Drying my nylon helped out a lot.  I was a bit impatient so it still has a little moisture, but it is good enough. 

Each set of 4 petals only consumes 1g of filament as they are 0.15mm thick and a single layer, so I'm not worried about having to try a bunch of times to get it right. 

I took my failed prints, and stacked them, to prove the concept.  Here it is.

I have not succeeded in getting these to hold the petal curve yet.  Just crushing them curves them in one dimension, but the other petals were curved in two to look right.  Heating them goes almost straight from solid to too soft. 

That is going to be the hard part, and the reason they look overly 'flat' here.

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I haven't been able to heat mold these with any good consistency.  

I believe the dual curve is required to reduce the force required to close the rose.  Right now the required force is high enough that a servo would struggle to do it.

Working on it..

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