The Corner Bridle Joint!!
The tools you will need are:-
1. Tenon Saw
2. Mortise Gauge
3. Try Square
4. Sharp Bevel Edge Chisel
6. Drill and drill bit.
7. Ruler/Tape Measure
8. Bench Vice or Workmate
9. Bench Hook
For the bridle joint, one of the pieces to be joined needs a tenon and the mating piece needs a groove.
To make this simpler to explain ‘A’ will be the piece with the groove & ‘B’ will be the tenon piece!
Take piece ‘B’ and lay it flat on your workbench/workmate. Then take piece ‘A’ and lay it on piece ‘B’ as shown in the photo to your left – making sure the side of piece ‘A’ is flush with the end of piece ‘B’. (ie at right angles to each other)
With a pencil, mark the width of the timber onto piece ‘B’ using the mating piece ‘A’ as a guide.
Using a try square and pencil, follow the line all the way around.
Do this and the step above on the mating piece (‘A’).
Using a ruler, you now want to set the mortise gauge.
When doing mortise and tenon, the general rule is to make the width 1/3 of the thickness of the wood. The same applies to the bridle joint.
With your mortise gauge, gouge lines on both edges from the shoulder line to the end of the wood. Also gouge a line on the top of the piece (the end grain) – Do this on both ‘A’ & ‘B’……
As I’ve said before "A good tip so you don’t go past the line is to put a small indentation just before the line, using your mortise gauge – so when you gouge the line, the pin on the marking gauge should fall into it, therefore stopping you going too far" and "When using the marking gauge it’s best to hold it at a slight angle and to take several light passes. By doing this you should be left with a nice straight gouge line".
Once both pieces have been gouged mark out the waste sides! (left ->) Remember piece ‘A’ will have the groove and piece ‘B’ will be the tenon.
To make it easier, on piece ‘A’ in the centre above the shoulder line drill a hole all the way through the wood.
I’ve used a forstner bit which is 1mm smaller then the width of the tenon & groove.
It’s now time to cut down to the shoulder lines on both pieces, remember to cut on the waste side of the gouge lines.
Clamp one of the pieces into your vice or workmate at about a 45° angle, with the end facing away from you. With a tenon saw, saw down the waste side of each gouge line keeping the saw parallel with your bench/workmate (fig1). Making sure you don’t go past the shoulder line.
Unclamp the work piece and turn it around so the edge faces you and continue cutting down the gouge lines (fig2). Then place the piece upright in the vice/workmate and saw down to the shoulder line (fig3).
With a sharp bevel edge chisel square up the round edge left by the drill hole on piece ‘A.’
Using a bench hook and tenon saw, cut along the shoulder line on piece ‘B’, on both sides to remove the waste pieces.
Test the fit of the pieces. They should fit fine but if the tenon’s a bit tight, clean it up with a bevel edge chisel.
There you have it! A very strong and nice looking joint.