A conventional cross slide will be even easier to work with. If you need too, build a "Romig"
type bed and cross slide, or for a faster and easier job, buy a cross slide table from ENCO for $69
to $130. If you already have a drill press cross feed vise, perhaps you could lap (use an abrasive
paste to gently grind together) the parts together to get a smoother and tighter fit. It may not be
rigid enough for machining steel but it may work well on aluminum alloy. If things go wrong,
just remelt the aluminum and do it again!
How to build a heavier duty "temporary" lathe
(1) Disassemble a junked engine that came from a manual shift car or truck, remove pistons and
rods but leave the crank and flywheel in place. Check the main bearing clearances and add shims
to fix any excess play. Remember not to block the oil holes that you need to drill in the main
bearing caps. Lubricate with oil through these holes or drill or tap for grease fittings. Drill and
tap holes in flywheel for "old time" faceplate clamps (page 11). If you later get a 3 or 4 jaw
chuck, then machine the mating grooves in the flywheel/faceplate and just bolt it on. If the only
engines blocks you can find have thin automatic transmission type flywheels, you may still be
able to machine aluminum or drill holes in steel. Just work gently on the aluminum and make an
adapter for a drill chuck that will bolt to the end of the crankshaft. Be on the lookout for a regular
flywheel and replace the automatic transmission flywheel if you want to use the machine for
heavier work .
(2) Cut one or two (depending on frame width) 4' to 7' long straight pieces of truck frame (or a
piece of eight inch wide channel iron) and use the head gasket as a hole guide so that the rail
pieces/channel iron can be bolted to the head surface.
(3) Turn block with the bolted on frame pieces upside down so that at least two feet of
protruding frame section can be used as a lathe bed.
(4) Bolt on the Romig steel and cement bed or what ever you use for a cross slide, so that top is
about 2 or 3 inches below the center of the flywheel. The bed should be offset and located as
close to the left edge of the flywheel as possible. Before you permanently attach the cross slide,
mount a lathe tool holder and be sure the cutting tool can cut from the center of the flywheel to
the outer edge.
(5) Running the lathe with a simple motor and crankshaft mounted pulley arrangement may
result in too high a spindle (crankshaft) speed. One way to slow the spindle down is by using the
built in reduction of the ring and pinion gears. Gut and cut the starter motor frame (shown below)
to convert to flat belt drive and use a timing belt pulley on the motor end. Make a set of
aluminum alloy pulleys to get other speeds once the lathe is running.
(6) Use frame parts or angle iron and threaded rod to build an electric motor, bicycle drive or
small gasoline engine motor mount. Don't forget that the drive pulleys have to line up so that the
bolts that hold the starter together don't interfere with the flat belt. The belt could be a cut to size
and glued together serpentine or timing belt.