Can a Glued Joint Dry Too Fast?

gpwestmoreland | Posted in Joinery on September 19, 2001 01:41am

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Your opinions wanted , please. Usually, after gluing up a panel (or other small to medium sized project), I set the clamped up item against a wall in a corner of the shop to dry, and to free up the workbench for other work. Sometimes I set it outside in the shade, leaning against the shop wall, where the temperature is usually about 20 degrees warmer than inside. Of course, the glue sets up much faster in the warmer temperature. Can this be overdone? The daytime temp. here in the desert in August generally runs 105 to 110 degrees. Can you diminish the quality of glue joints by drying them too fast? My inquiring mind and impatient nature would like to know. Thanks for your thoughts on this. GP

Replies

Danford_C._Jennings | Aug 27, 2001 07:50am | #1
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GP,

While I am not a chemist, I can read labels. The glues that I use have temperature ranges and I have found that yes, some can dry too fast especially on your denser hardwoods such as Maple and Birch. My take is that the glue needs to penetrate the fibers to get a good bond. I'll leave it to the chemists to verify.

FWIW, I live in the high desert of Southern Oregon (Klamath Falls) and we do not see such high temps. I try to schedule glue up and finish operations in the mornings before the shop gets up to 85 or 90, hit the links or stream, then continue in the cooler evening hours. FWIW.

Dano

CStanford_ | Aug 27, 2001 12:53pm | #2
*Yes, you can GP. That temp is too hot. Take them in the house.

Howard_Acheson | Aug 28, 2001 03:08pm | #3
*My rule of thumb is no gluing or finishing unless the temp is between 55-80 degrees. As far as humidity is concerned, no finishing unless the RH is between 25-75%.When I was involved with a custom cabinet/furniture shop, I had many discussions with adhesive and finish manufacturers and most problems resulted from environmental issues.

redplumjam | Aug 30, 2001 02:39pm | #4
*i am in the wrong part of the country.alex

Rickk_ | Sep 03, 2001 01:25pm | #5
*I prefer to go by scientific evidence over opinions.http://www.fpl.fs.fed.us/documnts/FPLGTR/fplgtr113/fplgtr113.htmRead the Forest Products Handbook. Nice chart on 9-13 and other mentions of heat and glue in the chapter. Depending on the glue you can even go hotter. We use a German press to put on 3/4 bandings and a platen heats the solid wood banding up to 200 degrees and with 3 minute press time we can machine the wood immediately. Also radio Frequency gluing has been used for years which essentially gives instant curing by getting the molecules moving (heat)
CStanford_ | Sep 19, 2001 01:38pm | #6
*I would not necessarily equate high-speed factory style gluing with a quality joint. Gluing banding is less mission critical than gluing the panels themselves. Factories make trade-offs determined by the cost accounting department. The problem with 'setting something in the sun' to dry is that one loses control over the process. RF gluing in a controlled environment is probably better than setting a panel in the sunlight, but neither one are probably better than letting the panel rest in the shop in which the stock has become acclimated until the glue has fully cured.