Wedged through tenons

[tibi]

Hello,

This is the first time I am going to cut wedged through tenons for a sawbench. They are 40 mm long, 12 mm wide and 40 mm deep + 8 mm protruding past the other end of the through mortice. I have already cut the mortices (doing my best to look neat from the outside face). I am doing them in beech with walnut wedges.

Do you have any tips how to make them right on the first time? There is a lot of conflicting advice on youtube, so I would like to know what works for you.

e.g.
- wedge angle
-offset for splay on the show face of the through mortice (is it the same as desired width of the wedge on the show face)?
- splay depth ( to the middle of the mortice, to the base?)
- relief hole location and size
- kerf distance from the edge of the tenon

-kerf width and position relative to the hole (center of the hole or inside tangent line?
- how to make wedges look equal after hammering them in (not Laurel and Hardy version)
- how to cut wedges with a hand saw

- any other pitfalls I am not aware of that can ruin the piece.

Thank you very much.

 

[Jacob]

Hello,

This is the first time I am going to cut wedged through tenons for a sawbench. They are 40 mm long, 12 mm wide and 40 mm deep + 8 mm protruding past the other end of the through mortice. I have already cut the mortices (doing my best to look neat from the outside face). I am doing them in beech with walnut wedges.

Do you have any tips how to make them right on the first time? There is a lot of conflicting advice on youtube, so I would like to know what works for you.
View attachment 146727
e.g.
- wedge angle
-offset for splay on the show face of the through mortice (is it the same as desired width of the wedge on the show face)?
- splay depth ( to the middle of the mortice, to the base?)
- relief hole location and size
- kerf distance from the edge of the tenon

-kerf width and position relative to the hole (center of the hole or inside tangent line?
- how to make wedges look equal after hammering them in (not Laurel and Hardy version)
- how to cut wedges with a hand saw

- any other pitfalls I am not aware of that can ruin the piece.

Thank you very much.

Overthinking again!
The fancy wedges and tenons in you pic are just for enthusiasts and magazine articles, not to be taken seriously.
The normal way is to chisel a wedge shaped hole in the sides of the mortice to about 2/3rds down.
Make wedges to match but longer. Dip the end in glue and hammer them home. Trim the length and the end of the tenon with a tenon saw and finish with a block plane.
PS if you want an angle, say 10º? Doesn't really matter much.

 

[Jacob]

Overthinking again!
The fancy wedges and tenons in you pic are just for enthusiasts and magazine articles, not to be taken seriously.
The normal way is to chisel a wedge shaped hole in the sides of the mortice to about 2/3rds down.
Make wedges to match but longer. Dip the end in glue and hammer them home. Trim the length and the end of the tenon with a tenon saw and finish with a block plane.
PS if you want an angle, say 10º? Doesn't really matter much.

I just googled "wedged mortice and tenon" and was amazed to find that ALL examples were of the fancy woodwork mag variety, which nobody ever used in the past. Gave up scrolling down looking for a normal one! How weird!
Trad woodwork is being written out of history!
wedged mortice and tenon - Google Search

 

[rogxwhit]

That relief hole in the pic is a waste of time and doesn't do anything. People are always making silly stuff up these days.

There are various configurations - one is to drive the wedge into a kerf, another is to have the wedges flanking the tenon - in both cases the mortice is splayed. Careful measuring is good - ideally you want the tenon to be gripped most tightly near its shoulders. It can be useful to make the wedges from wood that's harder than the tenon.

 

[rogxwhit]

 

[Sebb]

i thought the relief hole is to stop the tenon possible splitting as the wedge drives into the end grain, makes sense to me whether its worth doing depends on the application though i guess

 

[johnnyb]

I'm with Jacob on this. that method adds many ways for this great method to fail. if you must do it that way then take extra care. especially as the wedge could bottom out.

 

[rogxwhit]

i thought the relief hole is to stop the tenon possible splitting as the wedge drives into the end grain

How is a hole going to do that? If the tenon root wants to split it'll split anyway beyond the hole. The hole doesn't do anything.

 

[Sgian Dubh]

Overthinking again!
The fancy wedges and tenons in you pic are just for enthusiasts and magazine articles, not to be taken seriously.
The normal way is to chisel a wedge shaped hole in the sides of the mortice to about 2/3rds down.
Make wedges to match but longer. Dip the end in glue and hammer them home. Trim the length and the end of the tenon with a tenon saw and finish with a block plane.
PS if you want an angle, say 10º? Doesn't really matter much.

The "just for enthusiasts and magazine articles, not to be taken seriously" comment from you is interesting. I notice rogxwhit seems to express somewhat similar sentiment towards driving wedges into a couple of saw kerfs with a relief hole at the bottom of the kerfs to form the wedged M&T. I've come across the preferred method of working you described many times, and in almost every case it's been comments made by those from a predominantly joinery background rather than a furniture background.

The general form illustrated by tibi in the opening post is the form I've used in the vast majority of my work where a wedged M&T was required. In truth, that form always seems to have been the most common approach taken by makers in the various workshops I've worked in over the decades, and I think it reflects the fact that those workshops have been primarily furniture workshops rather than joinery workshops.

Incidentally, I don't think either method is the only 'right' one. Your preferred method is quicker (no additional saw cuts and hole boring required), but maybe somewhat less elegant or pretty, and arguably somewhat less secure. You will possibly come back with a rejoinder that I'm one those prissy enthusiasts of pretty over production, ha, ha. Slainte.

