J
johnpipe108
Guest
There is a simple technique for turning very small pieces safely on a lathe, by mounting between 60 degree centers, dead center in the lathe head, live (ball-bearing) in the tailstock. The small parts can be hollow, as in the 1:24-scale periscope shear example following, or simply have a small hole drilled in the center of each end; the smallest piece I have turned this way was a bead-end for a Uilleann bagpipe tuning-pin, about 1/4in diameter and about 1/2in long, with a 3/32in through hole for the pin.
A tubular structure starts by end-boring through the piece, after having marked the centers on both ends; the piece will be held by hand and advanced with the tail-stock hand-wheel:
The tools must be sharp, and speeds should be from medium to high as inertia of the spinning piece is important to the technique. Here is the previously bored blank mounted up between the centers:
Here is the same roughed down, with a finished shear for comparison:
All sorts of small work can be done this way, including various hollow shapes so long as one has a pair of centers to fit. Using 60-degree centers means there are no spurs to catch tools or your fingers, so one can cut in quite close, right up against the spinning center in fact. Also, if the tool digs in and catches on the work, instead of the piece flying off into space it simply stops spinning while the still moving center makes a shrieking noise from the friction!
HTH,
Regards, Johnpipe
A tubular structure starts by end-boring through the piece, after having marked the centers on both ends; the piece will be held by hand and advanced with the tail-stock hand-wheel:
The tools must be sharp, and speeds should be from medium to high as inertia of the spinning piece is important to the technique. Here is the previously bored blank mounted up between the centers:
Here is the same roughed down, with a finished shear for comparison:
All sorts of small work can be done this way, including various hollow shapes so long as one has a pair of centers to fit. Using 60-degree centers means there are no spurs to catch tools or your fingers, so one can cut in quite close, right up against the spinning center in fact. Also, if the tool digs in and catches on the work, instead of the piece flying off into space it simply stops spinning while the still moving center makes a shrieking noise from the friction!
HTH,
Regards, Johnpipe