Angled Tenons

[Dave Rosner]

Ok i'm about ready to give up on the following design that requires angled tenons. The 4 splayed legs are 10 degrees in each direction and i've tried a few things including dado, by hand, etc. Problem is the layout is almost imposible as there isn't a consistent edge/face to reference to get the angle of the tenons correct. My legs are 1.5" square and i'm shooting for a 1" square tenon.

I've searched and searched and only thing i can find are examples for chairs but those all have round mortises. How do i cut these tenons so they are square to the compound miter that will ultimately be the shoulders of the tenon?

430712

[Jamie Buxton]

I'd solve the problem a little differently. I'd make the tenon on the leg straight, and make the mortise through the table top angled. Further, I'd make the tenon floating. That is, I'd cut a mortise into the end of the leg blank so that the walls of the mortise are parallel to the faces of the leg. You'll have nice reference surfaces to do this cutting. Then I'd crosscut the end of the leg with the compound angle you need. This crosscut creates all the shoulders at one time, and ensures that they're all in one plane. Then I'd plug the floating tenon into the end of the leg, and into the angled mortise in the table top.

[Dave Rosner]

I’m gonna try the angled mortise tomorrow. Sounds hard to get right but seems that is a very typical approach for this so maybe not as hard as it seems.

I like the idea of a floating tenon but can I create an end grain mortise? I’d worry about yet another element that I’d have to get perfect to line up. But it would make getting the through tenon look perfect if I can pull it off. I can easily mill the floating tenon perfectly to the angled mortise.

[Kevin Jenness]

Given that the top and base are both joined to the legs, having the tenons (whether integral or spline tenons) parallel to the leg faces will make it difficult if not impossible to assemble. The tenons should be at right angles to the top and base faces. Splayed tenons would work if joined only to the top.

The tenon layout should not be that difficult using a bevel gauge and adjustable square or mortise gauge, and the tenons can be cut by hand without any jigging. Alternatively, the router jig used to mortise the top and base could be used to mill the legs for spline tenons after the compound angled ends are cut, but you would have to devise some clamping bocks to hold the jig and legs in position. Squaring up the leg mortises will be more of a challenge than those in the top.

The project would be much less demanding if the base were omitted. Given the small size of the table it should be strong enough given the proportions shown in your drawing. I used to eat at a break table with a 1 3/4" x 36" x 120" pine top and 2" through tenoned hardwood legs, and that took a beating.

[Jamie Buxton]

[LEFT][COLOR=#222222][FONT=Verdana]Given that the top and base are both joined to the legs, having the tenons (whether integral or spline tenons) parallel to the leg faces will make it difficult if not impossible to assemble. ...

Only in theory. In practice you can make it happen.

[Kevin Jenness]

Yes, I see now that loose tenons can be driven in from outside.

If the loose tenons are square, their compound angled ends will present as a rhombus when flushed off at the top's surface.

Clamping up will be fun.

[Charles Taylor]

Laying out is not a difficult task with a bevel gauge, square, and a sharp pencil or (better yet) marking knife.

There are lots of ways to cut angled tenons. One is a commercially available jig like this for the table saw:
430762
On the cheap you can put together a purpose-made jig to hold the workpiece at the proper angles on the table saw or the router table. Here's one I used to make tenons on curved workpieces.
430763 430764

If you opt for angled mortises instead, jigs can help you there too.

[John TenEyck]

One of these would allow you to make angled tenons quick and easy.

https://lh3.googleusercontent.com/oERp7Ai3Q-Jk2jckSYgwYDMqUFDaMxjZkQyS9Sz-7BZdnzHND1vIGDLqgt8lyocsbwRYej1D-cfqjcm6RZLFs_hSWe29vA8mmEv9B6AUhoa4r64aZK83RoScf3j Z2gsZy-Et2xtnjHmXesMXZV3R-_gNXr6lrX46COSHQkCWB-nLzS5kTSiv_bF_IoPvDAH8DQcXcuLAGYfghF3qGdq5XulaGi5Z GebfKUx9F_Ze04Hc4xbpXGMJwjoAHQaYTLxiBI0ljIBfxqtcIc P3lg16kBL6K8-XS0ioNkvDWZRQFt0fc6mJ9FnRVlAAch1TVTJGqKwE7c7X_AqP9 ZqjdOgCdBDZyIgU3AeomM0fD_RT8TW-J5lpngJ8o7JKrpOYVgxbvD4MqJtvG_I9a-0miRYXiZnWKjghKuUNycUdTgKbTeNsG21Zw7LvRkh3TRrGG4Ct djOcVWjyz7pckH0InchwKRFT5azTYlyjN4Q_KcixUloc-bQvXQ8l5vUO_x4Zy8coFYBJddx3NsFuOKrehDicATgd_dkrAPq 6tAgKvB3dhbufITvvyN_9gV_dO0pst28DjLIQgyy56yLxNt5aM 7kO4Z2gtmWvnj0Gj0ld68qvnb2koI_j5yngZzkOTnkHorzRCJ5 NWmodB22AQP1wqF6REmL6ykfzuZ9B8GyspsELuRcRSgG-yuvERoXosiaJCgJA04qmvqqGxi96Mxek32KDO0E_yXMM5Z9erL Ijzo9YbubA5FA1OOO_0PQF=w835-h626-no