 

[Jameshow]

If the angle is quite steep like 10° then the relief hole might stop the tenon splitting.

However if you limit the angle to 5° and match the wedge to the angle of the mortice angle I think you caint go far wrong. That's what I've done.

Don't over think it.

 

[rogxwhit]

It never occurred to me to measure the angles of any wedges - I've always mapped them directly onto the work with the nature of the wood and a sense of the mechanical keying required in mind.

But I've just done a quick assessment, and guess what - 5° or 6° fits the bill!

No matter if it's a house door or a furniture piece. All about the same.

 

[Jameshow]

I use my dovetail square on the mortices and wedges to give me a matching pair.

 

[Sebb]

How is a hole going to do that? If the tenon root wants to split it'll split anyway beyond the hole. The hole doesn't do anything.

you might be right, I’d been taught to drill holes to stop splitting, I don’t always bother and never had it split either way so maybe there’s no sense in doing it….

 

[Jacob]

The "just for enthusiasts and magazine articles, not to be taken seriously" comment from you is interesting. I notice rogxwhit seems to express somewhat similar sentiment towards driving wedges into a couple of saw kerfs with a relief hole at the bottom of the kerfs to form the wedged M&T. I've come across the preferred method of working you described many times, and in almost every case it's been comments made by those from a predominantly joinery background rather than a furniture background.

The general form illustrated by tibi in the opening post is the form I've used in the vast majority of my work where a wedged M&T was required. In truth, that form always seems to have been the most common approach taken by makers in the various workshops I've worked in over the decades, and I think it reflects the fact that those workshops have been primarily furniture workshops rather than joinery workshops.

Incidentally, I don't think either method is the only 'right' one. Your preferred method is quicker (no additional saw cuts and hole boring required), but maybe somewhat less elegant or pretty, and arguably somewhat less secure. You will possibly come back with a rejoinder that I'm one those prissy enthusiasts of pretty over production, ha, ha. Slainte.

View attachment 146732​

Do decorative wedges by all means!
But they seem to be a modern fashion.
"Fox tail" wedges in blind mortices get referred to in the old books, as a neat but expensive alternative to the normal through M&T.
But through tenons with foxtail wedges hardly a mention and I guess aren't often found in old furniture. Could be wrong! I've never seen them in old joinery
I doubt they'd be structurally stronger, or have any purpose other than decoration.

 

[Fidget]

...I doubt they'd be structurally stronger, or have any purpose other than decoration...

What's wrong with that?

 

[Yojevol]

That relief hole in the pic is a waste of time and doesn't do anything. People are always making silly stuff up these days.

There are various configurations - one is to drive the wedge into a kerf, another is to have the wedges flanking the tenon - in both cases the mortice is splayed. Careful measuring is good - ideally you want the tenon to be gripped most tightly near its shoulders. It can be useful to make the wedges from wood that's harder than the tenon.

I don't think the hole is intended to prevent splitting. It's there to provided a 'hinge' point so that the tenon spreads uniformly thus creating good contact with the mortice wall.
Brian

 

[D_W]

Do decorative wedges by all means!
But they seem to be a modern fashion.
"Fox tail" wedges in blind mortices get referred to in the old books, as a neat but expensive alternative to the normal through M&T.
But through tenons with foxtail wedges hardly a mention and I guess aren't often found in old furniture. Could be wrong! I've never seen them in old joinery
I doubt they'd be structurally stronger, or have any purpose other than decoration.

Nobody wanted to see much endgrain 200 years ago.

Not sure when it became popular in the UK but it seems to have become the thing to have once mortise and tenons became an industrial joint (arts and crafts, etc).

I've seen showing joinery in plenty of barns on the 200 year-old side of things, but that's about it.

Not saying that people shouldn't like it, just that it wasn't considered desirable on fine work - it interrupts lines and sort of discourages a more classical aesthetic.

https://www.andersenandstauffer.com/gallery.php
There wasn't much talk of shooting anything other than edges and really small work, either, and everyone seems to love that now.

 

[niall Y]

How is a hole going to do that? If the tenon root wants to split it'll split anyway beyond the hole. The hole doesn't do anything.

I think I would have to agree, I certainly wouldn't bother with the hole, but I can see how it creates a hinge for the outer part of the tenon, especially if it's quite close to the edge. How far the wedge is hammered in, would ultimately govern whether the wood splits or not

Although Jacob states that wedged tenons of this sort have more to do with furniture magazines , than the past, my old tutor - who was Loughborough trained - had quite a penchant for them, So much so I would guess that they were quite a feature of some of the older Arts and Craft furniture.

 

[rogxwhit]

I don't think the hole is intended to prevent splitting. It's there to provided a 'hinge' point so that the tenon spreads uniformly thus creating good contact with the mortice wall.

If the work was done sensibly, the saw kerfs that provide the wedge room in that picture would be nearer the tenon edges, and there'd be no need for the holes. Why do two jobs when it can be done with one? A good craftsman always pursues economy of means.

 

[rogxwhit]

There are several sensible and economical ways that a through wedged tenon can be done. They are part of the vocabulary of making in wood, whether house doors, furniture or anything else. With a house door they have not always been thought of as being present to be seen, and indeed were commonly painted over, but were part of sound making practice and part of the structure of the door.

In furniture they might be present in rustic work, and were also widely used in arts & crafts furniture where they function in part as a visible demonstration of the maker's intent.

(Above work c1930's by Stanley Webb Davies.)