Question on tenons

[Assaf Oppenheimer]

I am ready to cut the tenons for my workbench. These are big beefy 5 inch by 4 and a half inch legs.
I know that usually the first step is to square the endgrain.
I got to thinking. The reason to square the endgrain is to use it to reference the shoulder with the marking guage.
These are honking tenons with big shoulders made of hard maple. Trimming the ends seems like an awful lot of work. Could I mark and cut the shoulders using a combo square? If the mortises end up a tad deep i dont think it will matter with such a beefy joint. Am i missing something here?

[mike stenson]

I am ready to cut the tenons for my workbench. These are big beefy 5 inch by 4 and a half inch legs.
I know that usually the first step is to square the endgrain.
I got to thinking. The reason to square the endgrain is to use it to reference the shoulder with the marking guage.
These are honking tenons with big shoulders made of hard maple. Trimming the ends seems like an awful lot of work. Could I mark and cut the shoulders using a combo square? If the mortises end up a tad deep i dont think it will matter with such a beefy joint. Am i missing something here?

I intentionally trimmed my tenons short of their mortises, especially since I drawbored em. The strength comes from the sides and the cheeks, not the ends anyway. Square ends help make everything easier. For my build, they were referenced off the bottom of the legs, as that established bench height.

Here's how I did mine, and why I didn't care about having a gap at the top
https://photos.smugmug.com/Woodworking/Shop/Roubo-Bench-/i-jzjRBWf/0/e3cad251/M/IMG_7948-M.jpg

[Derek Cohen]

I am ready to cut the tenons for my workbench. These are big beefy 5 inch by 4 and a half inch legs.
I know that usually the first step is to square the endgrain.
I got to thinking. The reason to square the endgrain is to use it to reference the shoulder with the marking guage.
These are honking tenons with big shoulders made of hard maple. Trimming the ends seems like an awful lot of work. Could I mark and cut the shoulders using a combo square? If the mortises end up a tad deep i dont think it will matter with such a beefy joint. Am i missing something here?

Assaf, absolutely mark with a square. Just remember to score one side, and then two adjacent sides - and not mark the shoulders around the leg in a continuous direction. The latter will end up inaccurate if the sides are not parallel.

I would leave the length of the tenon just short of the bottom of the mortice, and pull the two together with a drawbore. A seated shoulder should add to the rigidity.

Regards from Perth

Derek

[Rafael Herrera]

I know that usually the first step is to square the endgrain.

When you cut the legs to length, the squarenes out of the saw cut should be enough. These are blind tenons, no?



The reason to square the endgrain is to use it to reference the shoulder with the marking guage.
These are honking tenons with big shoulders made of hard maple. Trimming the ends seems like an awful lot of work. Could I mark and cut the shoulders using a combo square? If the mortises end up a tad deep i dont think it will matter with such a beefy joint. Am i missing something here?

No, the ends of the leg are not references to mark the tenon. Measure the length of the tenons you want and then pick a reference side, use it to mark the shoulders using a square. The tenon length and mortise depth need not be accurate to the mm, the tenon must fit you can leave a small void inside, 5mm, 10mm, whatever you want.

I'd suggest you look into the concepts of reference faces and reference edges when preparing lumber.

[Assaf Oppenheimer]

Thank you Derek, this is a tenon that will sink into the bench top - the top is 5 feet long so it only weighs about 60 pounds. I'm hoping that that plus the 2 lag screws per a top (its a split top) will do the trick.