Epoxy and thickeners
We buy our high quality 2:1 marine epoxy in bulk for use in our workshop so when we started selling boat kits it seemed natural to decant it into jugs for our kits. Having our builders work with the same epoxy we know and trust ensures you have the best experience. We have two hardener options “slow” and “fast”. If you are working in a colder shop consider the fast. You’ll still have about a half hour of working time. Or get a mix (e.g., 3 gal kit with 1/2 gal of slow and 1/2 gal fast). Be sure to check out our article on the basics of working with epoxy.
Thickeners
There are two main thickeners typically used. A “structural thickener” (cabosil) and a “fairing filler” (microspheres). Unfortunately both come as a white powder but we found long ago that adding wood flour (a very fine hardwood dust) to cabosil makes it smoother, easier to apply fillets and turns it a much more pleasing brown color which is a close match to coated Okoume wood so if you finish your work with varnish it won’t be jarring to the eye. We call this our “B&B Blend” thickener and you can identify it with its light brown color in the bag. This is your structural thickener used throughout the build for everything—fillets, bonding, glue-ups, etc.
Microspheres on the other hand are microscopic glass bubbles which displace epoxy when mixed in, creating a fluffy, spreadable, easy-to-sand fairing filler that is used to fill glass weave, fill in low spots and fair the outside of a surface (not a structural filler). It’s easier to sand and not much is needed for a typical build compared to the cabosil blend.