what is the best way to make this cut

[Dave Richards]

Am I the only one who thinks expansion and contraction are bound to be a problem here.

Nope. I was just thinking the same thing and wondering why the tenons are exposed.

[Warren Lake]

if you can cut the cheeks as shown on the table saw then just cut the whole thing put dadoe blades in fast and consistent

[Bob Cooper]

well i can definately move those legs in so that that mortise isn't exposed...in the original design those legs are pulled in 12" but i cannot afford that kind of overhang.

let me ask you this though...if you think there's a wood expansion issue here wouldn't there be one on any kind of tight mortise/tenon? i've never cut any...maybe they just aren't so tight that its' not an issue

if i do this then cutting this on the tablesaw and bandsaw i think is the quick way to get it done.

[Bob Cooper]

Doing it with a router is simple. The jig you make to set the length of the tenon just needs zero clearance stops on either side so that there is no break out.

OK...Wayne...i'm not following. My thoughts were to just attach a template on the end of the post the same width as the tenon. Then have a straight bit with a bearing on it that is on the collet side if the router and just cut down in stages until i went down the length of the tenon. So my router is resting on end of the post the entire time. i'm not sure what the stops are for that you're mentioning.

[Dave Richards]

let me ask you this though...if you think there's a wood expansion issue here wouldn't there be one on any kind of tight mortise/tenon? i've never cut any...maybe they just aren't so tight that its' not an issue

The tenon would swell in the mortise a little although the effect would be less dramatic than on the whole leg because it would be smaller. The main thing is that it looks like you intend the legs to be flush with the end of the bench top. The top won't expand and contract in its length but the legs will expand and contract across their width so the two won't remain flush even if they start out that way.

[Warren Lake]

you dont build stuff flush you leave a reveal, the top should over hang and the mortise stopped the rail as well is shown flush in the drawing and should be inset

[Wayne Lomman]

DSC_0471.jpg
Bob, you work with the leg laying flat on your bench. I have attached a mud sketch of how the jig is constructed. You do one side of the tenon at a time. This is why it is important to have accurately thicknessed timber. It is designed to us a simple straight cutter. The edge of your router base plate rubs against the fence. The router sits on the face of the stops. The stops are wide to give plenty of support for the router. Set the length of the stops so that they are flush with the end of the post. This means it is easy to set up for every post without measuring every time. When you start machining, work from the end of the timber back to the fence so that you always have material to support the router.

As I have already said, this is a jig I have used for any long awkward stock requiring a tenon or lap joint. You only need 3 pieces of scrap with one straight edge on each piece and it is done.

With regard to the shrinkage discussion, it presents the same issues as a breadboard end which doesn't seem to bother a lot of people. Cheers

[andy bessette]

OK...My thoughts were to just attach a template on the end of the post the same width as the tenon. Then have a straight bit with a bearing on it that is on the collet side if the router and just cut down in stages until i went down the length of the tenon. So my router is resting on end of the post the entire time...

No. You would not want the router balanced on the end of a tenon.

[Bob Cooper]

you dont build stuff flush you leave a reveal, the top should over hang and the mortise stopped the rail as well is shown flush in the drawing and should be inset

ok...Dave/Warren...i totally get that and typically i don't try and build anything that mates w/2 surfaces being flush. But in this case i'm following a design by Chris Schwarz...see the picture below. You can see how he does in fact have the front of the legs flush with the front of the bench...same thing w/his stretchers. So when i shortened the bench i just removed the overhang and had it flush on 2 sides.

in the end...it's a workbench and i hope it looks well used (beat up) and not pristine so it may not matter too much but i appreciate the feedback and questions from you guys.

[Bob Cooper]

Wayne...ok, that makes perfect sense and a whole lot more stable than what i was thinking. picture was worth a 1000 words.

[Dave Richards]

There are times it makes sense to put the leg flush with the edge of the top as in the case of a traditional workbench as you show, Bob, but that's at the front edge of the bench which you have long grain above the leg. You don't want to do that at the end because as I said, the top won't move in that direction, at least not nearly as much as the leg will expand across the grain.

[Tom Bain]

DSC_0471.jpg
Bob, you work with the leg laying flat on your bench. I have attached a mud sketch of how the jig is constructed. You do one side of the tenon at a time. This is why it is important to have accurately thicknessed timber. It is designed to us a simple straight cutter. The edge of your router base plate rubs against the fence. The router sits on the face of the stops. The stops are wide to give plenty of support for the router. Set the length of the stops so that they are flush with the end of the post. This means it is easy to set up for every post without measuring every time. When you start machining, work from the end of the timber back to the fence so that you always have material to support the router.

As I have already said, this is a jig I have used for any long awkward stock requiring a tenon or lap joint. You only need 3 pieces of scrap with one straight edge on each piece and it is done.

With regard to the shrinkage discussion, it presents the same issues as a breadboard end which doesn't seem to bother a lot of people. Cheers

Yes, this. It’s not the fastest way to make the tenons, but it will leave you with very clean shoulders and cheeks. It’s also very easy to dial in the thickness by adjusting the plunge depth. You can make a test tenon first to make sure the fit is how you want it, and once the plunge depth is set, voila.

[Bob Cooper]

i guess the one area you do by hand is cleaning up the corner...right at that inside corner?

[Tom Bain]

i guess the one area you do by hand is cleaning up the corner...right at that inside corner?

With Wayne’s jig there should not really be any cleaning up required. You can route slightly into the jig on either side, just make sure the jig stock is thicker than depth of cut as Wayne put in his drawing.

[Wayne Lomman]

Tom is right. The edges of the jig are sacrificial, just not too much or you lose support area. No hand cleaning required. And yes this is not the quickest way to tenon, but it works with minimal equipment on site for modifications to components and is a handy technique for heavy and/ or large timbers. Cheers