# Festool's dominoes.....just fancy dowels



## DouginVa (Mar 5, 2012)

An old friend just commissioned me to build him a stereo cabinet/shelving unit and he wanted to re-use the legs from a previous shelf unit that he had made (by somebody else). The 2" thick shelves were joined to the legs by Festool's dominoes. I had to separate the legs from the shelves in order to re-use the legs. So I broke out the dead blow mallet and much to my surprise the legs came off very easy.

It reminded me of dowel joints that I used to use many many years ago when I first got in to woodworking. Back then I found they made horrible joints and they separated very easy. It's like the glue only served as a lubricant to get the dominoes into the mortises.

Don't mean to rain on anybody's parade who had spent a ton of $$$ on that tool, but….....Anybody else notice this about those dominoes?


----------



## vipond33 (Jul 25, 2011)

Dominoes are just like dowels; fully coat the holes, fully butter the snug fitting clean insert pieces and you ain't never going to knock it apart. Never.
Put a drop of glue in the hole, insert the domino and yeah, sure, it'll fall apart. But so would an exactingly made mortise and tenon joint.
gene


----------



## iminmyshop (Dec 9, 2012)

Put a drop of glue in the hole, insert the domino and yeah, sure, it'll fall apart. But so would an exactingly made mortise and tenon joint."

Yup.


----------



## ShaneA (Apr 15, 2011)

Never used one, but if properly glued…it would yield an incredibly strong joint. They look to be a very handy tool. Maybe these joints were glue starved?


----------



## oldnovice (Mar 7, 2009)

I made a table in 1976, before biscuits and dominos, and I made my own biscuits/dominos out of 1/4" plywood. I used 8 of these to join the four sides of my table top by routing mortises in the 1" thick red oak pieces. I used plywood as I thought plywood would be stronger than solid wood.

These joints are still fine, in fact I am writing this on that table.


----------



## RockyTopScott (Nov 16, 2008)

A properly sized and glued domino is not coming apart


----------



## a1Jim (Aug 9, 2008)

I've never had a mortise and tenon joint "fall apart" ,if hammered the wood around the tenon breaks first,if glued properly. Since I've never used a Domino I can't say how they work, but they appear to be over sized dowels or undersized loose tenons. From their appearance and size I would much prefer a larger loose tenon.


----------



## runswithscissors (Nov 8, 2012)

So when is Harbor Freight going to come out with their clone of the Domino?


----------



## mcase (Oct 31, 2009)

Doug,

Your experience doesn't surprise me. I posted years ago about the weakness of the domino joint. The Festool world just don't want to hear it. Don't just take my word on it though. See for yourself. Take a couple of 3/4×1 1/2" x 24" stock. Join them to make an"L" with a domino in the butt end of one joined to the 3/4" side of the other. Just a rail into a stile forming an "L" - Simple. Make another one still using the domino mortiser, but instead of using a Festool domino use a smooth surfaced everyday shop-made floating tenon. In both cases apply glue to both the mortise and the tenon just as you should with any MT joint. Let them dry for a couple of days then test them for strength against each other. Just put the stile end in a vice to hold component upright with the rail of the "L' up top so you can lever it. Go ahead and lever that domino joined rail and see what happens. The joint will release with sickening ease. Strangely, it will generally let go from the rail mortise which is long grain to long grain. Go ahead and try it. The good news that the smooth shop-made floating tenon joint is really strong. Usually the tenon holds and the wood in the stile splits. You get a joint stronger than the wood. I have tested this many times. Its not the same dynamic as dowel joint failure which is due to an almost all end grain glue contact. The only theory I have is that the impressions on the dominoes result in a reduction in actual wood to wood contact. I use my Festool Domino Joiner all time, but reserve the the Festool dominoes for engineered materials or low stress joints. If I need a strong joint in solid wood I never us the the Festool dominoes themselves. I generally make the shop-made tenons out of red oak: its strong and grabs glue way better than beech. Its also much, much cheaper than buying dominoes. Cheaper and far stronger. Its all good, just not good for Festool.


----------



## vipond33 (Jul 25, 2011)

mcase, do you believe it is mostly because of the smoothness, the freshness or the tighter fit of the shop made loose tenon? I carry no brief for the domino system (don't own one), just curious.
gene


----------



## Millo (Jan 19, 2010)

runswithscissors: I'm wondering the same thing


----------



## DouginVa (Mar 5, 2012)

On the project I took apart (described above) I noticed the glue kind of flaked off the dominoes. There didn't seem to be a tight bond between the wood legs and the dominoes.


----------



## mcase (Oct 31, 2009)

The dominoes are impressed with a pattern. Sort of like a biscuit. But, biscuits area compressed chips that swell up when wetted with glue thus forming a tight physical bond. The dominoes are just solid beech and the impression result in about half the surface not making actual wood to wood contact. I'm guessing, but I believe Festool impresses the dominoes so that they slide into joints more readily. They are designed I think to be applied in all humidities and the impression aid in getting them to go in when they are swelled. Maybe you just can't make a smooth tenon and send it all over the world an have it fit often enough. I don't know about that, but I do know that they are beech and impressed in such a way that half the surface doesn't make contact and they don't hold well at all compared to smooth shop-made red oak tenons.


----------



## vipond33 (Jul 25, 2011)

Thanks, I think I stand corrected. And impressed.
gene


----------



## pintodeluxe (Sep 12, 2010)

mcase,
nice info, it sounds like you have the experience with this system. I am a little surprised to hear it though. Even my biscuit joiner produces incredibly strong joints. Of course I am not using them for rail-to-leg joints.


----------

