Paul, Far and away better is to wrap the prepreg around a rubber
form, (hollow)
place it in a female mold with clearance to trail the fiber out the
trailing edge.
Then close the mold pressurize the rubber form and heat the whole
mess. The resultant
blade has a "single sheet" strength the trailing edge is trimmed and
you are done.
The layers of the trailing edge are clamped togeather and the leading
edge is continous.
My $.02. If I'm making the molds that is how I'll do it.
Bill Jepson

That sounds like a less labor intensive way of doing it.
What do you use for the rubber bladder Bill? How closely must it be
shaped
to the final planform of the prop blade? Can a section of bicycle
inner tube
be used?

Send me some sketches on this process. Would it help if a flat wood
insert
was placed in the rubber bladder the shape of the prop blade plan form?
Paul Lamar

Hey you guys, you are hitting on  an area of research for me right now
on helicopter blade construction...

Keep it coming, I appreciate the education.  Any thoughts on a good
mass production method, perhaps out of metal?

Hans

 
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