25-04-2019, 03:34 AM
It all seems very simple but aint necessarily so. Many cars are fitted with non standard dia pins. (The original were just under .5 inch to suit standard .5 inch bush bores.) In theory bushes can be .5” before fitting but many are much smaller which complicates reamer alignment but helps if hub slightly bent, as many are.
With the pre Girling hubs the lower bush is blind ended hence the need for a special reamer with blades full dia to the end for the final cut; an irksome Seven complication through the ages.
A reamer with a guide is the ideal, esp if hub slightly bent.
Adjustable reamers useable with Girling have provision for a guide but more difficult to avoid chatter marks than fixed reamer.
The kingpins sometimes distort slightly when the cotter tightened. It is important do not bind in bushes. Not only does it cause wander but the bushes often then turn in hub; another unwanted complication.
The reamer must be turned with a push and pure rotation, side pull causes to cut oversize.
With the pre Girling hubs the lower bush is blind ended hence the need for a special reamer with blades full dia to the end for the final cut; an irksome Seven complication through the ages.
A reamer with a guide is the ideal, esp if hub slightly bent.
Adjustable reamers useable with Girling have provision for a guide but more difficult to avoid chatter marks than fixed reamer.
The kingpins sometimes distort slightly when the cotter tightened. It is important do not bind in bushes. Not only does it cause wander but the bushes often then turn in hub; another unwanted complication.
The reamer must be turned with a push and pure rotation, side pull causes to cut oversize.