Glue Up Clamp Time?

[Bugsysiegals]

"Corner Weld" glue revolutionized the picture framing business back in the 1980s.  It replaced white glue (Elmers) and was much stronger.  It was said to be "optimized for end-grain (miter) glue-ups".

I tested its strength recently against Woodworkers III and found that they were essentially equal in strength (Woodworkers's I, II, or III were not available when CornerWeld came out).

What I did find is that CornerWeld glue would set-up in under a minute.  I would apply the glue to the surfaces of the miters, rub the surfaces together and within 30 seconds they would no longer slip and the grip would start. 

Woodworkers III took about 10 minutes to achieve that same result. 

So if you are looking for a strong bond and very fast setup, then look for some CornerWeld glue.  It is not as easy to find, but it is sold through most picture frame wholesale suppliers.

Amazon shows the product but when you get to the site it is listed as "currently unavailable". 

Lots of listings, but I don't know any of these vendors, so no recommendation.
https://www.google.com/search?client=firefox-b-1-d&q=cornerweld+glue

Thanks for sharing this glue!  It's funny but even with the TB II when I was gluing a drawer it wasn't very long, a few minutes, and I could hardly slide the pieces to align them ... maybe from the glue aging, not sure, but I just need to work faster!

 

[Michael Kellough]

Picture framers have been using “high solids” glue for decades. It’s difficult to get really fine fitting joints with such molding with awkward clamping options from hourly wage workers in an environment where production must continue. The high solids glues like Corner Weld fill the gap.

For fine woodworking where the people you want to impress will be looking at your joints instead of art you need finely fitted joints. Gap filling glue will prevent the joints from closing enough. Expert woodworkers often use Elmers white glue because it’s thin so they don’t have to go counterproductive with heavy clamps. If the joint is well fitted you don’t need much pressure to close it and if the construction is well designed it won’t depend so much on adhesive to maintain it’s form.

I’ve only experienced glue failure when working in freezing temperatures and that was with ordinary commercial wood glue. Maybe resorcinol would have worked. That’s another good option for fine joints.

I’ve used Titebond that has been sitting so long ( more than a decade) that a layer of transparent lower viscosity stuff has separated on top. Stir it up and it will still work.

Back to fine glue joints. Longer term Foggers will remember the main thrust of Rick’s criticism of BowClamps was that not enough pressure could be derived from a pair of clamps four feet apart to produce an invisible glue line. Depends on the stiffness of the cauls and the thickness of the glue and how you define invisible glue line.

I forgot that the op’s question was about how long to clamp.

Depends on how much the joint needs clamps to close. If it doesn’t, and I need the clamps for another assembly asap, as little as 15 minutes at 75* or higher.

A joint that doesn’t need clamping at all, like a glue block behind an apron, just put the block in a generous blob of glue and rub it around to get all the air out and let it be if gravity allows. Add a strap of tape if gravity is a problem. Most people would shoot a nail into the block to “secure it while the glue dries” but that will actually keep the block from settling tight as the glue dries.

 

[Packard]

"Corner Weld" glue revolutionized the picture framing business back in the 1980s.  It replaced white glue (Elmers) and was much stronger.  It was said to be "optimized for end-grain (miter) glue-ups".

I tested its strength recently against Woodworkers III and found that they were essentially equal in strength (Woodworkers's I, II, or III were not available when CornerWeld came out).

What I did find is that CornerWeld glue would set-up in under a minute.  I would apply the glue to the surfaces of the miters, rub the surfaces together and within 30 seconds they would no longer slip and the grip would start. 

Woodworkers III took about 10 minutes to achieve that same result. 

So if you are looking for a strong bond and very fast setup, then look for some CornerWeld glue.  It is not as easy to find, but it is sold through most picture frame wholesale suppliers.

Amazon shows the product but when you get to the site it is listed as "currently unavailable". 

Lots of listings, but I don't know any of these vendors, so no recommendation.
https://www.google.com/search?client=firefox-b-1-d&q=cornerweld+glue

Thanks for sharing this glue!  It's funny but even with the TB II when I was gluing a drawer it wasn't very long, a few minutes, and I could hardly slide the pieces to align them ... maybe from the glue aging, not sure, but I just need to work faster!

TiteBond III has the longest open time of the three options.  I have a PUR urethane glue hot gun.  Strong joints and quick--just like any other hot glue joint.  But it dries black and I rarely use it.  It also has a very short shelf life once the glue is opened.  But nice in that it is wireless.  It retains the heat and you can use this free of any electric cord.
https://www.gluegun.com/products/in...-melt-cartridge-gun-titebond-1361-replacement

 

[Stan Tillinghast]

“ that will actually keep the block from settling tight as the glue dries.”

