Thread: Tell me how you make your floating tenons....please

Hi Mr Tripper,

As the proud owner of a domino, who sometimes likes to use "species specific" tenons, here's how I do it. (You can see some more in the Festool forums , I think under hand made tenons as a thread)

Its simple really, depending on the size of tenon you want. I make 5mmx20mm by any length you want by cutting the appropriate timber to width and depth and length. For the small tenons I use a dremel router table and pass the timber over a rounding or beading bit and there you are!

For thicker or wider tenons, ( though 10x32x whatever length works OK on the dremel)you are best to use the real router table, again with a bead or roundover bit and using a grooving bit, make the flutes for the glue to escape through.

Hope this helps.

Regards

Rob.

Tripper,

In a book I have tests were run to try and settle this argument specifically for door joinery. They were conducted by an engineer at a Woodoworking company (Benson Woodworking) in the US (New Hampshire).

All tests were compression tests conducted on cherry using yellow glue and on a 7 x 12 rail and stile section a half inch wide. Joint methods tested were:

• Lag Bolt
• tongue and groove
• dowels
• loose tenon
• mortise and tenon
• two biscuits and
• three biscuits

Results were in the order above with the lag bolt being the weakest and three biscuits the strongest. The Loose tenon was basically identical to the M &T with both showing a gap at 1,200 lbs. pressure and outright joint failure at 2,600 lbs.

The dowels gapped at around 1,200 but outright failed at 1,700. Two biscuits failed at 2,700 and the strongest was 3 biscuits failing at 3,000 lbs pressure.

The authors overall appraisal was that both loose tenon and M&T were the best joints to use because while the biscuits were stronger overall, the failure of loose tenon and M&T was generally such that the joint still held together while with the biscuits the failure was complete and sudden i.e. snapping in half suddenly.

This is just one semi - scientific survey, sure others might disagree but interesting none the less.

Cheers,

It does. Ta Rob. confirms things.

Spose the only issue is in setup . Roundover bits diameter same as tennon thickness......etc etc.

That domino's sounding handy alright.

Have you ever tried wedging through round tennons ? Thats what I plan on doing mostly.

Thanks Brett. Interesting. Gives me an idea. New that about dowels. Doweled chairs always falling apart. Didn't realise just how strong biscuits were though....If only they contributed some asthetic appeal. ...poking out tenons look good uno !

So, you reakon pinning the loose tenon would be of little help in terms of strength ? imagine so. Not that it really matters I spose. just curious.

Tripper,
I've done through tenons, wedged. If you look at Woodwork pics "Shakered not stirred" you can see the tenons I used and the wedges. These tenons are reliant on the wedges for structural integrity. I have also used through tenons cut by the Domino and inserted my own tenons (as opposed to the domino biscuits) as a complimentary colour. How you want to approach these would be determined by the width and height of the mortise, which in turn will be dependant on your ability to cut the required width for the aesthetic appeal you need form the face of the tenon. In the woodwork pics "Spicerackius Humongous" thread, you can see red gum used against Crapiata in a small drawer.
On dowels, I would think you could make these as round tenons by using a rounding bit with the appropriate diameter, then filing, sanding or passing through a daowel sizer to get what you want.

Your right about the Domino though.

Hope this helps also

Regards,

Rob

I've only ever used floating tenons in repairs. I ran a bit of 1/2" tassie oak thickness over a 1/4" round over cutter on all 4 long corners, and just cut off lengths as I need them.

One day I s'pose I'll get a smaller repair to do, but until then.....

Originally Posted by apricotripper

Have you ever tried wedging through round tennons ? Thats what I plan on doing mostly.

Jake, do you mean round tennons or tennons with rounded edges?
If the latter, tapering the round part of the mortise while keeping the right radius might be a bit tricky.

ian

Hi Ian,
It is possible to cut the mortise to the minimum width, then use a Dremel sanding disc to expand the "back" of the mortise to fit. Not terribly elegant, I admit, but with a little practice, quite functional.
Also, I forgot to mention that through Dominoes as joints in frames is my interpretation of Lignum's idea. Credit where credit is due.

Regards

Rob

Originally Posted by Flowboy

Hi Ian,
It is possible to cut the mortise to the minimum width, then use a Dremel sanding disc to expand the "back" of the mortise to fit. Not terribly elegant, I admit, but with a little practice, quite functional.
Also, I forgot to mention that through Dominoes as joints in frames is my interpretation of Lignum's idea. Credit where credit is due.

