To answer the questions:
1. The seat just is a cross piece with a cleat in the middle between the rails, so it slides and can be configured to your contour. I just took a couple of pieces of drop from the assembly to make this one, but may sculpt it a bit as I see the need. (The plans have a foam insert and fancy padded seat, but it is still sliding and removable).
2. As for the style, I was torn because I am not sure where this is going to lead, so I liked this design in that I could easily adapt the head and support to meet future needs. The support surface is just screwed on, so is easily modified, and the clamp crosspiece in the jaws is also just held by a bolt, so it also can be shaped for need. The limitation is width, but right now I do not see that as a problem. If it becomes one it can be easily rectified by adding spacers and threaded rods to hold the clamp arms.
3. Travis, yes it was pretty simple. The hardest part for me was drilling the holes exact and aligned with my drill press. (if I would have had some 8" long bits it would have been a piece of cake). In retrospect, I would probably use my brace and an auger bit with all the pieces clamped together for the long bolt and dowel holes. Hand tools do have some advantages.
4. As for what I plan to do with it: First are some hiking staffs/walking sticks as I have some nice woods back of the house, and have BIL and nephews that are into the outdoors. 2nd is handles for a few chopping and other tools. As I get older and my finger joints less forgiving, I find egg-oval sculpted handles make some tools more friendly. Other projects in the works/lineup are a table for LOML, and possibly some chairs, so hand shaping the leg curve round-overs and chair slats and possibly attempts at carving some details are other uses I envision.
I built a workbench a while back, but it lacks a good method of holding a piece for drawknife/spokeshave work. Hopefully this will meet that need. For about $20 materials (not counting the walnut I used for the ratchet which was spit ends off 8/4 rough cut and a bit of 3/4 plywood drop) I feel free to experiment with it without any regrets. I admit it is a work in progress (as the lack of finish suggests), but hopefully not a wasted week-end.
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