[Jacques Reed]

Hi Ian,

Further to previous post:

Just checked my Bible, "Machinery's Handbook" and found American Standard and British Standard dimensions for small solid rivets.

American Standard call them Button Head and my best estimate is they are a 3/8" shank diameter as the shank tolerances are 0.375" to 0.380" Allowing for slight deforming when being driven, that would account for the larger diameter as measured. I can also see a slight taper from under the head to where it was ground off on my sample which indicates a smaller initial diameter.

I measured the diameter of the shop head and at 0.675" I would say it is an American Standard, and not a British Standard rivet. American Standard 3/8” Button Head diameter tolerances 0.646” to 0.684”
Maximum rivet head diameter for a British Standard 3/8" shank Snap Head rivet is 0.656", a fair bit smaller.

I can post all the dimensions on a sketch of the shop head if you would like them.

Cheers,