Lathe – repetitive work using stops
Though using a capstan is the obvious way to make many parts of the same design there is another way of doing this just using stops on the lathe. The idea is that if the lathe has stops in both the in/out and left/right directions each pair of stops defines a part of the workpiece to be removed.. It is assumed in all of this that the stops are marked and are rotated together.
fig left/right stops
fig in/out stops
With two sets of stops like this it is possible to make quite complicated shapes. It is still possible to have one or more tools held in the tailstock.
If the tool in the toolpost has to be changed it will be found that some stops will have to be of very different lengths. However it is quite easy to use any ordinary tool to be used as a set to length stop.
In this example the work is done in a series of steps. For each step there are one or two stops in use. At any time other actions using the tailstop can happen. These could include center drilling, drilling and tapping. It is also possible to cut a thread using a die in the tailholder.
In all these cases the current step is the letter on the top of the stop though the actual stop position is somewhere else.
The first step is to set the workpiece to length.
The left/right stop sets the position of the cutter. For the first piece the cutter might cut right across the end to set the start point. There is no need to use the in/out stop.
Step B – first cutting operation
fig 2497 step B left/right stop
fig 2499 position of cutter after first cut
Step C – second cutting operation
Step D – parting off
Doing this using DRO’s
It might appear this could just as well be done using DRO’s instead of stops. There is a video on Youtube doing this. See. But it is far quicker setting a position using stops than by doing this using DRO’s.