Related Resources: mechanical-tolerances

Measuring and Designing Dovetail Slides

Geometric Tolerances Dimensions

Measuring and Designing Dovetail Slides

Dovetail slides that must be machined accurately to a given width are commonly gaged by using a gage pin of known diameter and measured as indicated by the dimensions x and y.

The gage pin should be small enough so that the point of contact e is somewhat below the corner or edge of the dovetail.

To obtain dimension x for measuring male dovetails, add 1 to the cotangent of one-half the dovetail angle α, multiply by diameter D of the rods used, and add the product to dimension α.

x = D ( 1 + cot 1/2 α ) + a

c = h · cot α

To obtain dimension y for measuring a female dovetail, add 1 to the cotangent of one-half the dovetail angle α, multiply by diameter D of the rod used, and subtract the result from dimension b. Expressing these rules as formulas:

y = b - D ( 1 + cot 1/2 α )

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