Whoa—I haven’t heard this before. Do you mean all that pin nailing Norm was doing actually prevented the joints from getting as tight as they should have been?

Say it ain’t so—or for that matter, say it is.

 

[ChuckM]

The results of using brads (in place of clamps) to hold pieces together vary, depending on a number of factors, including the wood (ply vs mdf, for example), brad length, and the joint surfaces. Many had followed Norm's practice of nailing without clamping, and reported good outcomes while some didn't.

As a rule, if I can clamp, I clamp before I nail. I did some moulding pieces once which were difficult to use regular clamps on. After applying glue, I used 3M binding tape to hold them in place and then shot the brads. 

 

[Stone Message]

I'm gluing up some drawer boxes and am wondering how long drawer boxes or cabinet boxes need to be clamped?  I believe I've read clamps aren't needed for very long, not sure if it was 30m, 1h, 2h, etc., and that afterwards you can remove clamps but not to exert any force/stress for at least 24 hours.

That said, how long do you leave your clamps on?  FWIW - I'm using Titebond II.

I use Titebond II most of the time....

Make sure that your workshop is above 12 deg C.

If I am using dominos in the joints I keep the clamps on for about 25 minutes. If the assembly is stable and would not be under any stress after the clamps are removed I would again remove the clamps after about 25 minutes.

If the clamps are required to keep something together that would be under stress for whatever reason (an overhanging section or curved structure) then I would leave the clamps on over night for a minimum of 12 hours.

Titebond II and other PVA glues will start to hold after 15 to 20 minutes. Sometimes with a complicated glue-up more time is needed to get all of the glue spread and the pieces assembled. In this case I use Cascamite which has a long dwell time.

Peter

 

[afish]

Its good to see others echo the whole clamping vs. non clamping.  I think a lot has to do with what you are gluing.  I had told bugs that when I do my domino drawers I often just glue the joint and pop a couple pin nails in the corners to hold it while the glue sets. This is most often with BB so the joints go together tight and flat anyways with very little twisting or warping.  I then just set them aside for half hour to hour and then come back and put in the dominos. If its a large drawer or there is a minor fitmit issue I will use a clamp but that T3 is usually pretty darn good by the time I come back to the first drawer. My climate may help with this too, not sure.  My reasoning is 98% of the drawers joint strength is going to come from the domino and the extra glue used when gluing in the domino.  Any minor strength lost from not clamping the butt joint before cutting in and glueing the domino is essentially insignificant as most of the strength is coming from the domino.  If you are gluing up a table top yes of course you are going to use clamps. However, from what I have been told its possible to over clamp an item and starve the joint of glue. Im sure thats less of an issue when using a domino or M&T type joint.  However, for just a simple butt joint it could become an issue. So im in the you dont have to clamp a glue joint for strength camp as long as the joint fits properly and all things being equal. the clamp is more for alignment and pulling the joint closed if needed. 

 

[Steve1]

A timely thread.

I am currently gluing up plywood workbench drawers with PL Premium.  Joints are done with a lock miter drawer bit.  The PL Premium instructions say 24 hours clamping, but I am cheating a little at 12 hours, simply because I have a lot of drawers to glue up and only 1 set of clamps big enough to do these drawers.    But I am careful not to stress the joint for at least an additional day. 

Time to go downstairs and unclamp the one drawer and clamp up another.

 

[Michael Kellough]

A timely thread.

I am currently gluing up plywood workbench drawers with PL Premium.  Joints are done with a lock miter drawer bit.  The PL Premium instructions say 24 hours clamping, but I am cheating a little at 12 hours, simply because I have a lot of drawers to glue up and only 1 set of clamps big enough to do these drawers.    But I am careful not to stress the joint for at least an additional day. 

Time to go downstairs and unclamp the one drawer and clamp up another.

Why are you using that construction adhesive?
Not saying it won’t work but you’ll really have to use a lot of clamp pressure to get tight joints.
And it takes a long time to cure.

 

[Packard]

A friend asked me to "fix" her kitchen cabinet drawers.  Apparently, they were dealer-assembled using a hot glue gun on the dovetails.

I am sure this was fast and did not require a lot of clamps.  It also did not last very long. 

Luckily the hot glue was reversible with a heat gun.  Woodworkers III worked fine after cleaning up the joints and clamping. 

I have seen hot glue used on the backing board of upper cabinets that had been assembled using dado slots.  I am not opposed to that application.  I think it adds some stability.

 

[Steve1]

Why are you using that construction adhesive?

I find it gives the strongest connection. 

 

[Bugsysiegals]

Thanks for all the feedback ... it's certainly interesting to see the different times, when and when no clamps are used, different glues, etc.

 

[Birdhunter]

Neither my glue nor my wine gets old. But, I do.