Domino glue up problem

[Crazyraceguy]

I believe that about you [member=57948]ChuckS[/member] that is for the benefit of those who come along later.

 

[ChuckM]

I believe that about you [member=57948]ChuckS[/member] that is for the benefit of those who come along later.

[big grin]

 

[Jim_in_PA]

I will add to this conversation (and it may have already been mentioned, but I read quickly) that one should also choose which Dominos actually need glue. I don't, for example, use glue on the Dominos for a large panel glue up (such as a table top) as they are employed primarily for alignment of the top surface of the panel to reduce the amount of work necessary to level it later. I do use glue if a Domino is participating in joinery on smaller parts as they are then being used as tenons in mortises for strength, often in cross grain situations. You don't need a "yuge" amount of glue for this as has been noted.

 

[Crazyraceguy]

I will add to this conversation (and it may have already been mentioned, but I read quickly) that one should also choose which Dominos actually need glue. I don't, for example, use glue on the Dominos for a large panel glue up (such as a table top) as they are employed primarily for alignment of the top surface of the panel to reduce the amount of work necessary to level it later. I do use glue if a Domino is participating in joinery on smaller parts as they are then being used as tenons in mortises for strength, often in cross grain situations. You don't need a "yuge" amount of glue for this as has been noted.

It has, but it's worth repeating, especially in isolation from other comments

 

[jshippy90@gmail.com]

Hi just wanted to mention if your boards are flat and straight dominos are waste of time on a panel glue up

 

[ChuckM]

Even when the boards are flat and straight, they can slide as you clamp them, and often we use clamping cauls or blocks (below) in a panel glue-up. Dominoes may still be useful or helpful in some of the panel glue-ups.

[attachimg=1]

 

[Crazyraceguy]

Hi just wanted to mention if your boards are flat and straight dominos are waste of time on a panel glue up

That sounds good in theory, but "glubrication" adds complexity.

Many things that go perfectly as a dry-fit aren't as simple once the glue gets in there. Gluing more than one seam at a time exacerbates this issue.

 

[Jim_in_PA]

Yea, I agree with Chuck...a few Dominos keep "the slide" more at bay when gluing up a panel so for me, they are not a waste of time at all.

 

[TheLastTool]

In looking at the picture I see a rabbit on the bottom edge of one of the pieces. I am wondering if this is causing the joint to bow upward and open.  Are the dominoes install during the dry fit up? If so and the dry fit up is ok then the problem is in the clamping or as others have said to much glue.

Agreed, at least partly. The contact with the long edge of the rabbet would create a bow downward, but that should be negated by the clamp bars. Ultimately though, there was no mention of a bow, just not closing.
Tite-bond 3 is a fairly slow setting glue, as far as typical wood glues go, but it will still cause swelling/tightening of the tenons.
Nine Dominos may be too many, especially if your boards were nice and straight, in the first place. This increases the difficulty of pressing this all together.
As an aside,
unless there is some specific reason that you can't do it later, I wouldn't cut the rabbet first. You risk denting the edge because of the lack of surface area on that edge.
Also, your clamping pressure would be far more even if you clamp from both sides. All of yours are on the bottom, a few from the top, could straighten things enough to close up better.

This was all 2 months ago. Did you finish this project? Better results?

I think it worked out ok 

 

[Mini Me]

What Chuck said, sometimes when I’m using dominos in this application, I dont even glue the dominos in. They are there for alignment only.

I have never understood why gluing Dominos is either needed or desirable. Perhaps it is because I see them as an alignment tool and not adding strength to the job.

 

[smorgasbord]

That sounds good in theory, but "glubrication" adds complexity.

Many things that go perfectly as a dry-fit aren't as simple once the glue gets in there. Gluing more than one seam at a time exacerbates this issue.

If a dry-fit fits perfectly, then one would assume that with the only difference being the presence of glue, that glue is the issue.

For this kind of edge grain gluing, you don't need strength from the dominos. Hence 12mm is way too thick. Back in the day I built my workbench top from maple boards turned sideways to get an over 3" thickness, and used biscuits for alignment. Would probably still use biscuits today, even though I own a DF700. I save the domino for when the biscuits are too wide or I actually need the strength from a glued loose tenon.

 

[luvmytoolz]

What Chuck said, sometimes when I’m using dominos in this application, I don’t even glue the dominos in. They are there for alignment only.

