Now fabricate a bottom plate out of 3/16" aircraft ply. You can use 1/4" if you wish, but I have found 3/16 to be more than sufficient. Just don't make the mistake of using lite ply, or it's gonna suck to be you on your first landing.

Use epoxy and glue this piece on, and use a weight to make sure you have total contact. If you have gaps, it might seperate later.

(cont)