: I'm running out of wood flour. I'm unlikely to have enough to fillet and tape
: the inside shear seam. I've already done it in the center of the boat, but
: am waiting to cut the hatches to complete the seams in the two ends. Do I
: need wood flour for this, or can I use micro balloons? I was thinking of
: getting micro balloons for the end pours and wonder if it can do double
: duty. Or doesn't it have the bond strength needed for a shear seam fillet?

I use colloidial silica mixed in epoxy for filets on my bulkheads and shear seams. I've not used microballoons but it's my understanding that they are fine for this application (and a whole lot cleaner looking than epoxy thickened with wood flour).

As far as your end pours go, I form a cedar "plug" that takes up most of the volume, requiring a minimal amount of epoxy to complete the fill. This method reduces a fair bit of weight but you do need to ensure that you do a good job of sealing the wood when you drill your toggle holes.

Dan

http://www.westcoastpaddler.com

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