Tuesday, 21 July 2015

Bedside tables (nightstands) - Part 4 - Completing the legs - a tablesaw tapering jig

The lower 120mm (4-3/4") inside sections of each of the legs were intended to be tapered to give the illusion of lightness to the whole piece. To do this I used my trusty old tablesaw leg tapering jig to clamp each leg in place whilst slightly angled relative to the blade.

Front view

Side View

Jig mounted onto the sliding table
on the table saw
The piece of stock shown in the jig is not
sapele but something of similar section
to show the principle

Tablesaw leg tapering jig

Mine is made from 1/2" plywood with a mahogany runner on the underside to engage the tee slot. As my tablesaw also has a sliding table and these legs are not too long I use some tee nuts and hand nuts to fix the jig to the sliding table. The leg is marked with a line at the angle it needs to be cut. Then the intersection of the line is placed onto the edge of the plywood nearest the blade. This had been previously cut flush with the blade many moons ago.
Registration block end
A scrap of the same thickness as the workpiece
is shown at the bottom of the picture
underneath the bridging clamp.
The underside of the bridging clamp
has some self adhesive sandpaper on it.

Next a registration block, essentially a square scrap with a square corner cut out, is placed at the lower end of the leg. Then the registration block is screwed to the plywood base.
Another location block is placed into position against the back face of the leg and it too screwed to the base. This creates an ideal 3 point contact that makes allowances for discrepancies in the length of the leg but always holds it in the same position relative to the base of the leg.
Location block with clamp
A regular clamp holds the leg in place against the top stop and a bridging clamp holds the bottom end of the leg tight to the face of the table.

The cut is then made on the table saw, the saw stopped, clamps released, leg turned through 90 degrees (the previously cut taper faces upwards), the clamps re-tightened and the second taper cut.
The results are perfectly cut tapers that probably only need a little cleaning up with a handplane to remove the saw marks and bring to the taper to the 120mm alignment line.

I did this on all 8 legs to achieve consistency throughout each leg and batched them out.

This type of jig will work on tables saws with 2 slots and can be made in a short time.

Round over using a router table 

The next job was to run the outer most corner of each leg through a  bearing guided 1/4" radius round-over bit to create a nice round-over. This is best done in a couple of passes, even though the radius is relatively small, on the router table as it is quite easy to tear out at this stage. There would be nothing worse than putting so much work into the legs only for one of them to severely tear out! Also this particular piece of wood was quite difficult to work.
After that was completed the remaining corners of each leg were run over a 1/16" round-over bit to break the corners. The bottom of each of the legs were chamfered with a block plane to minimize tear out when the tables are dragged across a floor in later life.
Finally sanding the legs to 240 grit to prepare for the subsequent sub assembly glue up.

Finished legs and aprons ready for glue-up

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