Need help cleaning NOS plexiglass canopy

[hawkeyepoole]

The B-26K/A-26A restoration team is in possession of two brand new bubble canopy sides for the radio compartment of the aircraft. They are both covered top and bottom with a sprayed on protectant that has over the years, become part of the plexi.

I have a part of one canopy soaking in water overnight, but don't see any change. I have access to every solvent known to man, but am not willing to risk damaging these bits of unobtanium with an experiment.

Some of the restoration guys worked in Iraq/Afghan and said helicopter plexi comes covered in something similar, and they sometimes break it off in sheets. Trust me, this isn't coming off in sheets, or even in small flecks without me damaging the plexi by scratching it.

Suggestions? Anybody dealt with this before? Feel free to email me directly as well as post suggestions here.

[Bill Greenwood]

Rohm (Sp?) and Hass are the major makers of aviation plexiglas; try finding them on a website and calling or writing for info. Who knows if they made those pieces in the past, or the protective cover?
There also may be someone at the Garber restoration facility of Smithsonian Air and Space that has ideas. Also at EAA?
Don't use any alcohol on it.

[airknocker]

LP Aero has always been helpful with plexi questions:
http://www.lpaero.com/

[shrike]

I used to be a sign-maker and we often worked with old plexiglas. Here's some of the tricks we used - please use caution and test on the panels you're replacing to be sure that the formulations are the same and/or compatible.

Disclaimer out of the way, plexiglas isn't affected by lacquer thinner (disclaimer 2 at least any in the last 20 years). Get a nice fresh can and soak the cover sheet. You can even soak a rag and let it sit for a while to soften the glue holding it on.

At you local upholstery shop you can find carpet padding that looks like it's made out of every scrap of fabric known to man. As nasty as it looks, it wont scratch even fine and fragile surfaces (check it for foreign bodies first - disclaimer 3)

Avoid any cleaners with ammonia. Ammonia will dissolve acrylic resins and cloud the surface. It is handy for cleaning up acrylic paints

[T-28mike]

I have run across the same covering on previous issues of those parts (and others), and have had reasonable sucess with a hot water pressure washer. Disclaimer (as above) watch the temperature . Hot water, not scalding (plex starts to get real soft around 180*) water. The heat tends to soften the protective cover and the pressure "peels" the coating.

[valdez25]

I bought NOS landing light covers for the T-6. Spent the better part of 2 days trying to clean the goo off of them. Tried everything, stoddard solvent, hot water, and the only thing that worked was my fingernail. Someone suggested I try rubbing alcohol and in 2 minutes they were clean as a whistle.

[skymstr02]

There is also a product, that can be purchased at your local hardware store called "GooGone". I used thatt on some plexi windows for a Navion that was about 40 years old. Its a naptha based product, and won't harm the resins in the plexi.

[hawkeyepoole]

Thanks to all for the suggestions and comments. While I was asking the question I had a part of the canopy soaking in a bucket of water overnight. Seems the coating softened, turned opaque and I was able to fingernail some pieces off.

I now have most of it soaking in my never-used jacuzzi tub in the master bedroom. Wife loves it. I'm going to leave it for several days and see what happens. If it gets really soft like I hope, I'll be able to pull the coating off in large sheets, and then just polish the canopy.

I'll keep all updated

[hawkeyepoole]

Thanks to all for the suggestions and comments. While I was asking the question I had a part of the canopy soaking in a bucket of water overnight. Seems the coating softened, turned opaque and I was able to fingernail some pieces off.

I now have most of it soaking in my never-used jacuzzi tub in the master bedroom. Wife loves it. I'm going to leave it for several days and see what happens. If it gets really soft like I hope, I'll be able to pull the coating off in large sheets, and then just polish the canopy.

I'll keep all updated

[Tinker51]

These updates you promised, update on the success of canopies or update on how mad your wife is because that piece of "junk" is still in the tub?

[tom d. friedman]

try a product called 210 plus. it's a plastic / plexi scratch remover. there is also a sister product 210 plus polish. both are boating products but they work fabulous on any plexi. you'll find it at any good boating store. they cost just under 15 dollars, or i can send you some + shipping if you can't find it. it's the bomb, i sell the heck out of both!!

[Dan Jones]

I have HEARD that aircraft hydraulic fluid (5606) has successfully been used for this but I haven't tried it myself.