The DOT fasteners are marked on the inside of the socket where the red arrow points.
These are the setting tools I use and the posts roll over perfectly every time.
I use the cap anvil on top of a mini steel anvil and make sure the post height matches the material thickness.
I started with Tandy snaps and experienced the same problem you're having, they're garbage too!
You're welcome Bob.
If you lay your straps out and clamp the far end to keep the tension it's quite simple and the results as you can see in the picture are better than you would think.
I've skived a few dog collars and this was the first belt blank but I know now it works well and am happy to share it.
If you don't have a blade jig or stone you can most likely get your blades sharpened at any saw sharpening service.
I have a few different planes and chisels so I bought a jig and the wet stone.
Good control with the plane.
It stops cutting after a few layers then you just lower with a slight turn of the screw, no waves, nice and flat.
For sharp knives you can't beat a good cloth wheel and green compound, it takes seconds to sharpen a blade.
I tried it with super sheen with and without thinning and tried two different cans and the results were the same.
I can't see how a filter makes any difference if the viscosity is right.
Not much help here, I tried those things a few years ago, thinned, not thinned, just couldn't get the thing to work.
Had a spare and tried it and that wouldn't work either.
Now I just use a gravity fed gun.
It works well because the drill bit puts a nice inside tapered end on the post.
Pull the dot snaps come in different post sizes so I like to have a couple to choose from and they roll over real nice with hand punches.