Model Engineers’ Workshop – August 2019

26 http://www.model-engineer.co.uk Model Engineers’ Workshop

This month Jason Ballamy discusses diff erent options for indexing and dividing

Milling for

Beginners

Part 12 - INDEXING AND

DIVIDING

Basic Indexing
Indexing is the process of rotating the work
against a fi xed reference point or surface
to give the required number of faces or
points. In its simplest form the fi xed jaw of
the milling vice can be used to form square
items by placing the previously machined
horizontal surface against the vertical jaw,
photo 146.
This really only works if it is practical
to get the machined face in contact with

the jaw which is not always possible for

example when creating a square on the

end of a long piece of stock in which case

other means of indexing need to be used.

If the work is suffi ciently long enough to

protrude out of the opposite end of the vice

to where you are cutting it then a vee block

can be clamped onto the end and a try-

square used to set the vee block as it and

the work are reset at 90degree intervals. If

you don’t have a vee block, then a piece of

square stock could be drilled through to suit

the rod and temporarily bonded on photos

147 & 148.

Indexing with Collet Blocks

A step up from these basic methods if

you already have a set of collets is to use

a collet block, these come in both square

and hexagonal giving the option for hex

head screws and bolts. ER Collet blocks are

probably the most common ones in use by

146 147

148 149

Using vice jaw to index 90degrees Vee block used to index 4 positions

Close-up of square used to index the vee block ER Block showing back of nut against vice jaws