As a follow up to this discussion I wanted to look at the final product. I really do not care how nicely the parts nest before riveting but what the final product will look like. Both the Cleveland and Avery dies were what they call spring back dimple dies.
I took two pieces of .025 metal and drilled them all at the same way, they were all dimpled with a C frame.
I used standard Avery dies, Standard Cleveland dies and a standard cleveland die with a Sub Surface die on the lower sheet.
Before riveting the Cleveland dimple with the Subsurface dimple did in fact nest together better then the Avery dies, or the Cleveland dies.
In this picture the left one on your screen is the Cleveland with the Sub Surface die
The centre picture is the standard Cleveland dies
The right one on your screen is the standard Avery dies
There was some warpage during the cutting process but the one on the left did "nest" together better. The hole of the Sub Surface die was visually larger, similar to what was found in my original post on this thread.
Then I riveted the parts using a squeezer and set the heads all the same. The part was cut and the surface buffed.
My apologies for the orientation of the picture
The top picture is the Avery dies.
The middle picture are the Cleveland dies
The bottom picture is the Cleveland die on top and the Cleveland Sub Surface die on the bottom.
Note that all three test pieces are nested firmly together. For overall appearance my preference would be the Avery dimples
I draw your attention to this bottom picture, note the small gap between the top and bottom sheet, next to the rivet. I believe that using the slightly larger Subsurface die on the lower sheet means that there is not enough "material" on the top sheet, with the smaller Cleveland dimple, to fill the hole between the parts and the rivet.
Over the years I have purchased tools from both Cleveland and Avery, they are both excellent suppliers and I have no affiliation with either supplier.
Based on my experiences with the Sub Surface dies I can not recommend their use.

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