I have never understood why gluing Dominos is either needed or desirable. Perhaps it is because I see them as an alignment tool and not adding strength to the job.

I assume anything I make will be used, misused, and abused galore, so I glue everything in sight when I assemble anything! Nothing I built ever came apart by accident! ;-)

 

[Jim_in_PA]

I have never understood why gluing Dominos is either needed or desirable. Perhaps it is because I see them as an alignment tool and not adding strength to the job.

I agree relative to panel assembly since they primarily provide alignment rather than any structural benefit. But for Dominos used for loose tenon joinery, gluing is meaningful to structural strength. I actually follow these practices in my own shop and it's worked out well.

 

[waho6o9]

"so I glue everything in sight"
This ^ is the way.......
View attachment 1

 

[ChuckM]

[scared]

Waho6o9 -

Glue fall?

[tongue]

I use only a decent amount of glue with minimal glue sequeeze-outs (no glue squeeze out isn't necessarily a good practice though). I apply glue to both the dominoes and mortises on all joints, including panels.

 

[Cheese]

I also glue everything in sight... [big grin]...what really helped me with glue-ups is when I started to use flux brushes to apply the glue. The flux brush lays down a nice consistent layer of glue and it applies that evenly over the entire surface. No more massive amounts of glue squeeze-out or hydraulic lock to contend with.

Like Birdhunter, I also only glue up one joint at a time. That gives me time to wipe off any extra glue around the Domino tenon body and the edge of the board with a damp rag.

Here's a joint I constructed from fir 8 years ago that I intended to break apart to monitor how evenly/unevenly the glue was applied with a flux brush and to see what parts adhered to each other and how strong the adherence was.

Photo 1: Interesting to note that despite the end grain/long grain bond, the end grain still retained/removed quite a bit of the long grain from the other board...it's only the very small areas with the red arrows where there was no end grain adhesion.
The yellow arrows highlight how uniform the glue coverage is when using a flux brush...no hydraulic lock here.  [smile]

Photo 2: Look at the long grain of the Domino and notice it's removed wood fibers from inside the mortise. If you need or want some extra strength within the joint, don't be afraid to glue the Domino, it can be used for more than just aligning boards together.

Photo 3: Notice all of the long grain fibers that were ripped out and are permanently attached to the end grain. Also note that to break this joint apart, I had to break the mortises open because of the long grain-to-long grain bond between the Domino and the mortise.

[attachimg=1]

[attachimg=2]

[attachimg=3]

 

[luvmytoolz]

Another thing I always do is apply glue to all surfaces being joined, not just one side as I see so often, especially with makers producing chopping boards.

I don't know if that's overkill, but I have taken apart quite a lot of doors and furniture made by others to reclaim the timber, and many come apart surprisingly easy.

One piece in particular was butt joined and the dominos were almost bone dry, I think the glue had set before inserting, and probably not enough applied as well.

I sue the silicone brushes myself now, and for laminating I use a small 3" feed roller off Ebay that does a fantastic job of a nice even coating, not too thick. Saves me a massive amount of time.

 

[bobtskutter]

I read somewhere, might have been on the FOG, that applying PVA type glue to both surfaces makes sure both surfaces are "wet".  Apparently you can end up with the glue being sucked into the pores of the wood and get a dry joint.  For panel glue ups (and I've not done that many) I apply glue everywhere!  Both surfaces and into the domino mortise.  I use a small plastic spreader to distribute the glue in the mortise slot.

Bob

 

[jeffinsgf]

Here's a joint I constructed from fir 8 years ago that I intended to break apart to monitor how evenly/unevenly the glue was applied with a flux brush and to see what parts adhered to each other and how strong the adherence was.

Cheese, your research project is pretty fascinating.

How long did you let the joint set before you broke it apart? The bond between the end grain and face grain is what makes me ask. It's what I would expect to see on a relatively new assembly. As I understand it, failures between end-grain and long-grain joints happen after the joint goes through a couple seasonal cycles. The long-grain moves and the end-grain doesn't and the bond breaks down.

The stock adhered to the Domino and ripped out of the mortise is reassuring. Gives me confidence in all the stuff I've built with Dominos.

 

[waho6o9]

Sizing, applying glue to end grain to be absorbed first and letting dry, and then doing your glue up isn't done much
these days because of time constraints.