Thread: Loose Tenon

Common technique, nothing wrong with it.

Look for discussions on Festool Domino (a machine based around loose tenon joinery) or Mortice Pal (a router jig suitable for making mortices).

Of course, the technique doesn't require those tools, they just make life easier if you're not into cutting mortices by hand.

There are also slot mortisers that will easily cut these joints. Fine Woodworking did a destructive test article a few years back comparing traditional tenons with loose, dowels, and biscuits. There was no functional difference between traditional and loose tenons in the test with regard to durability or strength.

Greg

Lends itself to router-made mortices because it's easy to make floating tenon stock with rounded corners that fit snugly in the rounded ends of the mortice. It's really a variation of the dowel joint. Also checkout Beadlock and Dowelmax which allow you to achieve similar results without a router - using a normal drill bit. Beadlock is a true floating tenon, Dowelmax uses a number of dowels.

I've used them a few times, mainly to replace dowel joints that have failed. As GregoryQ says, the FWW test showed no significant difference in strength from a traditional M&T.

Thanks for the feedback, I guess a couple of you have answered my main concern, is it as strong as a standard M&T. I have a large table project coming up, I might give the loose Tenon a go.

Originally Posted by silentC

. It's really a variation of the dowel joint.

In my opinion a loose tenon is far superior to a dowel. I think it's just slightly less strong than an integral tenon.

Originally Posted by Soredust

Thanks for the feedback, I guess a couple of you have answered my main concern, is it as strong as a standard M&T. I have a large table project coming up, I might give the loose Tenon a go.

Re the tabletop
- before the days of biscuits [which are mainly used for location as I believe from the info out there that they do not add significantly to the strength] I would join tops using a slot cutter in a handheld router. These slot cutters vary in size from 3.2mm up to 6.35mm in thickness of the trench they cut - pick a size that suits the thickness of your timber top. This actually fits very well with the thicknesses of ply available and will often fit or only require minimal sanding to fit the trench. I haven't had any problems in the past - they do the locating and certainly appear to be strong.

Should you decide to go this way just a couple of suggestions to avoid any problems.

1. ensure that your grooves/trenches are approx 2mm deeper than the loose tongue you are going to use - allows for the glue.

2. make the tongues a neat fit - so that they can be pushed into the trench easily - not too tight, not too loose - this allows the glue to do its job properly.

3. I would only trench up to approx 25mm from either end - this allowed for sanding, cleanup and that the tongues were not visible on the ends.

4. when making you trenches - ensure that you rout from the same side of the timber, ie run the router along all of the top sides or the bottoms. Should you be slightly off in your finding of the centre of your board then all of the trenches will line up and your boards should all be level.

Not sure if this is the info you were looking for but added it for your information.

Regards,
Bob

There particularily handy I think if your limited in tools. ie. its not straight forward for you to make the tenons.

uno, becomes as convienient as biscuit joints. Just need one small machine to router the mortises. Can buy dressed timber......dock to length squarely with a drop saw, and rout your mortises (good plunge router will do off fence)

Basically, means you can butt joint anything strongly. And butt jointing is far quicker than making tenons. (still think its cheating a bit, even though I use them a lot. I get alot more pleasure out of traditional M&T)

Originally Posted by Frank Drew

In my opinion a loose tenon is far superior to a dowel. I think it's just slightly less strong than an integral tenon.

Quite correct. It's a variation on a dowel, in that the loose tenon is like a wide (or deep) dowel, but it has much more wood, and usually much more gluing area to give it more strength.

Funnily enough, the best way to repair a broken tenon is to replace it with a loose tenon. Works well and has been the repair of choice for centuries. It wasn't done as a matter of course previously because it was simpler with hand tools to only chop one mortise. With today's machines it is a valid choice of joinery and cost effective. With the advent of the Domino and other machinery it is most likely more cost effective in some production and small shops.

Once again, thanks for the great info. . I can see how the Loose tenon would be the easy way to go for short table aprons, ie the ends, but would be rather difficult for the longer side aprons, unless you have the Festool Domino? (sp). As the table I am building will have 1800mm x 1800mm aprons, I may have to do standard M&T .

I was in Carbatec today picking up my new thicknesser and noticed the Festool Dom', it didn't have a price tag but I can't imagine it would be cheap.

Originally Posted by Soredust

I was in Carbatec today picking up my new thicknesser and noticed the Festool Dom', it didn't have a price tag but I can't imagine it would be cheap.

The German translation of "sticker shock" is "Festool"

Despite the high prices I do not see too many owners say they do not provide excellent value; there have been some, not many though.

To get started with a Domino will cost around $1500 although there are many other ways to get into floating tenons - the router being the first that comes to mind.

Have a look at the Beadlock system. I purchased a starter kit for under $100 with enough tennon stock to do several tables. Simple to use and good solid tennon joinery. I've since purchased the router bit to make my own tennon stock. For the amount of M&T joinery i do it suits me well.

Originally Posted by Frank Drew

In my opinion a loose tenon is far superior to a dowel. I think it's just slightly less strong than an integral tenon.

I didn't say it has the same strength as a dowel joint, I said it was a variation of it. A dowel is a round loose tenon. Maybe I should have said a dowel is a variation of a loose tenon.

I have seen test results that indicate a loose tenon is stronger than a standard tenon, weaker than a standard tenon, the same strength as a tenon. Dowelmax have test results on their website indicating that their multi-dowel joint is stronger than either. So it depends on who you want to believe. I reckon all you need to know is that a loose tenon is strong enough.