I've had three of these mounts and none of them have ever worked right. I've used the method mentioned above and it held for at least one night. As I recall, there was an issue with temperature making my adjustments done in the daytime moot. I've also tried brass compression washers between the acorn nut and jam nut. I tried doubling up the jam nut. I tried replacing the acorn nut with a nylock nut. I tried everything, but with any sort of normal use, the jam nut always worked it's way loose when adjusting the altitude.
It's beyond frustrating and not worth the headache. It's a fundamentally flawed design. I applaud those who have made this mount work for them. I'm not convinced their success is repeatable.
I am one of those people who absolutely love their Vixen Custom mounts. I have two Customs (although I only use one of them - the other is a spare I keep as a backup) and a Custom D (pretty much exactly the same as the Custom but with a counterweight).
My first of the Custom mounts I have had since it came to me new back in the late 1980s underneath my Vixen 90M refractor. That was my only scope for decades - it still rides on the Custom mount, and although I have many other scopes and mounts now this combo will be with me 'til the end.
The tension on my original mount has never needed adjusting - it just keeps performing fine year after year. The Custom D, which I just got second-hand a few years ago, was a little trickier. It took a bit of trial and error, as well as a lot of coaching from the great minds on this forum, but I eventually got the tension right and the nut locked adequately so that it, too, resists loosening no matter how many times I move it.
Is the mount perfect? No, I would definitely prefer if it didn't have to be reset every 30° or so. And I understand the frustration involved in getting the tension right. But once you do, it can be a joy to use!
Edited by marcyc, 24 October 2024 - 11:20 PM.