Gluing up at 8% humidity

Carol Reed

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Coolidge, AZ
...is a RACE. Whew! I had EVERYthing ready. Total dry clamp up. Everything laid out like a surgeon. It still was a bear. It was only 6 pieces. Next time 2 pieces at a time.

So far so good. I looked very carefully to make sure everything was properly placed, but that is just more pressure than I want to work under.

The trials of DRY heat! :rofl:

BTW, I used one of the new Rockler glue brushes. Really like it. Good thing the glue peals off. At this rate it dried pretty fast!
 
:) I think my shop would be an oven right now too, was 106 in there Saturday with all the doors and windows open. Luckily I was only out there to load up the PB and had the AC going in the office.
 
Temp was only 85º. Reason for working out there between 5AM & 9AM. But the humidity is in the single digits. Hottest part of the day it's 120+º in there. Not me!
 
During the fall and winter my basement shop is below 5% and temps in the basement around 60 degrees. I have to do large glue ups in small sections because the glue tacks so fast.
 
According to the Titebond people, the open time between I & II is the same. See here:

http://www.newwoodworker.com/reviews/titebond.html

This stuff skimmed over moving from the brush to the assembly! About 4 seconds. Sheesh! Wood was really, really dry also. I was gluing ledgers on the edges of 3/4 BB ply. Glued both surfaces. Mated them and could hardly get the clamps on them to close the gap evenly. I could move the ledgers maybe a 1/4" to even the edges within 2 seconds. Have never seen this before and I have lived in the Southwest since 1964.
 
Carol,

When I have larger glue-ups (currently I am combining cherry boards to make 6 foot long solid panels), I mist the edges with water, then wipe any excess off, and go (using Titebond I). This adds enough moisture to the area of the joint that the wood doesn't "suck the moisture" out of the glue. It increases the open time significantly, and I have not seen any negative effect in the strength of the joint.

Note that I am just misting the surface with a spray bottle, and then wiping with a dry rag, so there is virtually no water on the surface, and the glue is not noticeably thinned.

My problem is not the atmosphere humidity, but an improvement in how the wood takes the water out of the glue may help compensate for the low relative humidity in the air.
 
Thanks, Charlie, that was really helpful and it makes a lot of sense. I will try that this coming week as there are more glue ups coming.
 
If there is any question at all about whether I have enough open time on glue, I use Titebond Hide Glue. 10 or more minutes to move a joint or adjust for square is absolute heaven.
 
If there is any question at all about whether I have enough open time on glue, I use Titebond Hide Glue. 10 or more minutes to move a joint or adjust for square is absolute heaven.

The down side to premixed hide glue is that it takes a long time to build strength. With Titebond I I can remove clamps in an hour or two, even through full strength is not achieved for a day or more. I have had Titebond hide glue joints come apart when clamped for a few hours, although the joint seems fine if it stays clamped overnight or longer. I don't believe "real" hide glue has the problem of needing long clamp times, but I don't use it.

For veneer, bent wood laminations, and other projects that need long open time, I use plastic resin glue - the kind you mix the powder with water.
 
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I have had Titebond hide glue joints come apart when clamped for a few hours, although the joint seems fine if it stays clamped overnight or longer. I don't believe "real" hide glue has the problem of needing long clamp times, but I don't use it.

What you say about longer clamping times is true, but I'm not pressed for time and always schedule glue-ups so I don't need the part until the next day. I've never had a joint come apart. The extra time is easily compensated for by the extreme ease of cleaning up any squeeze-out.
 
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