do box joints for drawers need clamps when gluing - why? because glue open time

[Cory filder]

newb question.
Just as it says in the title. I recently saw Mattias Wandel's channel last week make a drawer with the box joint and no clamps. I have never made a box joint project before. the amount of open time has me a bit concerned. Provided i get the angle correct, do I really need to clamp box joints? if so, do band clamps provided they have good corner support work if clamps are required? band clans would have me a bit concerned about getting 4 right angles.

let me know what's possible
thanks

[jack duren]

If they go together smoothly, if not a little persuasion doesn’t hurt..

[Jamie Buxton]

You should clamp the width of the drawer and the front-back direction. That will prevent the parts from sliding apart. Use as many clamps as you find necessary to close the joints tightly. Sometimes the parts are twisted or curved, and need more than the minimum number.

When I'm gluing up drawers, I use shop-made corner braces. They are L-shaped, just cut out of scrap plywood. I clamp them inside a drawer corner to assure it is 90 degrees. Usually I use two per drawer. You can buy the same thing made out of plastic from Rockler or Woodcraft.

[Lee Schierer]

When I make drawers or boxes with machined dovetails or box joints, I use clamps to hold the joints tight in both directions. I also check that the boxes/drawers are square before the glue sets up. If your sides aren't perfectly flat the clamps will insure any minor cupping is pressed out.

[Stan Calow]

Rockler has these cauls for clamping box joints: https://www.rockler.com/box-joint-cauls-box-joint-jig-cauls-sold-separately?country=US&sid=V91040&promo=shopping&utm_source=google&utm_medium=cpc&utm_term=&utm_content=pla&utm_campaign=PL&gad_source=1&gclid=CjwKCAiAt5euBhB9EiwAdkXWO30c9em2s2huJtgMSEXP jvPQahWxVukGf9JzxB3LiX2broMGYjwd_BoCXwIQAvD_BwE

[Paul F Franklin]

I have those cauls and they work pretty well as long as your joints are exactly 1/4 or 3/8. If they are just a hair over or under the cumulative error over a few inches prevents the cauls from lining up and pressing on the fingers properly over the whole length of the joint. I wish they had made the fingers on the cauls a little narrower to provide more margin for error.

[Paul F Franklin]

Titebond extend glue buys you a little extra time for the glueup, and keep in mind that you don't have to get perfect glue coverage; there are so many redundant glue surfaces that you don't need to strive for perfect coverage. And don't bother trying to get glue on the end grain parts of the joints; just swipe a dab on each side of each finger.

This is what I like to use to apply glue quickly to finger joints; dip the corner into a little puddle of glue and swipe it on the side of the finger. Then flip the spreader and do another.

515312

[Richard Coers]

When you slide the joint together, a layer of glue builds up in the bottom of the joint. If you don't clamp it, it won't go wood to wood in the joint. Don't fit the joint tight when you test fit it. The glue swells the wood and it basically locks up before the wood is seated.

[Warren Lake]

many production drawers were dovetail. They had a glue pot with a whole line of male dovetails from aluminum all in a row on a hinged thing. That dipped in one shot and then it put glue into all the female dovetail cut outs at once. Forgot who made the machine

[jack duren]

I’m surprised at the need for clamping box joints. I rarely clamp and on dovetails if it doesn’t fit snug and hold itself together I have a failed joint on dovetail or box joint..The glue is the lube to slide them together..

As mentioned … titebond extend is a great glue if you need a lot of time.

[Cory filder]

When you slide the joint together, a layer of glue builds up in the bottom of the joint. If you don't clamp it, it won't go wood to wood in the joint. Don't fit the joint tight when you test fit it. The glue swells the wood and it basically locks up before the wood is seated.

I had not considered the swelling. How loose should it be?


I’m surprised at the need for clamping box joints. I rarely clamp and on dovetails if it doesn’t fit snug and hold itself together I have a failed joint on dovetail or box joint..The glue is the lube to slide them together..

As mentioned … titebond extend is a great glue if you need a lot of time.

and you had no negative consequences for not clamping?
I will definitely be buying tight bond extend.

in Matias's video, he did it in steps. (1 or 2 joints per glue up rather than all 4). the one thing I like about that is at the open time is far more extended then just using longer open time glue alone. this is the main reason why my ears perked up. I have a very good square, and I figure if I get it perfect, I would also have to rush less, which means less errors.The final glue up would be 2 joints rather than 4
do you think of this?

