The picture above shows the 3 steps I will be progressing through today. Start with the glued up blanks, then shape the curve on the bandsaw and router table, then taper the legs using the tapering jig. There are lots of ways to do this, and my ways are not likely the best but they work well for me. your mileage may vary.
The first step is to afix the template to the blank. I use double sided turners tape for this--it holds the pieces together well, but is not impossible to remove after use.
Next it is off to the bandsaw to rough cut the shape of the legs. I use this jig i built to make the process as idiot-resistant as possible (nothing, in my experience is truly idiot-Proof).
The jig acts like a poor mans bearing guided router bit. it allows the stock to pass underneath and keeps the bandsaw blade a constant distance from the template. here is a close up of it in action.
after the stock is roughed out on the bandsaw, i use a bearing guided bit (two, actually) to trim it flush with the template. Marc Spagnuolo, aka The Wood Whisperer, just posted a video on template routing curved table legs. One of the issues he adresses is the tearout that comes with trying to flush trim the 'uphill' portion of the grain on a curved piece of stock. He suggests sanding as close to the line as possible for the uphill sections, but i have found this to be time consuming and that it still yields imperfect results. My method avoids 'uphill' cuts altogether. Here is how i do it:
We will employ TWO bearing guided bits in this process. The first step is to determine which sections of the leg will be 'uphill' cuts when the template is on the BOTTOM of the workpiece. i have marked those 'uphill' sections in the pic below so i can avoid them in the first pass. Note that the bit has the bearing on the bottom, and the workpiece is positioned with the template face down. With the bottom bearing bit and the template facing down, i flush trim the DOWNHILL SECTIONS ONLY and then stop.
After that routing is complete, i switch to a bit with the bearing on the top and make the cuts with the template facing UP. the set up is below--note that the X's are still there, as i left these sections rough in the previous pass. through the miracle of Euclidean Geometry, the formerly uphill sections are now downhill, and are flush trimmed without incident (or unsightly tearout.)
the result of the above operations is a perfectly shaped, tearout-free leg. The final step in construction is to taper the planar faces of the legs. I will use the tapered sled i made earlier. First, I afix the leg to the sled with the top against the cleat. the cleat is on the low side of the sled, so i will be removing stock from the foot of the leg as it passes through the planer.
I mark the face of the leg with chalk and in she goes! (low side first)
here is the result, you can see where the taper ends--there is still chalk remaining on the top of the leg. It took about 5 passes to remove ~5/8 of an inch of stock.
once all 4 legs have had their first face tapered, i install a shim so that the opposite face will rest on the sled as though the first side had never been tapered.
I made this shim from a scrap piece of stock using the tapering sled. I passed it through until one end was about 1/16 thick. once the shim is complete, just rotate it end for end and screw it down. Here is it with a leg taped to it, tapered side down.
Pass the legs through the planer as before and you have all 4 sides tapering neatly from 2x2 at the top of the leg to 3/4 x 3/4 at the bottom.
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