30 minutes
Directions: Surfaces must be clean and dry. Joints should fit tightly. Apply a heavy spread of glue to the surface and clamp for 30 minutes. Do not stress joint for 24 hours. Remove excess wet glue with a clean, damp cloth
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30 minutes
Directions: Surfaces must be clean and dry. Joints should fit tightly. Apply a heavy spread of glue to the surface and clamp for 30 minutes. Do not stress joint for 24 hours. Remove excess wet glue with a clean, damp cloth
Member
The reason that your joint wouldn't come apart after an hour is because you wanted it to. In order to make the joint come apart after an hour, you simply had to want it to stay together. Of course, though, your desire would have to be sincere. Faking a desire to stay together would make it do exactly that. It's just basic science.Originally Posted by mreza Salav
Contributor
As an aside, many years ago I read an article about the useful life of various glues. Seems that the bottom line was: store/keep the glue at a moderate temperature and avoid extreme temperature swings. Also advised that after a year buy fresh glue, but I can not say if that still holds true for the more modern formulations. Of course in a commercial shop, the glue is constantly replenished, but for the week-end/amateur/part-time hobbyist, still might be something to consider. Seems to me that "fresh" glue has a better tack to it. I write the purchase date on the container and store it on a high shelf in the shop where it is warmer.
Something else I learned when doing a glue up: apply a light wash of water down glue to size the end grain. An patternmaker advised this, claiming it will seal the pores and prevent too much glue from being wicked up the end grain. "Dunno" if it is really true or not, but just one thing that I habitually do.
Member
The manufacturer's recommended clamp time for Titebond III (and original and II) with an unstressed joint is a minimum of 30 minutes to an hour. Not sure where the OP saw a recommended time of 2 hours. I take the clamps off panel glue-ups after half an hour all the time and have never had a failure. After 2-3 hours, I will run those through the planer and glue them together if needed to make larger panels. I do generally wait overnight before doing final surface prep to avoid glue line shrinkage. Franklin's website says to wait up to 72 hours for the wood that has absorbed moisture from the glue to shrink back to normal size to avoid shrunken areas near the glue line.
With respect to shelf life, I called Franklin's help line when I had some Titebond Extend that was over a year old. The gentleman I talked to was extremely helpful and gave me info on all of their glue's shelf life. Some have shorter lives because of the way they cure (cross-linking, if I recall correctly). Unfortunately, I don't remember the details, but the phone number is on the glue bottle if you have questions.
[OP]
Member
You are right ,it says it on the label between 30 min.to one hour,but their direction can be vague :
from TB3.com:
Moisture from the air and substrate fuel the reaction. The amount of moisture may affect the set time and cure time of the adhesive.
It good to know you have had no failure after half an hour,I'll keep that in mind .
Contributor
Sometime you have some scraps and feel like tinkering in the shop but with no project in mind, glue up some test pieces. Try to break one after 30 minutes, another after 1 hour, another after 1:30 etc. etc. Manufacturer's data is good, so is first hand experience.
Member
The outside surface of a glue "blob" will "dry" which impedes or prevents further oxygen necessary for the glue to fully dry and cure. That's the reason a glue blob is soft and squishable. It will take days, or maybe weeks, to harden. It's best to scrape off the glue and the thin residual will then harden.
Howie.........
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