|Forum topic by richgreer||posted 779 days ago||975 views||0 times favorited||17 replies|
779 days ago
With respect to glues, we probably all know what open time is. A longer open time gives us more time to arrange pieces for assembly before the glue dries.
I’d like to define what I call “Grab time”. If you are putting together a joint like a sliding dovetail and others, once the two pieces of wood, with glue, come together, they start to bind. Within a relatively short period of time (much less than the open time) they will bind to the point that you can no longer move the joint further together. I call that the “grab time”. It is essential that the joint be fully seated before you reach the grab time.
Tite Bond 3 is my standard glue. It claims to have a 10 minute open time. I’ve never timed it, but it seems like it’s grab time is about 1 minute.
Sometimes I am doing a rather complex assembly and I have to pull several M&T joints together at the same time. I know I have got to get all the joints fully seated, all the way in, before the end of the grab time. I recently did an assembly step where I needed to bring 4 M&T joints together at the same time. It did not go smoothly and one of the joints ended up about 1/8” shy of being fully seated. IMO, that ruined the piece and wasted quite a bit of QSWO.
I say all this to say that: (1) I wish the glue manufactures would put more emphasis on increasing the grab time as opposed to the open time and (2) I wish there was more information available about grab time of different glues. I have never read anything that tells me about how grab times differ from glue to glue.
If I had the extra time, I would conduct an experiment to measure grab time on different glues. It would be great if some magazine conducted such an experiment and published the results.
Has anyone seen information on, what I call,the grab time of different glues?
-- Rich, Cedar Rapids, IA - I'm a woodworker. I don't create beauty, I reveal it.