Joining the newel to the stringer

With the shoulder line determined we can go about marking and cutting the tenons on to the stringers and morticing the newels ready to accept the stringer tenons.

Stringer and newel Mortice and tenon position.
Stringer and newel Mortice and tenon position.

The closed stringer tenon.

The tenon position is fairly straight forward, once you have the shoulder line determined the tenon can be formed onto the end of the stringer, the only real thing to be aware of, is that the tenon is set in the solid timber and does not encrouch into the tread and riser rebates. This will avoid having a tenon with a tread rebate going through it and weakening the tenon.

Make sure the the tread side of the tenon does not cross over line A-A and into the rebate area.

Tenon depth from stringer face
stair stringer Tenon depth

Aligning the stringer and newel post.

Closed string alignment.

To position the newel mortice you will need to know where the spindles sit in relation to the stringer, when the stairs are of closed string construction this is straight forward. The centre line of spindle and the stringer will align with the centre line of the newel post. Therefore you can set the mortice with the same amount of offset if any as there is tenon offset on the stringer.

Newel closed string spindle align.
Newel closed string spindle align.

Still working on this page.

Cut string Alignment.

When aligning the cut string one has to be aware of the alignment between the handrail centre line and the stringer centre line, These two are connected by the type of handrail support whether it be metal, timber, glass or any other type of connection. The handrail will sit centrally with the newel post and any offset between the handrail centre line and stringer centre line must be used when setting the stringer to newel position. In this example we will use a traditional spindle set up, where the spindle is set with its well side face in alignment with the stringer face and the handrail centre line in alignment with the spindle centre line.

Handrail, spindle, stringer alignment.

In this example you can see the handrail and spindle centre lines are set directly over each other however the stringer centre line is offset to one side.