I managed to build this lathe in about a week, with not much more than a cordless drill, a drill press, a jigsaw, and assorted hand tools. I hope that I have documented my project here in an understandable way.
Warning: This is a powerful device designed to spin stuff quickly. I take no responsibility for anything you do. Don't try this unless you have at least a little bit of experience with tools. And wear safety glasses when using it because particles fly around.
Step 1: Decisions
The first thing you have to decide is what kind of lathe you want. Either to work with metal or wood. A wood lathe requires a less powerful motor and not as close tolerances. Also a wood lathe does not need the complicated tool rest that a metal lathe has. For the first version of my lathe, I decided to just stick with wood and see if I could come up with something that actually worked.
The next thing to decide is size. I would highly recommend not going too overboard... tree size logs on a wood lathe and 50 pound steel bars on a metal lathe are best left to professionals I think. I decided to try to make a wood lathe for pieces up to 4 inches in diameter and about 30 inches long, although I will not be trying something that big until I get more practice with small items, like tops, chess pieces, other little toys. But I figured that I had a pretty powerful motor sitting around, so I might as well make it big enough to handle large salt shakers and chair legs so in the future I could do large things.
Step 2: The Bed
The bed needs to be very solid and not flexible or the material will wiggle all over as you are trying to work with it. I had an 8 foot long piece of 1/8" thick aluminum angle, 1.5" x 1.5". Out of the 96", I cut two 40" pieces for the main rails. This design turned out to be slightly more wiggly than I had hoped, maybe for the second version I will use steel.
The picture shows the two pieces on a stool in the orientation they will be in.
Step 3: Bed Construction
I numbered each intersection of the base in case I ever need to take it apart, it would be easier to put back together.
The first picture is a close-up of one of the two UHMW pieces on the end. The second photo shows the bed being stood up by a clamp.
Step 4: Feet
The first photo is a close-up of one end. The second photo is the whole bed standing up by itself!
Step 5: Mounting the Bed
The first photo is a picture of the bed mounted on top of my workbench. The second photo is a closeup of the feet mounted to the wood.
Step 6: Tailstock Slide Pieces
The photo shows the pieces assembled, which is covered in the next step, but I did not want to take it apart again for a photo.
Step 7: Tailstock Base Assembly
I drilled 4 holes into the top of the UHMW, all lined up very precisely with the gap between the rails. The one on each end are 3/8" diameter, to allow a bolt to accurately travel through the gap between the rails with a nut underneath for clamping the tailstock down to the bed.
The first picture shows it on the end of the lathe to show how it should fit the track upon completion. The second picture shows it right after assembly. The last photo shows your monorail in action!
Step 8: Headstock Basics
I made two of the supports. The height of the main shaft above the bed determines the diameter of work that can be done on the lathe, so i added more UHMW pieces beneath the shaft supports to raise the height of the actual supports. (whew lots of supports, but just look at the second picture in this step). I then tightened the nuts on the bottom fairly tight to secure the two supports about 7 inches apart.
The first picture shows one of the completed supports. The second picture shows the supports mounted to the bed of the lathe.
Step 9: Headstock Alignment
The photo shows the shaft pretty well aligned with the bed.
Step 10: Securing the Shaft
Step 11: Mounting the Motor
I secured a large aluminum plate to one of the shaft supports and mounted the motor to the plate. Before mounting the motor, you should take into consideration the length of the belt you will use to transfer the power. When the motor is mounted, the shaft of the motor and the main lathe shaft should be parallel. An alternative would be to mount the motor to the 2"x4" base, which would take the weight of the motor off of the lathe bed.
The picture shows the motor mounted.
Step 12: Power Transmission
The gray colored iron pulley on the motor I had kicking around, but I needed a pulley for the lathe shaft. I made one by cutting three circles out of MDF and gluing them together. I found these pretty awesome pieces at Home Depot called tee nuts (see third picture). These are basically threaded inserts for wood, so I imbedded one of these into the center of the pulley. Once I had the two pulleys properly aligned, I tightened the setscrew on the iron pulley to secure it. Because of the tee nut, the wooden pulley acts like a nut, so to secure it in position, I simply tightened another nut against it.
The first two pictures are two views of the completed belt drive. The third picture is a tee nut.
Step 13: Chuck Construction
The basic idea of the chuck is to hold the work. I chose to make a 4 jaw chuck because I can hold square things as well as round things. I started by cutting a 5" circle out of some thick MDF to the best of my ability with a jigsaw and then drilled a hole in the middle. I fitted the hole in the middle with a tee nut. Using the same method as the pulley, I threaded this piece onto the shaft and secured it with a nut. Using a very steady file and a moderate speed, I smoothed out the edge of the disc to make it uniform. By holding a pencil up to the disc, you can draw circles on the disc, so I made one near the outside edge.
Next I drilled and tapped carefully lined up holes in aluminum angle. I secured the four pieces of angle evenly spaced around the circle I drew. Through the other hole in each piece of angle, I put a screw. Look at the first photo to see the completed chuck. Basically a piece of wood can be secured in the center of the four jaws by uniformly tightening the four screw, kind of like a Christmas tree stand.
The first picture shows the finished chuck. The second picture shows a side view to show how the shaft needs to end inside the chuck. The third view shows the mounted chuck from an angle.
Step 14: Headstock Testing
The photo shows the completed headstock.
Step 15: Tailstock Finishing
I tightened the tailstock down so it was just barely movable, but not wiggly. By pushing the tailstock against the headstock while the empty shaft is spinning, I made an imprint of exactly where the hole should be drilled so it lines up with the headstock shaft. Then I used the drill press to drill the hole precisely, but accidently drilled the holes 5/8" instead of 1/2" so I fitted some bronze bushings into the holes to reduce the diameter. Double check that the main lathe shaft is correctly lined up with the new holes, and then reattach the chuck to the shaft.
The picture shows the completed tailstock.
Step 16: Tailstock Accessories
I had a broken cordless drill kicking around, so I took it apart to see if I could get the chuck out of it. Lucky for me, it had a 1/2" diameter shaft too, so I now have a chuck to hold drill bits and accessories in.
The first photo is of the dead center in the tailstock. The second photo is the cordless drill chuck in the tailstock.
Step 17: First Tests
After a few tops, I tried to make a chess king, but after the crown broke off, it became a queen. I made this in a similar way; supporting both ends of the piece until the rough shaping was completed, then sanding.
The first picture shows the wood blank ready to go. The second picture shows the queen being carved. The third picture shows the remains after the queen is done. The last picture is 3 of the 4 tops and the chess queen (my dog ate one of the tops).
Step 18: Conclusion
Most of the design specifications were met. Because the headstock and tailstock are bigger than I originally planned, there is only about 24 inches between the chuck and the center, but that is still a respectable length. I can turn the pieces of aluminum angle around on the chuck to be able to handle up to around 4 inch diameter blanks.
If I make a second version, I would use a thicker main shaft because the 3/8" rod can flex a little bit. I would extend the bed at least another foot, so that I could do table legs. For tops and chess pieces, I have not found the need for a tool rest, however, I imagine it would be helpful when turning larger pieces, so version 2 would incorporate a tool rest.
Step 19: Lathe Tools
Step 20: Further Turning
The first is a very small cup with a captive ring, meaning that the cup is one piece and the ring was cut from the middle of the stem of the cup. About 3" tall.
The second picture is a much longer thing (12") I made to test turning long items; it is basically a bar with 4 captive rings. Captive rings really freak people out when they realize the rings don't come off.