For all my builds I have been soaking the wood I intend to bend in plain water and this has been working fine so far. However in many other builds I have read the builder uses a mixture of water and either ammonia (Windex) or vinegar. Am I missing something? What does mixing these additives do that plain water doesn't?
Yep, ammonia softens the bond between the fibres so they can slide over one-another allowing the wood to be bent to a very tight radius without creasing. Only necessary if you need a very tight radius, otherwise plain water is good enough.
The ammonia works best as it actually softens the cell casing itself and lets it reform to the new position, then, when the ammonia dissipates it locks the wood into the new position just as if it had grown that way. There is some spring back if you use water.
Kind of like giving the wood a perm, right? Ok , thanks. I'll keep that in mind if I ever need to make any tight bends. Does the acid/ammonia affect the curing of aliphatic (TiteBond) any? IOW, should I make sure it's dried completely before gluing?
no special smelly additives needed - heat works. 200 deg F is the magic number. Boat builders use a steam box and steam the strips X number of minutes per inch thickness (I forgot the minutes number) then pull out the spaghetti bendable strip and shape it, clamp it, let it cool and dry.
I have a hot water tray - 3/4" wood squares tacked to a wood sheet and lined with Al foil, size about 40" x 9" to hold sheets of balsa. Balsa waiting in tray I boil up a pot of water, pour it on wood in tray, let `er sit for a few, then pull it out and strap it down to the shaped mold piece. Let her dry, trim and install.
For things like 1/16" or 3/32" turtle decks I soak the wood under running hot water from the sink tap, strap around form, let dry, trim and install.
A slight variation here - what I do is soak a sponge with plain water and apply it only to the outside of the piece to be bent. This way, the glue tends to work better since the inside surface is still dry (or relatively so at least). I've had excellent results with this method so far on pieces up to 1/4" thick. I've enclosed a shot from my current build with the results.