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BRE350Z
05-15-2009, 06:53 PM
Many of you know about the challenges I faced trying to strip a few model car bodies for Kevin. All of the models were painted with Tamiya lacquers and clear coated with Gunze B501 Gloss clear. Gunze B501 is a very "cool" clear coat and therefore safe for use on most finishes and when it dries it dries to a very hard finish which polishes out well. But removing it is another story.

The first model is a resin model therefore I did not want to dunk it in Super clean, etc so I gave it a liberal coating of EZ -Off (yellow can) sealed it in a plastic container (this stuff will eat through aluminum drip pans) and let is sit for 2 days. I expected it to come off easily under warm water - it didn't phase it.

I next tried 99.9% isopropyl alcohol, I might as well have soaked it in water.

On two other bodies I decided to try two different approaches, the first went into an ammonia bath - nothing.

The other into vinegar, thinking the acid might at least etch it - no such luck.

Knowing Windex will work on Tamiya paint I used a 1:1 mixture of concentrated Windex and water, nice clean windows but the clear was not touched.

Bob Downie told me he heard a 1:1 ratio of super Clean and isopropyl alcohol will pretty much strip anything - after 5 days nothing.

I found 2 methods that would work, the first involves media blasting using a small system available from Micro Mark, it goes through the clear but would take forever to clean an entire body.

The other is first using ELO (Easy Lift Off) now packaged under the Testors banner. I brushed a liberal coat on the resin body and by the time I was finished coating the car I could see the B501 giving way and some of the color starting to lift. After an hour I took the body and began scrubbing it under warm soapy water with a tooth brush. A second application removed a good portion of the color and primer. Final clean up was accomplished with the media blaster using baking powder instead of the aluminum oxide. It worked well but after a period of time it clogged the gun ( need something with a little more grain) A word of caution, if you use any type of media blasting be sure to wear a quality respirator and work either in a closed cabinet designed for this our with a proper ventilation system as this stuff goes everywhere.

I used the ELO to penetrate the clear on a second body and then soaked it in the 99.9% isopropyl alcohol and it worked fine, the trick is getting through the clear.

BobC
05-17-2009, 11:26 AM
Are we talking about "Tamiya lacquers" in the rattle cans? I've had real problems removing the blacks. Not sure that I've tried to remove other colors.

Remind me to never use the Gunze clear!!!!

BRE350Z
05-17-2009, 12:55 PM
I know two of the cars were painted in Tamiya lacquers from rattle cans, think one of the others was Testor's enamel. B501 is very good you just need to apply it in thin coats and let it dry, do not mask over it as it typically has a reaction with the tape. but if you need a good clear and not sure how the paint will react with other clears such as Tamiya it is excellent.

Wayne

Firehawk
05-17-2009, 02:39 PM
I had a similar experience with a clear coat I used on something about 15 years ago; I don't remember if it was Gunze or what... but I tried everything and nothing took it off, until I tried brake fluid and it came off in an hour, completely. Dried the plastic a good bit but the paint was gone at least.