With a micrometer measure the outside diameter of the bushing with a 1/4" shank in the bushing. The diameter should be .500 anything under will not be held evenly in the 1/2" router collet. The same is true for the 1/4" I.D. of the bushing (.251) I.D. It can be checked by useing guage pins in .001 increments.
The router collet I.D. should check out at about .501. A collets holding and runout are effected by the fit of the parts used.
The router collet I.D. should check out at about .501. A collets holding and runout are effected by the fit of the parts used.
