Glue Knowledge

[Jack]

As woodworkers, we all have plenty of experience with glue. Here is a video I stumbled over that is somewhat entertaining, and gives you something to do while the Government has you bent over clenching your buttocks and wringing your hands over the cold virus.

My personal experience with glue is long and extensive, and I can say with confidence that my experiences have (almost) always exceeded my expectations.

This video has one overwhelming flaw which I'll keep to myself, wondering who else will notice, or rather who won't notice...

[bnwelch]

I didn't watch to the finale, but it appears the center of gravity of the load was not consistent. Particularly evident during the epoxy/miter test...

[Mark H]

The plywood is coming apart. The glue is good

[Jack]

On that test, she had I believe 75 lbs on the joint, but the text in the video said 409 lbs. She was saying the weight correctly, but the text was grossly off by a lot. The tests were interesting anyway,and while not scientifically accurate, close enough for government work...

[Jack]

This was accounted for in the video, and all glues didn't past muster. She also tested solid wood. I was surprised by the mitered joints and how they held up, particularly with epoxy.

Also surprised by how pre-gluing or sizing the edge grain miter joints didn't help at all. I had read sizing mitered picture frames would greatly strengthen the joints, and was planning on doing that the next time I make picture frames even though I have a 100% success rate w/o doing that. Typically, I just glue them and clamp them with my pin nailer.

[Clare Snyder]

I think the text was the calculated load on the joint itself - taking into account the mechanicaladvantage of the moment arm - - -

[Clare Snyder]

The diluted glue used for "priming" the joint left a low strength "boundary" layer separating the full strength glue from the wood fibers. PERHAPS letting the prime coat cure before applying the full strength glue and assemblingthe joint MAY have improved the results

[Jack]

I think you may be right on that.

[Clare Snyder]

Back in the hot hide glue days priming was VERY common. You filled the end grain, in particular, with glue and let it set - on both surfaces

- then added a "filling" to the sandwich and assembled the joint.

[Leon]

Typically glues does not adhere well to cured glue.

[Mark H]