The X-table tips up to almost 50°. Here's a shot of setting the table to maybe 10°, can't remember for sure but it's similar to your need.

https://lh3.googleusercontent.com/ShClM3ZU_9cLt_LbDHuDf7gc9iIzVqDBzTwVQTFxstQbcRg4wg e28cpH1GOBfM_aK70shQCfU-Fl1bJmQzeuxjhVmhm0YjV5y9fBYKliOZCBuBaJ7huRM-_JsPqUjycYLyEmKOnumqHVyeuf8BGUyKUWPlDR0_47LZSYvY61 royxg9nrKh-Xl7cCkcg9b4s_oEcJkVWNgafpEfLi0IIamRJUjeEczelNllzni 60jbWXF1wacYOQwU2HZb9PGn8Dszfamc2roI1Amq9SHG48eYW0 As-2Pj63MeQPMpJdqlaq96yQ2xPzgiq3BvkGKtPhRxMiKQdGNXSZR lsFob4bXl1_WQo0BXR7avO8SpqcYkFZ-Y19i5HC0FBlLdHBqc-nDtw5T-7_1fviOTaAr1nl1k-vuquqbX-hWE_spezSpJagSlOjCQTQ7WAwsZOzSuQTkaEaz5v0smSeqnAnw ZBRGg5TAwrik_wBbO-uc81cJgwcoBQb4kwVPKlqoRmSoqWvbtoLlnsukqP0CiU0xkBZX Cc0SukTaETsApRrExkZ_HSGdk9dJlTf6dAQuQE8KeFS5qUSQkD 8hlrBbxKT1jo2U2v8DXzSzdf_R8I3M2zwK8HydkGhoeyzeLJnR ZM7MGzKe47Xh4QI8vbZh9wGNOqWcM0zJ2n55S-xTak3A_HihTzkuBapc7WMjfAm5NI7gj3tl93zYjTNt7kOrWD3M 4fthLMD0MToYYHgdL_sipGwDeFxtbY_M9KV-_LX2=w640-h480-no

And here's a photo of the loose tenon I installed in the end of the piece after that mortise was cut.

https://lh3.googleusercontent.com/caYV5BO7HDtAIYQUsfzcAzyU9sefd-vKby47qsTzq0TIK7MlOQyGsOYIDW41_E4G4j4KcyaYjjpj1DgO MAT6btuUNIWxWfjwo3yaDXtDxIlIjeDTIVp9--zFRq1een6PCnpPCHu9Esdb2mjoMI4cdL6adTKxBSPAT424-QIdTfdDWpr1WhR9wZ3wmlGyaBP5zOWulrCLg3nQU4hUDjBGlI8 fiyGQ9biSwCAqen1JkYwzT00M4cMRpOzTYNNFja1Kc4hXWvOvD EzajkiGHDcyuwWJaH5vfYBtlZFpnTGL2cdPKBQjAjk22Yb7giS 9nd_N9QyBFSmiPW-xzuAS1OBEpJ53KZWpZDL8IXKXxl2Kcwt5vcpo7XhFvrnZInAVM q3OimaNlnAlDH0eqt9pUCBYRees3G-_xCdcVDRR5v3YR-ofRmIjviiGhsOEIbSk6rTkDkzGo5pIOH9UhSdjzdMi4-f9kfEnVAm4CW9QpB4gXWSONSY1879CHsqrmHFqVuAyjuSmPH9h Im8kG3ZUWyqL5Ip1KtzRvBjr5TnIENybWO73-8Gy2oSjucDEO9irCopUj415gxhE7O5whHGprkCoVdwrAei4cZF cI4s7RkTbRK-RQpxpFOqz0R8voqrKsywcAPs9oZ2zCSEwv_6Z9nzFpjFY27Z2t zMWD5XmyT02Q4caxJ71JTHIIsg0SHOKvmfq49Nd-i0AzINlT4tKrUWJqD-tYq5JvE0cn6p0lGaN-aCnrqJUNcK8mPnh=w640-h480-no

