A different take on dominoes

[Hornbeam]

One of the problems with pulling up long mitres is getting effective pressure across the joint and stopping everything sliding about. Biscuits or splines can help but may be too big to fit if say wanting to cut a lid off after glue up
Stage 1 take the boards to be mitred about 1mm overlength and cut domino slots in the ends of the boards. Then trim the ends to 45 degrees (so you are cutting off some of the domino slot as well.)
Using 18mm birch ply off cuts I then made some 90 degree dominoes. These ones fit a 5 mm domino amd were rounded with a rasp. I dont suppose you need to be that accurate but you must be accurate on thickness and angle
Glue the dominoes into 1 side only. When dry glue up the mitre and other side of the domino joint. This approach means that when you are glueing up a box you can glue the dominoes in the side panels and then only need to clamp in I direction when gluing the box up with no slip
I know David Barron tried this approach but actually dovetailled the dominoes together. Much quicker and easier to make them out of ply

 

[Sideways]

This would be a good application for ready made mitred dominoes moulded in one piece from plastic.
I wonder how strong a 3d printed version could be made with the right choice of filament ?

 

[TRITON]

Certainly has an application on thinner pieces.


Interesting...

 

[Just4Fun]

I wonder how strong a 3d printed version could be made with the right choice of filament ?

Is strength important or is this intended to be an alignment aid?

 

[AndrewG]

Fine Woodworking covered this approach a while ago. As well as plywood and finger jointed L tenon's, the idea that stuck with me (but not yet tried) was Tim Coleman's. He used aluminum L extrusion, padded with wood shims to the correct thickness. If you go to his website you can find the article

https://timothycoleman.com/wp-content/uploads/2017/06/Add-Muscle-To-Your-Miters-Final-compressed.pdf

 

[Hornbeam]

The pieces joined were 13mm, The joint gives strength and alignment I am sure with a bit of thought the domino could be machined in batches. The advantages of ply is that you effecticvly have a strong finger joint at the corner

 

[Sideways]

Fine Woodworking covered this approach a while ago. As well as plywood and finger jointed L tenon's, the idea that stuck with me (but not yet tried) was Tim Coleman's. He used aluminum L extrusion, padded with wood shims to the correct thickness. If you go to his website you can find the article

https://timothycoleman.com/wp-content/uploads/2017/06/Add-Muscle-To-Your-Miters-Final-compressed.pdf

Those would be great for strength.
Improve and simplify a step further, just cut the L tenons from sensibly thick aluminium (4, 5, 6mm say, whatever matches your domino cutter) and no need to mess about with wood shims.

You can buy aluminium angle in all sorts of dimensions and thicknesses, including unequal length sides.

 

[Spectric]

The alloy L sections that @Sideways suggest would be much stronger than the glued ply, with the ply you are introducing another joint on the same plane as the actual corner joint but then do you only glue the wood and leave the alloy floating .

 

[bilboburgler]

dominos were invented for alignment in factory made environments, fast and efficient. Then they moved into the domestic market and at the same time suppliers took the opportunity to do a rasor blade marketing BS thing on them so you have to buy the propriatery product. Then they dropped the cost of manufacture but kept the price up (don't you just love marketing) making absorbant badly shaped things that don't align and don't strengthen.

But they are quick and easy. If you must use these things I would 1) make sure the biscuit is made of good quality wood rather than absorbant cardboard and that it fits the slot you made with the baby router thing that makes biscuit slots, 2) if dowels are easier for you (eg you have a drill, {drills are so cheap and so easy to use}) use them and an alignment jig, 3) just cut a slot with a normal router and stick a piece of wood in the slot. Each of these offer the benefits of alignment with more and more strength and none of the costs of a biscuit tool thing.

 

[paulrbarnard]

dominos were invented for alignment in factory made environments, fast and efficient. Then they moved into the domestic market and at the same time suppliers took the opportunity to do a rasor blade marketing BS thing on them so you have to buy the propriatery product. Then they dropped the cost of manufacture but kept the price up (don't you just love marketing) making absorbant badly shaped things that don't align and don't strengthen.

But they are quick and easy. If you must use these things I would 1) make sure the biscuit is made of good quality wood rather than absorbant cardboard and that it fits the slot you made with the baby router thing that makes biscuit slots, 2) if dowels are easier for you (eg you have a drill, {drills are so cheap and so easy to use}) use them and an alignment jig, 3) just cut a slot with a normal router and stick a piece of wood in the slot. Each of these offer the benefits of alignment with more and more strength and none of the costs of a biscuit tool thing.

Not a fan of dominoes then?

 

[Stuart Moffat]

Conflating dominos with biscuits doesn’t suggest practical experience of both/either?

 

[bilboburgler]

But thinking they are different is equally interesting as really one is just an attempt to get around the patent control of the other. Both can be enhanced by making sure you follow the ideas noted above and can be done better and more cheaply using lower cost tools and probably just as fast. However the key benefit of using them is you can use cheap unskilled labour as they almost ***** proof the process. Hence they have their place in the workshop especially if you have to bring in lesser skilled people to help you or frankly if you have a cold shed you just want to get out of asap.

My father introduced them to his workshop many years back when he needed to expand production and they offered a route to low skilled labour. Once that work died off he packed them away as they only almost ***** proofed the process and the waste cost didn't make sense.

My own interest in them is minor but they are used by part of our workshop which a Mens Shed uses and they want to build bird boxes. Which perfectly fit the whole unskilled labour and the birds don't mind if the box is slightly off. For furniture, there are better, simpler routes forward.

 

[Sideways]

But thinking they are different is equally interesting as really one is just an attempt to get around the patent control of the other.

I really don't agree with this.
Even someone like me who has never used a domino can see that you can build gates and doors using large dominos that you wouldn't ever try to build with biscuits.

Applications of the domino appear to have more overlap with dowels than with biscuits.

 

[Hornbeam]

But thinking they are different is equally interesting

I think you havetotally missed the point both of my original post and the pros and cons of biscuit jointers and dominoes
I have used lose splines and loose tennons long before either toot was common place, A loose tennon is a standard approach to repairing broken tennons in old furniture.
I do think that as the biscuit jointer cane first biscuits were often used in a lot of places where they were not really suitable.
Biscuits are excellent for alignment and provide significant strength in long edge joints and can be used for end grain to side grain where there is a reasonable length and the stresses arent high. (I would not use them for say a rear chair leg joint) Good quality dominos are made of compressed beech laminate
The domino is almost a game changer and is a high quality very strong loose tennon. The Donino is solid compressed beech but I have also made my own from other hardwoods. A domino is perfectly strong enough to replace a traditional M&T joint . Thet are engineered to very tight tolerances and give excellent alignment (personally I never use the sloppy fit settings) A tight domini is way stronger than a sloppy M&T
Sometimes I do hand made M&T joints but it isnt for strength, Speed is a huge issue for commercial makers. The other aspect of tight small neat joints is that you havent removed 3/4 of the material from the post leaving it weak and prone to future failure
The principle point of this post was to give a method which gave excellent alignment during glue up and gave considerable strength to the completed joint. @bilboburgler can you provide an alternative approach which leave the grain free to run round the corner

 

[Ollie78]

This is a good method and reminds me of an idea that I keep coming back to.
I have seen the bed assembly dominos they make or connection system as they call it because they sent me a couple to try.
I could not help thinking that they could make a hinge in the same way, like a Soss or Tectus concealed hinge that just fits in a domino slot like the connection system does. It would be the single fastest hinge to fit ever.

Ollie