General question(s) about wedged through tenons

[Kevin Smira]

Three minor/quick questions...

1) how much extra tenon length do you plan on for a wedged through tenon? I want my tenon to stick past the mortised pc by 1/8" after all finish work on the tenon is done (trim, chamfer, pillowed, etc).
2) is there a general dimension/angle that you should use when cutting your wedges?
3) I believe I read/saw somewhere that you should have a flat edge and an angled edge. The flat edge should to towards the inside of the tenon, not the outside, correct?

Thanks,
Kevin

[Derek Cohen]

Three minor/quick questions...

1) how much extra tenon length do you plan on for a wedged through tenon? I want my tenon to stick past the mortised pc by 1/8" after all finish work on the tenon is done (trim, chamfer, pillowed, etc).

I generally provide an extra 1/8" for trimming.

2) is there a general dimension/angle that you should use when cutting your wedges?

That is up to you. It is largely aesthetic, that is, as long as you have "some" angle (and it can be very small), you determine what will look best to you.

3) I believe I read/saw somewhere that you should have a flat edge and an angled edge. The flat edge should to towards the inside of the tenon, not the outside, correct?

I have not fussed about this - just created a wedge, glued it, and wacked it in. Never had a problem. A wedge is a wedge. The angled rear is going to be trimmed off. Orienting the wedge and grain is much more important.

Thanks,
Kevin

Regards from Perth

Derek

[Kevin Smira]

Many thanks Derek.

Follow up question...

Is the mortise made slightly oversized in order to allow the wedge to do the “locking” function?

Kevin

[Derek Cohen]

Hi Kevin

The mortise is tapered at each side once it is completed. As with the wedge, the amount of taper needs only be slight. It does not require much taper to lock the tenon.

http://s3.amazonaws.com/finewoodworking.s3.tauntoncloud.com/app/uploads/0000/01/05160018/011124066-main.jpg

Regards from Perth

Derek

[Brian Holcombe]

If this is for a door you can make one side flat (normal tenon) and the other side flared for the wedge. Be forewarned wedge tenons can be a high maintenance joint, they're best used in scenarios where the wedge can be retightened if need be, or glued like a normal M&T. The issue I take with wedged tenons is that the joint will often shrink away from the shoulder making a minor gap at times of low humidity. This can be unsightly.

If you have the option to draw-bore and peg, do so, as it is a better option in terms of holding power.

[Kevin Smira]

Thanks Derek and Brian. This will be on a bench for the bedroom. The “legs” will be double wedged through tenons and the stretcher on the bottom will be a single wedged mortise and tenon.