Re: carbon fibre driveshafts

[MSV96 <MSV96@aol.com>]

In a message dated 1/27/98 dave.eaton@minedu.govt.nz writes:

<< i've used carbon fibre in a number of applications (canoe's, paddles and
the
like).  in no case would you *ever* find any amount of flex without the
destruction of the article.  carbon fibre (when properly applied and cured) is
immensely stong in twist and compression. >>

While I am certainly not an expert in the lamination of carbon fibre items (I
think there is a lister who is...maybe he can comment on this), I do have some
experience using items made of it in sailing and bicycling. On sailboats,
masts, spinnaker poles, booms, etc. are often now made this way. I own a
bicycle made nearby (Kestrel) which is carbon fibre. While it is true that in
certain directions carbon fibre laminations will shatter or break prior to
bending, depending on the type and direction of the laminations flexability is
designed in. On sailboat masts, mast bend is controlled this way (with the
help of standing rigging in most cases). Kestrel makes a bicycle frame that
has no seat tube (500sci ?...not the model I own) where each frame size has
exactly the same amount of verticle flex (for shock absorbtion) designed in.
In other words what Phil describes is certainly possible with these materials
within reason. A full turn of flex in a driveshaft sounds a bit extreme to
me...but again, I'm not an expert...just an end user.

Mike Veglia
87 5kcstq