Thanks to all who replied. After talking with Bruce we went with a combination of a couple of your suggestions. We used thin sheets of cork between the rings and the tube. That alone is holding the tube well. But just to be safe Bruce is going to follow up on Sieg's suggestion. When I made the rings all those years ago I put a single, unthreaded 5mm hole in both of the top rings. So Bruce is going to pass a drill bit down through those holes and drill holes in the tube. He'll then put pins in the holes. The rings, BTW, turned out really nice. While it's only gold plate, there's something about the look of gold... patrick On 14 Mar 2011, at 14:56, ziggy943@xmission.com wrote:
My suggestion is not to use cork. Rather fix the location of the tube. First get some small tube weights so balance can be maintained for different eyepieces. Find the location where balance is achieved. Note the location of the upper ring. Countersink a ΒΌ" screw into the ring, leaving the head to stick into a hole into the tube. Guaranteed not to slip.
Siegfried