Expanding our composites knowledge, todays reading discusses Waxed and Unwaxed Resins.
Simplifying, imagine Waxed Resin being synonymous with Finishing Resin. Curing to a dry, non-tacky surface in 4-6 hours, Waxed Resin is intended to be used when working with our finishing layer. The science behind it is interesting, but for our purposes, a detailed description of the how, and why is not really necessary. What we can be sure of is that the addition of wax allows for our composite to cure in a way that allows for secondary applications such as sanding, which would then allow us to paint.
With a cure time of 4-6 hours, this forces us to finish our composite in one day. Maybe we’re not that quick yet, or busy reading the Composites Canada articles; either way, Unwaxed Resin provides for us a solution.
If we have multiple layers of fabric that we wish to laminate, as well as a bit of time on our hands, Unwaxed Resin is preferable. Comparisons and visuals usually make learning a bit easier, so let’s try and do that. In Waxed Resin, the wax provides a barrier between resin and air; picture this, resin → wax → air. In the Unwaxed Case, we have resin → air. This direct resin to air contact allows for our composite to remain tacky, enabling for the addition of multiple layers with greater adhesive strength between them. As above, Unwaxed Resin is synonymous with Laminating Resin.