08-26-2017, 07:29 PM
OK, this is probably one of the first projects for an apprentice and there are many variations, so here's mine.
I’ve not used carriage stops often, probably because I rarely make more than a couple of similar parts at any one time. Mainly I use a travel indicator when it’s necessary to adjust lathe carriage travel distances more precisely than a 6 inch scale. Withdrawing a single-point threading tool at a consistent runout location is one example.
I have an inexpensive H-F magnetic travel indicator holder for my small Emco lathe and it works OK for that machine.
But the larger (Sheldon) lathe configuration can’t accommodate it so I had to make a holder. I wanted the holder to function both as a travel stop and to clamp an indicator, as in this configuration:
Note that there is a stop screw at the top of the holder, with a threaded locking wheel. This is to prevent running the carriage past the indicator limit and ruining it. Although the photo shows a one inch indicator in the holder, a two inch indicator is usually installed.
Configured as a carriage stop:
The limit screw was threaded to 1/4-20 so that every revolution equals .050 inch. It is fairly easy to adjust within .010 by eyeballing the knob. More exacting measurement is needed when precision is required, of course.
Disassembled:
All parts are steel and just for looks, I used my hillbilly coloring process on the two main pieces. This consists of torch heating the parts to a dull red and tossing them into a can of used motor oil.
This leaves a black surface that is slightly harder than the bare metal – it’s close to a black oxide finish. Other than that, I didn’t spend much time making the thing look nicer.
I’ve not used carriage stops often, probably because I rarely make more than a couple of similar parts at any one time. Mainly I use a travel indicator when it’s necessary to adjust lathe carriage travel distances more precisely than a 6 inch scale. Withdrawing a single-point threading tool at a consistent runout location is one example.
I have an inexpensive H-F magnetic travel indicator holder for my small Emco lathe and it works OK for that machine.
But the larger (Sheldon) lathe configuration can’t accommodate it so I had to make a holder. I wanted the holder to function both as a travel stop and to clamp an indicator, as in this configuration:
Note that there is a stop screw at the top of the holder, with a threaded locking wheel. This is to prevent running the carriage past the indicator limit and ruining it. Although the photo shows a one inch indicator in the holder, a two inch indicator is usually installed.
Configured as a carriage stop:
The limit screw was threaded to 1/4-20 so that every revolution equals .050 inch. It is fairly easy to adjust within .010 by eyeballing the knob. More exacting measurement is needed when precision is required, of course.
Disassembled:
All parts are steel and just for looks, I used my hillbilly coloring process on the two main pieces. This consists of torch heating the parts to a dull red and tossing them into a can of used motor oil.
This leaves a black surface that is slightly harder than the bare metal – it’s close to a black oxide finish. Other than that, I didn’t spend much time making the thing look nicer.