Through Wedged Mortise / Tenon....HELP!

[Warren Allen]

Hi,

I have been looking for some good clear instruction how to make a through mortise and tenon joint with hand tools. Most of the books I have like FWW Techniques etc have it sorta mixed in with a plethora of other joints. The step by step I'm finding, to me, takes that "stick figure to Mona Lisa in 3 steps" approach and I'm not easily figuring a plan of attack.

So far I understand the following and my "experiments" have been based so far. My project is @3/4" walnut.

Make the mortise first.

On wedge side make 1/8" larger on the 2 sides to accept the wedge.

1/8" shoulder on tenon

Now with the said @3/4" stock I end up with a tenon 1/2" square and a mortise 1/2" x 3/4".

I've gotten pretty good at making perfectly square holes with just chisels. But amabout to embark on making the tapered mortise.

Anyway lot's of thought and each time I start I make a new discovery. So any definitive articles or book on the subject or pointers gladly welcomed.

Thanks,

Warren Allen
Oceanside, CA

[Bob Smalser]

Hi,

My project is @3/4" walnut.



Here's an easier way to do it:

http://www.sawmillcreek.org/showthread.php?t=11903&highlight=arbor

And here's an easier and more forgiving wedge for thin stock....the wedges you describe are used in traditional door joints with much deeper through mortises:

http://pic20.picturetrail.com/VOL12/1104763/2594265/236027113.jpg

Regardless of how badly the tenon fits, the diagonal wedge fixes it. No need to taper anything.

[Mike K Wenzloff]

Hi Warren,

I make the through mortise as perfectly rectangular [or square if needed] as I can.

Then on the outside where the tenon sticks out, I either eyeball or mark about 1/8" or more depending on the size of the tenon on the top/bottom and pare down at an angle, aiming to end the pared angle about 1/2 or 2/3 of the way to the other side.

Light paring cuts, sharp chisel. Depending on the width, just a few paring cuts to shape, another one or two to clean to the marks which delineate the extent of the mortises show side.

That's it.

Take care, Mike

[Brad Woods]

Warren,

I have read quite a bit about wedged joints recently, though I can't remember exactly where. It was wither in Popular Woodworking, or more likely in a back issue of Wooworking Magazine. The article(s) was by Chris Schwartz. He goes through them step by step, including the various ways of doing them and the best technique that he found. There are many here who are equaly knowledgeable. I've never done them so won't pretend to be able to offer any advice. The Woodworking articles are very good though. Check it out.

Brad

[Michael Hammers]

I have been having difficluties finding any info on hand tooling a large tusk tenon for my workbench base. Bob Smalser's link only shows about half the pics for me for whatever reason. I am interested in hearing from others who have done a large joint like this also.

[Jeff Craven]

I don't have any other experience with mortise & tenon's, but I cut this one with the same size opening at both ends of the mortise & the inside was a little undercut, so the tenon would slide in easily.

http://img259.imageshack.us/img259/5516/toolbox1jh7.jpg

[Mike K Wenzloff]

Hi Michael,

It'll be a while before I get back to the computer and so I suspect you'll get other responses...but in the meantime, how will you be using the tusk tenon? With the tenon vertical and the tusk running down its width, or like tradition Norse where the tenon is horizontal and the tusk going through its thickness?

The former is more difficult, the latter easier because of less distance to taper the tenon.

The mortise, which runs through the end of the tenon, is actually done the same as the mortise for the wedged tenon, except the taper runs all the way through.

In any case, there needs to be both sufficient width beside the mortise in the tenon and at the end else you blow the joint out.

Another general idea is the amount of taper on the wedge and mortise must be darn near identical. So I make a template of the mortise in the tenon in order to lay out the wedge. With a thin piece of ply for the template. That way I can fine tune the taper on the ply to fit the tusk's mortise and actually see it. On large enough tusk mortises, I use a sliding bevel gauge, and with your project one would probably fit in the mortise to determine what angle the wedge needs to be.

Take care, Mike

[Bob Smalser]

I have been having difficluties finding any info on hand tooling a large tusk tenon for my workbench base. Bob Smalser's link only shows about half the pics for me for whatever reason.

Not sure why you want a knock-down joint for a heavy bench, but there's really not much to it.

Here an optional lap joint for a stronger joint:

http://pic20.picturetrail.com/VOL12/1104763/4775424/60398418.jpg

Cut the mortises to fit the tenons...or vice versa if you like...here I'm doing both at once:

http://pic20.picturetrail.com/VOL12/1104763/4775424/60398412.jpg

Cut the mortise for the tusk and reinforce the tenon end so it doesn't split:

http://pic20.picturetrail.com/VOL12/1104763/4775424/60398627.jpg

Fit the tusk and assemble the piece:

http://pic20.picturetrail.com/VOL12/1104763/4775424/60398643.jpg

http://pic20.picturetrail.com/VOL12/1104763/4775424/236059200.jpg

[Don Boys]

Warren,

Rob Cosman has a dvd that shows how to do a wedged tenon. He does the wedge differently than does Chris Schwarz in that then wedge is longer and the saw cut to hold the wedge is angled towards the outside of the tenon.

Don Boys

[Warren Allen]

Thanks all,

I am getting good at chiseling square holes. Not so good at fitting the tenon. I even cheated a bit and rough shaped the last try with a router. So I had a perfectly square tenon about 1/16" over sized. Now with that little 1/2" square peg it was difficult to pare down to a perfect square.

i tried chisels and my large LN shoulder plane which actually gave better results than the chisels once I set up guides, but it still rolled enough to make a poor fit.

Still trying...if this pace keeps up I may try cutting dovetails instead!<G>

Warren

[James Mittlefehldt]

Pssssssst Warren, dovetails are actually easier to do than hand cutting mortise and tenon joints, believe it or not. It is just that they are often so much more visible than mortise and tenons.

[Warren Allen]

Pssssssst Warren, dovetails are actually easier to do than hand cutting mortise and tenon joints, believe it or not. It is just that they are often so much more visible than mortise and tenons.


Hahaha,

I believe you. Took me 3 tries to get DT's I was impressed with and felt I was "getting it".

While I'm close on the M&T I'm stalled, at a loss on how to improve.

I think I'm going to go with a wider tenon that will allow me to use a shoulder plane more accuratly. Getting down within .0001-.0005" on the small "peg" of a tenon I have left and trimming that square is beyond my skills right now.

I ordered Rob Cosmans DVD on hand cut M&T and hopefully that will help.

Thanks,

Warren

[Brad Woods]

Warren,

If it is getting the tennons to fit that is the problem, a tenon router (http://www.sawmillcreek.org/showthread.php?t=36807) may help.
You can also do it with an equally dimensioned piece of wood and a Stanley 71 or Veritas router plane.

Brad