seek information regarding stud sizes of connectors on terminal boards,
and which spade lugs are spec'd to fit each.

by the way, how are spade lugs sized?

Suggest you go to the web sites of the manufacturers of the particular
terminal boards you're interested in and download specifications
(usually pdf documents) that should give you such info; same with the
spade lugs. But generally both would be spec'd for standard screw
sizes: numbers (4, 5, 6, 8, ...) in the US and metric (millimeters)
pretty much everywhere else. Those of us in the US that manufacture
for the international market really are using metric wherever possible,
and some day someone with some real leadership will wake up and get us
really converted over to metric. Sigh. BTW, you can (or at least used
to be able to) get rows of spade lugs on an insulating strip to match
particular barrier terminal blocks, both from the same manufacturer.

wrote:
seek information regarding stud sizes of connectors on terminal boards,
and which spade lugs are spec'd to fit each.

I think you might benefit from looking through the Keystone Electronics
catalog, they have some dimensional drawings.

by the way, how are spade lugs sized?

In the US, #5 or #6 screws are the most common on small barrier
terminal strips. Spade lugs are available in #2, #4, #6, #8, #10, 1/4"
etc. screw sizes.

Tim.