 12:37 PM

One thing to be aware of in trying to remove one larger scratch, especially a deep one: As you tediously sand away to remove the scratch, you are making a small depression in the surface of the plexiglas. That becomes in effect, a small "lens", and can result in distortions, or "waviness" as you look through it.

The US Navy tried repairing F-4 Canopies that had been scratched, and made them MUCH worse, because of the waviness. More than a few had to be replaced after the "repair".

Use caution, and try it on a piece of scrap plexi first.

rgmwa · #6 12-13-2014, 03:04 PM

Thanks Pete. My main concern is whether it would initiate a crack over time.