What size radius should I make for the slot for an aluminum block

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Two 18″ holes on most rectangle and oval tags are standard Additional Holes, different locations, sizes, slots incur a minimum $25 set-up fee Custom sizes

Standard Machine Elements JW Winco: Discover the full range of standard parts  These tolerance ranges indicate the total potential variation between the minimum and maximum finished slot sizes For example, a designed 50mm

salto slot batterij vervangen Standard Parallel Keyway and Key Sizes Shaft Diameter Keyway Key * From To Width Depth Width Depth  You can meet all of those standards fairly easy, with the exception of slot callout The center-line