# Miter waterfall bench joint



## Newbeewood (Jul 25, 2018)

Hello, new poster long time veiwer. I have some questions about the strength of this jointer in reference to how many people can it support. I make them appx 60"long by 16"wide by 18"tall out of 1.75" thick alder. I use 7 10/50 dominos. Anyone have personal experience with these? I would appreciate the input.

Thx
James 
"What's your next build made of"


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## jonah (May 15, 2009)

With dominos or splines it's plenty strong.

When you say "how many people it can support," i presume you are talking about making a bench with that design.

So long as you provide some lateral stability via the dominos, you'll be fine.


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## Unknowncraftsman (Jun 23, 2013)

James just test the joint.See what it takes to break one.
Don't you think this is better then the opinion of a bunch of strangers that probably have never built one.
I sense your concern because it a very small connection. And you never know how much weight you need to support since people come in all sizes.
The benches I make are over built for this reason.








Good luck


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## Newbeewood (Jul 25, 2018)

Thx for your responses. Jonah, the more I read about the strength of domino the more I find that they might not be as strong as I think. According to some stuff I see it is only of the weaker ones. They test just one doomino and I am using 7 so I would expect it to hold but all this reading has got me wondering.

A.J. you are exactly right and that is what I am doing now. Nothin better than real testing in-house.

I had another idea last night, could I make that same miter joint and using dominos on the outside to align during glue up, then than mortise out a 10"x1/2" section on each face of the miter. Glue up the joint like normal with nothing in the mortise. Than after glue has cured drill a little hole in the seam of the inside miter and than fill the mortise with epoxy using a syringe and a needle. this maybe totally crazy but would this work? Would this make the joint really strong? Is anyone interested in seeing this tested?

Thanks again for input.


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## jonah (May 15, 2009)

That wouldn't appreciably increase the strength, I don't think.

A fairly beefy wood spline would, however.

You could also add a diagonal brace, though it might compromise the look you're going for.


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## LesB (Dec 21, 2008)

If the only connection for the sides and top is the mitered joint I think you will have problems with lateral strength. I would want some sort of "stretcher between the ends and as indicated a diagonal type brace would be best. Another alternative is an apron but that might not fit the design.


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## AandCstyle (Mar 21, 2012)

James, I used splines on one I made and it has been fine, but my son doesn't often have people standing on his furniture.  I also used epoxy to glue the miter. You could route out a mortise for a piece of angle aluminum and screw that to the two pieces and glue it all up with epoxy. FWIW


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## Newbeewood (Jul 25, 2018)

Thanks Art. I am going to try something similar and test it's strength. I will post
My results here for anyone interested. 
The first photo is using smaller dominos









This photo is my experiment which I am going to fill the mortise with epoxy after glue up.


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## Newbeewood (Jul 25, 2018)

As for using a brace that takes away from the look that I want.


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## enazle (May 18, 2018)

I once built several tables using a butterfly dovetail spline. It would be perfect for your application. You have to use a back-up when cutting the joint through the opposite end or it will blow out.


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## Newbeewood (Jul 25, 2018)

Update. So I test my joints and I had a hard time setting up a system to try to break the joints and measure the load. So I decided to just jack up my truck and let it rest on the joint and see how long it took to break. I tested two different kinds one with two dominoes at each corner glued together with a mortise in the middle filled with epoxy. It only took 2 1/2 minutes for it to break with the epoxy. The other one was three rows of dominoes about 2 inches apart totaling 18 dominoes 12 of them were 85 The other one was three rows of dominoes about 2 inches apart totaling 18 dominoes 12 of them were 8/40 and 4 where 5/30. It took over 45 minutes for the joint to start to break apart and would never completely come apart


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## PCDub (Sep 24, 2017)

Wow! Impressive test! Thanks for posting your results!


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## Newbeewood (Jul 25, 2018)

Yeah I was surprised. More dominos like finger joints as some people suggested make a very strong joint. This is how I will do my miter joints from now on. If it can hold a truck I think it should hold but to people.


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