me&z wrote:Glad you liked it.
I thought ghcoe's hints on using Great Stuff as a glue and the need to clean the flashing were worth giving it new exposure.
I never asked but was always curious if there were any downsides to metal flashing. Condensation in very cold weather or issues with thermal expansion and the glue joint were the 2 that I thought of. (Sorry ghcoe: Ooccupational hazard. failure mode and effect analysis just becomes part of your thought process during the design stage after a few decades.)
There is a thermal difference in expansion and contraction. Really the only problem is where I butted to pieces together. With expansion and contraction I have a area that bubbles out a bit. When it is hot out it goes away.
In my #2 build I decided to move the flashing to the outside of the canvas so I did not have as much fairing to do. In the process of the build though, I found that by laying the canvas over each other along the edge and using full strength TBII it made for a pretty solid edge. I still think adding the flashing to the outside of the canvas if you need more protection is going to be better and easier to do for most builds.
Flashing for hard points, I think, still will need to be installed under the canvas. The canvas adds a lot of holding power to the flashing and the flashing gives you a hard point to pop rivet/screw into. The two have to work together though for a strong mount. George.