If I was to create a shape in CF using EF80 Flexible Epoxy Resin, once the bent shape is in position can I then reinforce it to a stiff strong form using your regular epoxy resin and reinforcement layers of CF over the EF80 Flexible Epoxy Resin?

Assuming you're not creating a structural part, then for sure you could. 

The part is going to be structural - the sides of a guitar body. I need to create a flexible strip of CF which is held in place by a body mold - the back of the guitar body is bonded on, then layers of CF added for structural stiffness. Will my proposed method work?

If you are intending to make a side strip and bond it on after then don't bother with the flexi resin, make a sheet from 1 layer of fabric and normal resin, it'll bend to your pattern then back reinforce after.

I wouldn't consider the sides of a guitar body as 'structural', certainly not in the essence that I intended it. They may be structural for the guitar, but they aren't high stress/high load parts like a chassis or crossmember haha. 

Thanks for the responses - you can see in this image the kind of layout I am looking at (my mold has more severe curves hence the need to flexible epoxy:

Try and get a copy of this book (number 3 in the series)

This is 1 layer of 200g carbon with IN2 resin. Flexible enough?

I wouldnt recommend EF80 for a guitar body.  EF80 is very flexible.  It is not a rigid epoxy it feels, once cured, more like a rubber or silicone in its texture and flexibility. Only when you add reinforcement does it stiffen up but it is still flexible but holds its shape to an extent.  You could make a moulded part using for example 2 or 3 layers of typical cloth using EF80 and the part would probably hold its shape out the mould but you would be easily able to deform and crush it by hand.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Looks very flexible - thanks for the pic. I think just the regular resin will do the job. Does brief heat applied with a hair dryer / heat gun give more flex temporarily?