OK, so it is not quite in super 3-D, especially since I forgot to take any pictures on day 3. Maybe it should be 4-D since I took some pictures later in time. Hmm. But that doesn’t really work with the third installment of the class report.
We did a lot of turning saw work today along with some chisel work. I wished I brought my Auriou rasps instead of my bench chisels because we did a lot of shaping work and my use of the turning saw resulted in some rather …ahem…interesting ogees. On both the upright and tailstock, we had some shaping to do with the saws.
“All right Mr. DeMille, I’m ready for my close-up,” Are you sure you’re ready? I need some practice with the turning saw and the ogee embellishment (at least I think they are ogees) certainly shows that, even after some rasp work. We added these to the treadle arm upright and the headstock upright on this day.
The lathe itself is designed to be knocked down for easy travel, and on the original design, it used tusk tenons and wedges to hold the bed rails and stretcher to the uprights. We improved on this, instead cutting a sloped mortise and a sloped notch on the underside of the rails and stretchers, then using a wedge at the top. It basically is a dovetail with one half of the tail being the wedge. Based on a test mortise and wedge that Roy cut, we used a 1/4″ height on the triangle over the 1 1/2″ thickness of the uprights. If you extend that out to 6″, you get a 1:6 ratio between rise:run. Sound familiar? For the wedges, we actually used a 6 inch length and 1 inch thickness.
Here you can see the gap at the top of the mortise where the wedge will fit, along with some layout lines, the most prominent of which is where the upper portion of the mortise was originally. I haven’t bothered to finish plane the lathe yet, and maybe never will. It is a tool after all. Also note that the tenons are only on one side. For the bed ways they face the outside of the lathe. The lower stretcher just had to be consistent from end-to-end.
And a side view of the bed way/rail with the notch in the tenon. Not a very big notch, but it makes a huge difference in how tight the structure becomes with the wedges.
And a view of the lower stretcher mortise showing (I hope) the slope of the mortise. When the wedges were pounded in, this thing became like a small tank. There was no moving the structure without moving the *entire* structure. I think if I make a knock-down bench, I’ll use this system because even after using it for a couple days, I only had to tap in the wedges to tighten it up once or twice, and that was early on.
We also fitted the tailstock to the bed. We first had to dimension the stock using our bench planes, and mine just had a little bit of cup, but was pretty good overall–it was just one big hunk of stuff. Fitting the tailstock was fairly simple–take the stock, mark the width and depth of a ‘tenon’ to fit between the bed rails, and make sure you have enough excess to fit a mortise. I grabbed a frame saw and managed to forget that the saw needs to pushed at a slight angle, because when I was cutting this tenon, the saw filled the room with a horrible racket. Sorry guys. It was seriously annoying, even for me.
And while this video shows Roy using his custom dovetail saw, I am pretty sure it was shot on our third day. In the right background you can see Chuck using a big frame saw for shaping the tailstock (at least I think that is what he is doing, tough to tell), and JT across the way looks to be chopping the slope on the mortises.