Heating wood before epoxy/varnish/finish

[Thorne]

I just noticed a few common processes in the recent "shop heating" and Bob S.'s old "7-ft oar" threads -- the concept/process of heating both wood and epoxy/varnish/finish and applying it hot, letting it 'cool into" the wood.

Bob's use of unthinned epoxy at relatively high temps for hardening the surface of the cedar oars is particularly interesting.
http://www.woodenboatvb.com/vbulleti...even-foot+Oars (http://www.woodenboatvb.com/vbulletin/upload/showthread.php?t=3422&highlight=Simple+Pair+Seven-foot+Oars)

One of the shop heating posts mentioned this process to reduce bubbles in varnish (I think it was varnish).

I'm not fishing for trouble or trying to start a firestorm of controversy -- just very interested in the idea of heating the wood and finish to increase chemical penetration, surface hardness, and possibly the quality of the overall finish/varnish-lifetime/protection.

[JimD]

Can't say much about hardness. Penetration to a point I suppose because most of the stuff we put on our wood is less viscous when warmer. As for the problem of outgassing, yes, absolutely, preheating your shop or at least your wood considerably makes a big difference. The late Robb White may well have pioneered this method. He used it extensively. Now so do I whenever possible.

[pipefitter]

I remember a wood carver that used to make those cypress slab clocks and furniture as an aside to his carving and for the tourists and he coated them with envirotex(epoxy) and would use the heat from the flame of a propane torch to get the bubbles out of the finish. Also,when wrapping custom fishing rods when the flex-coat (epoxy) would trap bubbles of air from the thread,you could exhale warm breath on them and also get rid of the bubbles.Epoxy sure does flow well in the summer down here at 80 and above but it also sets up quickly. When applying fibreglass,there's a point of the cure that when even though the resin still seems thin,that it wont wet out cloth as effectively as when you start so you may need to adjust to smaller amounts of resin if you warm the resin to above room temps initially.Maybe the heated surfaces extend the wet out time enough to counteract the hot cure rate.