Rounding tapered staff

ralpher | Posted in Assign An Expert For Me on March 29, 2010 07:18am

I have a couple of friends who are into the martial arts – they have asked if I can make them staffs – they gave me one to look at – the staff is 6′-0″ long – 1 1/4″ diam @ the center tapered to 7/8″ on both ends – I would not have a problem setting up a jig for my table saw to cut the tapers but I am not sure how to go about rounding the staff since the radius is changing – any advice would be appreciated – Thanks Ralpher

Replies

joinerswork | Mar 31, 2010 08:15am | #1
Ralpher,

Without a lathe, you'll need to round the shaft by hand. I'd knock the corners off the square tapered shaft to make it octagonal in section, then round off the octagonal corners, scrape and sand.

The lines for a tapered octagonal layour can be easily done if you make a simple marking guage like the one in the attached sketch. Make the opening between the "V" ends slightly larger than the square shaft at its thickest area. The points in the bottom of the saddle can be nails driven partly in and clipped off, their ends filed sharp. In use, the guage straddles the shaft, and is dragged along its length, twisting the guage to keep the vee ends tight against opposing sides of the shaft.

The distance between the points, and their location within the saddle can be determined by drawing a square out and laying out the octagonal clipped corners , to get the measurement- it is not a simple division of the space between the vee's into thirds.

Ray
Frank Vucolo | Mar 31, 2010 08:41am | #2
Spokeshave

Hi Ralpher,

After taking it to a taper on our table saw, work it round with a spokeshave, then take a scraper to it, a little sand paper and there you are!

Frank
bigfootnampa | May 12, 2010 05:56pm | #3
Boat builders do this all the time with spars and masts. First step is to taper square and then bevel the corners to get an octagon then taking the remaining 8 corners off you will have a sixteen sided tapered staff. As you can see it is a small step from there to a smoothed taper. I would personally use a surform file for most of the roughing work and follow with increasingly finer grades of sandpaper. Once your square taper is accurately achieved you can easily maintain the proper taper as you cut away the corners by working in steps and watching to get the flats equal in size. DO keep your angles pretty consistent as you cut the corners though or you will lose your equal size reference and drift toward greater inaccuracy.