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Milling – alignment – methods – “bent” spigot
Where two spigot are not coaxial but are at an angle to each other then different methods are needed to check that their axes lie in the same plane.
In some cases one of the spigot may well be a workpiece.
In practice there are two key parameters
if their diameters are the same or not
if they are at right angles or something else
Case 1 – same diameter and at right angles
This can easily be checked by using a square
Case 2 – different diameter and at right angles
Devices for doing this are all based on having two v-shaped grooves at right angles.
first – Rawlinson’s device
A similar device is made by Starrett
Case 3 – same diameter at any other angle
This can be aligned using an angle plate. This does assume that the angles of the vertical planes that pass through each of them are parallel.
fig “bent” bushes using an angle plate
Case 4 – different diameter at any other angle
This is the same as case 3. The difference is that there will be a gap between the smaller part and the angle plate. this can be “eliminated” by fiiting two bushes on the narrower part to make it the same effective diameter as the wider part.