mitred/scribed ???

[paulfoel]

Sorry for being dull but whats the difference?

Does this apply to fitting dado rails ???? Please explain.....:-)

[Stuart Noble]

[Weatherlawyer]

There are three occasions for scribing or mitring a joint in a board. It depends on whether the joint occurs on a straight run, an outside angle or an internal one. You mitre a straight run and an external corner.

When you mitre a dado or skirting board you are creating a butting joint that depends on the wall being perfectly square and so firm that it will not give the slightest as the boarding is fitted.

When you mitre an outside corner the two pieces to be joined are going to be banged together during fixing.

Doing that to an internal angle, the joint will open -it will be forced open. Also, over time the joint will open as the material expands and contracts. You will be very disappointed with the effect that that produces.

With a scribed joint the two boards are again abutted but through the complete thickness of the scribed board. Any shrinkage will seem minimised and any gaps in the joint that appears will fill very easily with paint or filler.

You mitre straight runs in boards because with such a mitre, any movement will be minimal. The surfaces mitred are large and can be nailed fairly easily.

You glue and nail them having cut the join over a stud. Since you can fix them to the stud, movement will be almost zero.

The alternative there is to chop the board straight through at 90 degrees. If you do that, any movement in the boards will show up as a gap in each joint.