Thread: Way to cut/mill T&G floorboards into Shiplap

You dont have to lose any width if you leave the tongue and groove on. The shiplap effect is created by moulding back the face shoulder of the tongue to the required width of the exposed face of the lap and no deeper than the top face of the tongue. Easiest way is through a spindle moulder with a power feeder attached. A one pass operation. A router table can also do the job but will require multiple passes.

Not something I have done but if you look at it you will loose coverage. T&G is in thirds while shiplap is halves of board thickness. Cut off the tongue and groove so that much lost then cut the half laps and you loose more. Cant say how much exactly but recut 2 bits of board for the overlap you want to get an answer.
Regards
John

Originally Posted by rustynail

You dont have to lose any width if you leave the tongue and groove on. The shiplap effect is created by moulding back the face shoulder of the tongue to the required width of the exposed face of the lap and no deeper than the top face of the tongue. Easiest way is through a spindle moulder with a power feeder attached. A one pass operation. A router table can also do the job but will require multiple passes.

Rusty's method will give you the same coverage as the original T&G. This picture might explain it easier:

Shiplap.jpg

But there are many shiplap profiles and your final choice will be influenced by aesthetics and available router/molder cutters. As John says, some profiles will reduce your coverage .... by the amount of the increase in the overlap. Google "shiplap profiles" for ideas.

Primary reason I suppose is to convert t&G flooring into ext cladding. So ability to cope with movement and lap protecting joins from the elements is more important than aesthetics