Regards

Rob

Hi Rob
I tried the "through Domino" joint two weeks ago and found that many of the mortises were filled with compacted saw dust. Any idea of what I might have done wrong?
(yes, the vac was attached and turned on)

The joint I'm visualising for Jake has rounded mortises and the wedges would expand the tennon topwrads the rounded ends


Ian

Hi Ian,

I have found the same myself, especially with the larger cutters and a wide mortise. I think it has top do with the efficiency of stock removal by the cutter before it actually gets to the vacuum. Remember only the very front of the cutter is actually cutting, the rest screws the sawdust back to the vacuum.
I have noticed the same thing using a CMT 12.7mm spiral upcut in the Leigh FMT jig. All was fine until there was space around the cutter which negates the draw of the vacuum, then I had a 30mmx65mm hole full of dust:mad: . This also happened when I was cutting a 30mmx65mm through mortise with a 10mm cutter on the Domino. So, your not doing anything wrong, its just physics at work.

Hope this helps

Regards

Rob

I always make my tenons out of wood and put them in a bucket of water to see if they float. If they do, then they are floating tenons, if they don't they ain't.

Originally Posted by ian

The joint I'm visualising for Jake has rounded mortises and the wedges would expand the tennon topwrads the rounded ends
ian

hi Ian,

yes, we're thinking the same......With what I've got the easiest method to do the mortise s always been just pushing the bugger into a router bit freehand with plenty of downward pressure. Took a quick photo from the shed just now.

See, I bought this router chuck attachment to go on my shopsmith (one of those universal machines that turn into drill press/lathe/tablesaw etc)....Takes 1/2" shanks. Up till now I just buy router bits with 1/2" shanks and mortise with it.....end up with round ended mortises.

Unlike in the picture, You clamp on a backing board, to stop tearout for when your making through tennons.

Want to get some of those flash upcutting spiriling bits soon. Apparently they cut nicer.

Anycase these mortises are quite clean and accurate when done on the shopsmith. So, I'll stick with it.

Just have to round over those edges of the floating tenon to match the mortises.....With normal non-floating tennons, you just file them round, but that seems a bit fiddly with short stubby tennons sitting in the vise...

..thinking will probably just buy a bead router bit to match and use it on the router table....Just rip up a lenth of the stuff, and cross cut off all the tennons I need (imagine thats how its done)..but was wondering how else I could do it, and maybe save on having to buy these bead bits.

Thinking at one stage I could do it with a bead bit in a combination plane, but that means sharpening this profile just right....and wastage in thicknessing out the fillet needed to make the plane cut. Router bead be much better....but, hoping there'd be another way. Someway of doing it with what I've already got.

I'm sorry I can't offer much of a conversation on the domino or dremel. I've never used either. But sounds interesting.

Jake,

I'm a floating tenon fan. After cutting the mortises, I get a piece of offcut same species and cut to general dimensions, but in one long piece. So if the mortices are 8mm by 40mm by 20mm deep, I'll make a couple of long pieces 8mm x 40mm, by whatever length of offcuts I have.

Then run the long piece through either a bead bit (if you have one the right size) or a small roundover bit. If it's a small job, a sharp block plane can do the roundovers in the time it takes to set up the roundover bit.

You can test fit the long pieces to make sure they're the right size for the mortices, and adjust if needed.

Clamp a stop block to the table saw fence 10 or 20 mm in front of the blade, and whatever depth you need. For 20mm deep mortice, I tend to use 38mm floating tenons (because I'm not always very accurate, and hate tenons that are too long). Then cut the tenons to length. The block will keep the tenons from binding between fence and blade.

Takes about 15 minutes to cut a couple of dozen tenons, and it's from the same timber and etc etc.

That's how I do it, anyway.

Tex

Hi Tripper,
The joint I'm visualising is the same as Ian, I got confused by the dowels:confused: .
I'm not sure you will gain any real benefit from spiral upcut or dwncut bits in your system. First they are designed to pull waste away to the surface (hand rout) or down to the table. The big advantage they have is the really clean job they do of the bottom (or top) of the mortise. Since you are making through mortises, you may be better to think about either a longer 1/2" straight bit (say 1 1/2" up) and a backing board to clean the through cut. You are probably aware already (I'm good at stating the bleeding obvious) but if you buy a rounding bit you can convert it to a beading bit by changing the bearing diameter.

Regards,

Rob