Thursday, April 2, 2015

There Is A Season, Turn, Turn, Turn

I have my little hobby lathe that I use to make small projects like pens, knobs and other lightweight things. I've always wanted a larger machine for bowls, table legs and larger projects. So here goes, another moderately large build. The plans come from a book of homebuilt tools that I bought some time ago. The entire thing shouldn't cost me much more than a hundred bucks. The majority is built from one sheet of plywood, one sheet of particle board and a few lengths of hardwood. I went to the metal supply last week and picked up a length of one inch round cold rolled steel. I lopped off a hunk of it and centered it up in the four jaw chuck. This is new territory for me. I have never attempted to cut threads on a lathe. I watched a few You Tube videos and figured, "I can do that." After setting up the change gears, dialing in the tool bit location and setting the compound angle I hit the feed handle and made a light, scratch cut. It looked good, a quick measurement showed that I had the correct eight threads per inch that I wanted. After a dozen, or so, passes I had a nice set of threads. They aren't real smooth where the tool cut. I suspect by bit was not sharp enough, but they are concentric and the chucks and face plates fit very nice. No slop or excessive tightness. I'm pleased. The next problem involved drilling a 3/8 hole all the way through the new spindle. It is a bit more than a foot long. I checked around for extra long bits and found the too expensive for the Po' Boy. I have a 7/16 X 12 inch bit. After looking at the plans, I figured that would work just fine. I drilled as far as I could with the long bit. Before I took the piece out to finish drilling from the other end, I had to address another, potential problem. The threaded end needs a number two Morse taper to accept various tapered accessories. I don't have a boring bar small enough to cut inside of a 7/16 hole. As I went through all of the tooling that I have, fate smiled down on me. I have a number two Morse taper reamer. I drilled out the first three inches of the spindle to 9/16 and reamed the hole until I reached the desired depth. The whole tapering process took about five minutes. It was just a matter of  removing the spindle, turning it end for end, re centering it in the chuck with a dial indicator and finish drilling the through hole. I also had to make the tailstock spindle. It was, pretty much, a repeat of the first, except it has six inches of threads. Same taper, same through hole. I'll pick up a sheet of plywood, later this week or next, and begin the main body of the machine

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