Router Sled

This is a simple jig for "planing" and thicknessing timber by running the router over the whole surface (with shims underneath when doing the first side if required). I made it out of a length of 40 mm × 40 mm × 4 mm aluminium extrusion I had lying around, along with some UHMW tape. It currently runs on some T-slot extrusion that came out of a skip.

This shows the construction of the part of the sled on which the router runs. The T-slot extrusion cross-piece (and thin strip of aluminium that is screwed to it) is removable and allows the sled to operate at different heights depending on the material it is being used with. A single M5 cap screw holds the height extension on so it is very quick to add or remove it.

It isn't obvious in the photos, but four of the screws holding the angle together are slightly longer than the others. They protrude ever so slightly into the track that the router runs on and are conveniently in the right place such that the router hits them and stops sliding along the track just before the cutter hits the extrusion.

This photo shows the rails on which the router sled runs. They are simply bits of T-slot extrusion with some 20 mm mild steel pieces screwed into them using the T-slot extrusion T-nuts. They drop into the holes on the bench and the rails are then guaranteed parallel, which ensures the router sled runs smoothly.

With these rails and the sled, I can "machine" the top of a piece of wood up to 350 mm wide and up to about 1.1 m long.

This shows the sled half-way through planing a piece of (just under 30 mm thick) oak. It was already relatively flat on the other side so didn't need shims to stop it rocking. It is held down with hot-melt glue.

These photos show what it looks like after completing the planing operation.

The router leaves some light lines in the surface of the wood, but these are easily cleaned up with light sanding or a quick pass with a lightly-set hand plane.