Thanks so much!no worries; the thread has been growing a bit. I can't even remember what I posted before haha. The ones in this thread are my very early builds, but the techniques used are essentially the same. For Kermit, I made the heads foamless, so the shape is generally the hand when in use. The removable foam inserts I cut for them are for when on display only.
You're correct, I attach the mouth plates to the head using contact cement; a part of the pattern folds over onto the mouth-plate, as seen below. The notes were from very early on when my pattern was not as refined, so I had to do some test fitting and trimming. The photos below are of my later pattern, which I was able to get to fit without trimming, but the method of attachment is more easily seen here. I know some people have also tried sewing the fabric to the mouth plate and then gluing the rubber parts in later from behind, although based on the kermit I saw in an exhibition, it appeared to be glued (edge of the fabric was visible). But either works. :
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