The notes on this photo of the tenon confirm it is actually 10°:

https://lh3.googleusercontent.com/wnIPuJ7uI0amA41NDm8B7LCodA_F15UfbDdC9d32kcHkarR184 mKXofIQ95a638SNdY5u69GGNbU8aDvJv12B6lXIubSFPp0rzLT lWi7mj_2XTyYPwA2MKp5HxzibSbbWYlAQ54l3LsJ6QsaWXCcHV bgIac3xpG0XKT4n1o_-TnbpMReBtL6-uQsHQxaE0dYwFi-APpkklrF706GKtQZauOWFo1_H034EsYT9lve9CncAgMT-H1TS8ooLMuO-uTNkiBpdLF2eIz3dh-Myj1b1iECc51yMzRQranaeaUyQFLw2B9CZiD09tKAzzoprg_oC _Nqv2PN6Wo_8OsMkTMgvo-9_Aa26orA_mOPy2MP7uQQ4xPmrHFAw7KDrad-fXVi8bA0vcZcyKTfOiP5lqlgg76DFUoOY_XAP28bLmnAq4d14p BA2Xm96VZhodk2OVoPXGl-ir4xd0Up5WWEt5uic21cMeMQ48Crzbvn5JQZav-u9z5t4nTgtzf74FtgrSP55HMVR1WCM0XGkYbtNqcKpWNqiCKhj VQkJ0ZO36sxi6gF4mRm6v6v8HQXyS-J21S6WjMRgT_YFzboFW3M4Fj_fNqIx2cGlAaM7or7UzTwJ6fX6 dZOSIboWoYetHxaEkDkj5q2rBmciHS_GpDqn4LnAw1ONqWfwA3 WTw_4wdLCcKDB-i6Xe4OQai_Xywt5Y5V5gd7XJ-zZ1KSjbft_F-advKX1PcOQJqQXmUhwmkwDQ-_5eIxY_saz6P0_=w470-h626-no

I normally use loose tenons, but you can cut integral tenons, too, it just takes a little more work. The angled cheeks of the tenon are cut on the router mortiser and then the shoulders are cut by hand, BS, TS, or RAS.

John

[Dave Rosner]

That machine would be quite helpful indeed!

if I do loose tenons could I see have a straight mortise in the table and angled in the leg? Getting the leg angle perfect would be easier with a router and simply getting the shoulders in plane with my table that will hold to down. Probably can only go so deep though...

[Rod Sheridan]

I cut angled tenons on the shaper by tilting the spindle or changing the crosscut fence angle, or both....Rod

[John TenEyck]

That machine would be quite helpful indeed!

if I do loose tenons could I see have a straight mortise in the table and angled in the leg? Getting the leg angle perfect would be easier with a router and simply getting the shoulders in plane with my table that will hold to down. Probably can only go so deep though...


Yes, the joint I showed has a straight mortise in the "table". You can make the mortises as deep as the stock permits but there's no need to make them really deep for that application; the top sits on the legs so the only time there is any stress on the joint is when the table gets picked up.

You can build a flat table version of my machine from free plans at the bottom of the page at this link: https://sites.google.com/site/jteneyckwoodworker/current-projects/horizontal-router-mortiser Just add a 10° wedge to the X-table and you can cut those mortises (or integral tenons). Or I'd be happy to sell you the machine shown above.

John

[Thomas McCurnin]

Fine Woodworking March 2017 has an article by Jeff Miller with detailed diagrams of making a jig for a handheld router to make angled tenons. The jig is very simple to make, but is a one-off jig, that is to be used on a specifically sized tenon. It uses a hardwood guide strip and a guide bushing for the tenon thickness. It uses wedges to make the angles. It would only take a weekend to make the jig. I will note that I would practice on making straight tenons with the jig first, before moving on to angled tenons.

I am perplexed by the problem because if you can draw the tenon on the wood (e.g., layout), one should be able to cut the angled tenon using either saws or splitting the tenon with a sharp chisel.

In addition, a loose tenon solves a lot of problems. Jeff Miller also has a jig to make angled mortises although I can't find a picture. It is probably similar to one Michael Fortune made in Fine Woodworking March 2008.

That said, I am reminded of the saying in the Army that it you are remaining calm while everyone around you is panicking, then you obviously don't understand the problem.