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I did some adhesion tests with popsicle stick sets.
THe test was to see what adheres to dried titebond.
Four adhesives were tested for adhesion to Titebond:

Titebond to Titebond

Epoxy to Titebond

Stewmac BindAll to Titebond
Fish glue to titebond

Adhesion area of each stick was sanded with P220.
One stick of each set was coated with a thin layer of Titebond (1/2" of end of stick). Titebond allowed to dry for 48 hours. The second stick of the set was glued (1/2" end of stick) to its Titebond mate, then clamped (small plastic spring clamp) and allowed to dry 48 hours.

Fish glue adhered very well to dried Titebond, the wood failed before the bond. The others separated very easily (fail). This is very useful when making repairs to an area where you can't remove all the Titedbond residue (or dried Titebond resides in the grain).

I do a popsicle stick adhesion test before I use my glues if they are over a year old.

TITEBOND DATE CODE
SOURCE http://www.titebond.com/resources/use/glues

How Do I Read The Lot Numbers?

Current format for product made after 1/1/2019: Ayymmddbbb

The first letter is A for made in America, the first two digits after the A is the last two digits of the year of manufacture, the fourth and fifth digits represent the month, the sixth and seventh digits represent the day of the month and the last three digits represent the batch number for that day.

Example: A190615023 – This material was manufactured on June 15, 2019 The new code is: AYYMMDDNNN where: A=made in America YY=year manufactured (i.e., 19=2019) MM=month of manufacture (i.e. 01=January) DD=day of the month manufactured (i.e. 15=15th) NNN=a number indicating the batch

_________________
Measure Twice,

Karl Borum

It may, but not very well. With the sanding you are creating a mechanical bond, akin to doing multiple layers of automotive clear coat, but sanding between the coats to give the coats something to bite into.


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Dried Titebond was not sanded before adhesion with fish glue (test stick WAS sanded before Titebond).
YMMV, would be interested if anyone gets same or different results.

Why would this be of interest? When regluing a loose bridge (or FB extension, or braces etc.), where torn fibers are glued back in place on the top, Titebond might be a better choice than CA to glue down fibres, if followed by a Fish-Glue glue up.

I should know better than to post about adhesives

_________________
Measure Twice,

Karl Borum

Interesting data, but I still wouldn’t advise anyone to use fish glue for a critical component like the bridge. There are multiple reports of spontaneous fish glue failure in stressed applications, both on this forum and other instrument building / repair forums. Too many reports for it to be coincidence.