Jim Kirby wrote: I still use epoxy for fretboards (usually T-88), but I did have to learn to not over-clamp. Epoxies with long open times can squeeze out of a joint easily. I'm surprised to hear someone say they think you can't starve an epoxy joint. Early on, I had two fretboards almost spontaneously fall off of necks. (Beginner's not-luck.) I'm pretty gentle on that joint now.
You may wish to review that earlier post and note the qualifier - coating both surfaces with epoxy is a necessary step, and avoiding the sort of truly ridiculous clamp-ups sometimes seen.
If those surfaces can be coated successfully (105/205/206 shows near-immediate evidence of poor surface prep if you are paying attention), the joint will be very difficult to starve. In point of fact, slow-cure, lower viscosity epoxies will continue to squeeze out even with light clamping forces until the bonding surfaces are in or very close to contact. The epoxy left in the joint - both in micro key-ways (mechanical binding) and some wetting of the surface layers of wood cells in the outer thousandth of an inch or so of wood (both mechanical and Van Der Waals inter-molecular bonding) - is more than adequate.
On clamping, we usually used 4-5 Bessey F-style clamps, and the most that I could generate with my hand strength was still less than 50% of the rated maximum (~1300 lbs), as measured with a device in a local university testing lab. And before you ask, a visit to the lab was a tolerable price to pay for help dropping off a pair of bicycles with my niece, who was at the time attending that university. That I had to endure the usual frat boy strength contest (the 20-something lacrosse-playing grad student escorting us won handily, exceeding Bessey's numbers and permanently damaging the clamp) was fully expected.
Per Mr. Stock, who has worked with structural and surfacing epoxies in marine and aircraft for what would now be five decades both as craftsman and engineer, the biggest issues with epoxy joints are a) failure to fully wet out both surfaces prior to closing the joint, and b) poor surface preparation with resultant low surface energy which prevents the sort of inter-molecular bonding which provides much of the bond strength associated with these joints. Per a text exchange this AM, he does agree that the joint may be starved, but is far less likely when a) and b) above are avoided and the usual 4-5 clamps are used per his method. To your point, he suggested that every joint failure postmortem (in normal use) to which he had been party included evidence of either a) or b) above.
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