Second, re brittle epoxy: Golf club glue. There is an epoxy specially formulated for high impact strength. It retains a bit of elasticity rather than becoming brittle. It is designed to glue golf club heads to shaft, etc. I ordered some. Brampton and GolfWorks seem to be the two main brands of it. Impact of a golf club face on a ball should be somewhat similar to recoil.
I'm not sure that I follow that logic, using a flexible epoxy, unless you simply want to seal out moisture.
That product is used in a different application. Since there is no fastener holding the golf club head to the shaft, flexible epoxy must fix the golf head to the club by adhesion. Impact and peeling resistance are very desirable. But our scope bases are held in place with fasteners, which provide a clamp load. I don't want a flexible spacer, between the base and receiver. Just like I don't want a flexible washer in a bolted joint, unless it is required for vibration isolation or some other special application.
