George Thomas' excellent "Workshop Techniques" is not really a text on
workshop techniques, more a description of the building of a UPT (Universal
Pillar Tool), and VDH (Versatile Dividing Head). Many techniques and
tips are for dividing and graduating are covered, although the focus is mainly on these two items.
Looking at the UPT, I realised how numbers are stamped into the outside
of dials and decided that a UPT would be a sensible item to own.
As with some of the other items on these pages, I decided to order a kit
from Hemingway to save
the trouble of making castings.
||30-Nov-2004: I decided to machine the table casting first, as it did
not seem to matter too much which order the parts were made in. It's a
bit of a chore machining the slots...
||This is the finished table casting, it doesn't look too bad. It still
has to be graduated and numbered on the outside rim, although I will leave
that for now while deciding the best way to go about it.
||The base was machined next, note the brass pad used to clamp the pillar
to the base - this still needs a ball handle which will have to wait until
the spherical turning tool is complete.
||The arms are next, although a slight problem has appeared. The original
instructions in Thomas' book clamp the arms to the backplate on a jig to get
the correct alignment. It doesn't look like I have enough room here, and
in any case my backplate is not large enough.
||No problem, I can perform the machining operations on the mini-mill although a jig
is required to line things up. It's a steel plate with a pair of reamed
3/8" holes set 3.500" apart.
||11-Dec-2004: These are the parts that have been made so far. The
top arm has been reamed to size and is complete with the brass pads and bolts
||Assembled for another picture, the kit is starting to take shape. The
unattached arm was bored oversize by mistake, and a failed attempt
to sleeve it cracked the casting shortly after this picture was taken. I
need to buy a replacement casting and take a little more care next time...
||27-Feb-2005: The replacement arm is now complete, so it's all going
to get painted up. First job is to take the pimples off with a file.
The lower arm will have the cast in ends left on - they may be useful later,
the top arm will have them taken off.
||The top arm has been frightened with the file, and sprayed a couple of times
with high build primer. 80 grit silicon carbide paper is used wet to level the
surface between costs, and a smooth finish can be quickly built up. A
rotary tool with a carbide burr is removing some high spots that were missed
first time round.
||10-Mar-2005: The finished article, after three coats of metallic
paint and a couple of coats of clear lacquer. The top arm is shown with
a punch holder and there are plenty of materials left in the kit to make the
tapping attachment and a few other bits and pieces. The base will also be graduated when I finish the
Versatile Dividing Head. When casting
season comes round again, I'll make a base casting to clamp the UPT to
the lathe bed.