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Transparent floor - Lexan VS Plexi Vs ?

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Well-Known Member
Nov 25, 2007
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Hi everyone,

I know the pros and cons have been discussed already in various topics but despite a thorough look with the search function I could not get a clear picture...
My S1S has what is I believe a Lexan belly. Sadly between recurrent fuel spray from the vent line and less than ideal installation (I suspect too tight holes), it is badly cracked and will need replacement. The said panels just replace the equivalent alum panels from the plans (I-224-33 & 28, because you asked :p ) and therefore include bends.

The questions are therefore as follows :

-> What material would you suggest ? From what I got Lexan will bend easily, but will crack fast with fuel spray ; Plexi will be a bit more fuel resistant, but hard to bend without cracking (hot air gun ?) ; obviously both will crack if holes don't allow enough play or are drilled with too sharp bits...

-> What thickness ? The current ones looks far too thick and heavy to me. Something like 1/8". But maybe that's what is needed ? For ref the alum there according to the plans is .032

And of course more than happy to learn about any other option I may have not considered out of ignorance !

Thanks for the help !


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