The screws on my Low-Angle Adapter are 10-32 UNF; fine thread as opposed to the 10-24 UNC which is coarse thread. That also jives with your photograph.
Number 10 screws are supposed to be 3/16″ nominal, which is 0.1875″ diameter.
Generally, fine threads are used to get more engagement with the material. Coarse threads are used where pull strength is not that important, or where the material is soft. The shallower depth of fine threads would more easily shear and pull out of a soft material. In the case of the Low-Angle Adapter, the strength of the aluminum alloy is high enough that fine threads are the better answer. At least I’m assuming that whoever is doing Wicked Edge’s engineering has come to those conclusions.
My LAA also came with flat-head screws for both upper and lower positions, although there is no countersink at the lower position. A machine set screw would eliminate the head, but you’d need an additional wrench and a very small one at that. The wrench and socket may be too wimpy to produce the required torque. That all would explain why they used a flat-head screw. Same tool, more torque. Better to use the flat-head screw and grind away the unnecessary countersink flange. If the screw still sticks out too far, grind some length off the business end. Buy another 10-32 screw if you need to go back to the longer screw.
If you like, I have some stainless socket-head cap screws in 10-32. Send me a personal mail with your address and I’ll send you a couple.
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