David Billington wrote:
I have been asked if I can make some items that use a steel rod tapering
from 1/4" down to 3/32" over about 7". All I can think of at the moment
is to try and turn it but using a special tailstock centre to allow it
to be placed in tension and offset the tailstock to set the taper as
normal. The taper doesn't have to be accurate, it could be slightly
barreled, but does need to be smooth. Any body have any better ideas.


I had to make a small triblet for the jewellery I make. It consists of a
silver-steel rod that tapers from 9mm to 1.8mm over a distance of about
150mm. I turned it on my lathe using nothing but the standard equipment
- I don't have a taper attachment and the top slide travel is only 70mm.

I machined the taper in stages, so the the cutting tool was never more
than 30mm from the chuck.
I centre drilled the end, set the topslide over to the the required
angle, chucked the rod so that only 30mm protruded supported it with a
live centre in the tailstock, then started to cut the taper until it got
too close to the live centre. At this point I continued the cut by
leaving a knob on the end where the centre supported the rod. It got
tricky at this point 'cos I wanted to get the end of the taper as small
as 1.8mm, but, by using a sharp tool that could cut in both directions,
this was finally done. The rod was then extended a further 30mm and,
with suitable light cuts, the taper cutting was continued until it met
the previous one. The process was repeated until there was no more to
cut, then the knob was removed and the surface improved with emery cloth.

It made a very nice triblet that gets a lot of use - in fact I made two,
one for a friend.


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Regards, Gary Wooding
(To reply by email, change feet to foot in my address)