Spheretex

Can anyine tell me the advantages or disadvantages

of using this material in a canoe hull? Is it easier to repair than a foam cored boat?

Easier to repair, but because the
tiny little bubbles add thickness, the repair may be a bit more complicated than a repair on a simple laminate. Spheretex preserves some of the flexibility of conventional laminate. Spheretex is certainly not as light as a foam core, but by itself it contributes a kind of flexible girder strength. I have only one boat with Spheretex in the bottom and in side rib zones. The Spheretex zones are pretty stiff and have not broken. Non-Spheretex zones of the hull have taken minor damage.

Just so people know what we’re

– Last Updated: Oct-27-09 10:23 PM EST –

talking about, the following is filched from the johnrsweet.com catalog.

"Spheretex is a material made of woven E-glass fabric, volumized through the embedding of thermoplastic microspheres. The Spheretex micro-cellular structure provides volume with very low weight and high strength. It is used as a core material in FRP composites to form stiff, lightweight laminates. Spheretex provides a very strong light sandwich core, and is best utilized with a vacuum-bagging process."

The Spheretex listed in the catalog is 2mm thick, so you can see that it is much thinner than the typical foam core.

Consider johnrsweet.com for your boatbuilding needs. Now in the hands of Davey and Jennifer Hearn, but the johnrsweet.com address still applies.

Lighter, But…
SphereTex is a way to build a lighter but more fragile hull than the equivalent thickness of E glass fabric.



It has its uses in production, mid-range composites, but top end hulls will continue to use S glass, carbon, aramid, Vectran and, probably not wisely, Spectra.



I’d like to second the reference to Davy and jennifer Hearn - great folks, good materials and advice at good prices.

I would agree that the Spheretex may
be more fragile than an equivalient thickness of E-glass, but in my Millbrook, the Spheretex is essentially a stiffening beam between 2 layers of S-glass outside and one to two layers of Kevlar inside. The purpose of the Spheretex is similar to using a foam panel, to stiffen what would otherwise be an unacceptably flexible hull.

Likewise,
the layup I’m considering is a full carbon outer layer, then full layer of kevlar, full layer of sphertex and an inner layer of kevlar. The main reason for the carbon outer is for looks.