[jack duren]

If you have set your jigs, if that’s what your using are set up correctly, it shouldn’t require a lot of force to press them together. Joinery are the three bears. Too loose, too tight or just right. That’s my theory for woodworking

Not sure if the big boxes carry it on the shelf? Maybe someone knows?

[Paul F Franklin]

I had not considered the swelling. How loose should it be?



and you had no negative consequences for not clamping?
I will definitely be buying tight bond extend.

in Matias's video, he did it in steps. (1 or 2 joints per glue up rather than all 4). the one thing I like about that is at the open time is far more extended then just using longer open time glue alone. this is the main reason why my ears perked up. I have a very good square, and I figure if I get it perfect, I would also have to rush less, which means less errors.The final glue up would be 2 joints rather than 4
do you think of this?

You can slip the 4th side in with no glue while gluing the other two joints just to make sure everything is lined up. Of course you'll still want to make sure everything is square. When the first glue is dry, slide out the 4th side and glue it up to finish. That does take some of the time pressure off. Once you do a few you may find you are fast enough that you can do them all at once, but it's a good way to to make the first few easier.

[Thomas McCurnin]

I clamp them to insure a 100% square joint. I use blocks of wood on the outside face of the box/drawer, just a little inside the box joints and use light clamping pressure to squeeze the two sides together. Repeat on the opposite face. Usually I have a drawer or box bottom which interferes with assembly, so clamps are a good way to insure a nice tight box.

[Richard Coers]

I had not considered the swelling. How loose should it be?



and you had no negative consequences for not clamping?
I will definitely be buying tight bond extend.

in Matias's video, he did it in steps. (1 or 2 joints per glue up rather than all 4). the one thing I like about that is at the open time is far more extended then just using longer open time glue alone. this is the main reason why my ears perked up. I have a very good square, and I figure if I get it perfect, I would also have to rush less, which means less errors.The final glue up would be 2 joints rather than 4
do you think of this?
The joint should slide together with no resistance. If you have to tap it together with a mallet, it's too tight. I suggest you make a couple of samples and test the theories presented. I have never glued up a drawer without clamping in 55 years. The dimension always changes a bit when you push out the heavy glue line at the bottom of the joints. Maybe folks are using a hammer to move that heavy glue line, but I like to use a clamp. It's just a small move, but since it's two glue ups for the width of the drawer, it could add up to a 1/64". I definitely don't buy slower glue either. But what do I know?

[Derek Cohen]

No mention has been made so far of an important reason to use clamps ...

The obvious reason for clamps is to ensure a solid and square fit. But one must recognise that solid wood will move. I often glue up dovetailed boards, and they have developed a slight cup between the time they were made and ready for glueing. Clamps ensure that they are seated fully until the glue dries.

Regards from Perth

Derek

[glenn bradley]

Many PVA glue makers recommend clamping pressure as part of how to use the glue. Resins and other formulations will vary. I tend to follow manufacturer's recommendations so I clamp things even when they fit really well if I am using a PVA glue. Why not? I have the clamps and applying them when things fit well is the easiest clamping job ever ;-)

[Jimmy Harris]

If the joint is tight enough to hold itself together, then you don't need clamps. I never clamp dovetail joints for this reason. But for a box joint, the pieces aren't locked together through geometry, but rather through friction. And wood glue reduces friction. So you're more likely to benefit from clamps. But if it holds tight on its own, then you don't need clamps. The strength comes from the long grain to long grain glue surfaces, and your clamp is likely to put pressure against the end grain to long grain part of the joint, which isn't where you're really looking for strength. So clamps don't add to the joint's durability, but they do add to the joint's precision.

In other words, it's not required, but it doesn't hurt (if done right) and can, in some cases, help. You can tell if clamps are needed when you put it together. If you can easily move the joint with your hands, then clamps are a good idea. If you have to bang it with a mallet to get it aligned, then clamps aren't necessary.

[Jim Becker]

I would clamp...but not "over clamp" and not right on the fingers. I'd use the clamps to keep things where they need to be while the glue is still slick for the reason that Jimmy just mentioned. Stabilization, in other words. The assemblies don't need to stay in clamps for a long time, either. An hour is generally more than enough for PVA glues; some other types of glue may require a longer period because they have a long working time.

[jack duren]

There’s no A, B or C to this question. If you need them , use them. If not , don’t..

[Edward Weber]

I agree with Derek and Glenn.
There are reasons to clamp but whether you use them or not is up to you.

I would also say, don't look to MW for fine woodworking methodology, JMHO