You saw a quick shot of the spindle in an earlier post. Let’s take a closer look.
The spindle rides on 3 bearings. Two are ball bearings that sit in the walnut bearing blocks. The third bearing is a thrust bearing at the leftmost end. The thrust bearing offers a low friction way to absorb lateral pressure. The race that absorbs the pressure has a center hole too small for the spindle to pass through. The bearing ring in the middle is a very tight fit on the end of the shaft. The outer race has the same fit as the ball bearing. A photo details the parts for folks who haven’t seen this sort of thrust bearing.
OK. What are we going to use for a drive pulley? There aren’t a whole lot of commonly available things of a decent diameter already having a 5/8″ hole bored through them. Hey, I could make one on a lathe! But, what to use to drive the lathe to make a drive pulley? Wander the aisles of the home center, asking “what about this, that, the other thing over there?”
Found it! A finial for a fence post looks like just the thing. Cut off the ball part. Bore a hole through it.
Fix it to the spindle, and get going. …and only $3.42. With all the boring I’ve done with the brace and Russel Jennings augers, I’ve gotten fairly good at putting holes near where I want them. Finding the center of a not-so-round pressure treated ball, and then drilling dead on the center was a near impossibility, and I lived up to that expectation. It’s not perfect. Yes Jeremy, it does wobble a bit, but it’s not headed for 70mph. Fixing it to the spindle is done with a couple of 1/8″ holes driven into the ball and partly into the spindle and #8 by 1-1/2″ wood screws. Crude but practical for a very temporary drive pulley.
looking good.what’s the time on this build.
The 2″ wide belt would fit very snugly over that, cupping to match the shape, wouldn’t it? How incredibly clever. And with the added width of the belt for friction, you don’t have to create a figure-8 pattern a la Roy Underhill’s treadle lathe drive cord.
Thanks for detailing your progress on this. I’m a spring pole lathe user myself, but I’ll admit that the constant drive of a treadle lathe attracts me.
rootertooter,
Time? I don’t track time unless I’m billing for it.
Mark,
Right on! The ball shape is perhaps too pronounced, but it does exactly as you surmise. The permanent part will also have a crested / barrel shape for the same effect.
Besides, it’s real hard to make a figure 8 with a belt. 😉
Do you post pics of your spring pole, or the work you do on it? Would love to see them.