Greetings,

 

Marv's question about cleaning masking tape residue off an airplane window reminded me that I should post the results of my test.  As we all know, the Lancair assembly manuals warn against getting acetone on the canopy or side windows, with dire consequences sure to follow.

 

Out of curiosity, I took a piece of scrap Legacy aft window, left over after cutting it to size, and soaked it in acetone for a minute or two.  For good measure, I also rubbed the acetone into the surface of the acrylic.  I then set it in the sun. 

 

After more than a year of sun exposure, it looks exactly like it did before the stress test.  I had expected crazing at the least, but it is totally unchanged.  I would never recommend intentionally using acetone on the canopy or side windows because lots of people lots smarter than me say not to do it.  But if a person accidentally spilled a little on the canopy, it seems that it might not be the end of the world.

 

On the other hand, people do report crazing problems.  I still have the test sample.  Anyone want to suggest a different chemical for me to try?  It's a shame to leave a good piece of scrap go to waste.

 

Here's today's photo of the sample:

 

 

 

Dennis Johnson

Legacy #257, now flying