Spotting scope mounting plate

[Crunchy]

Ok what am I doing wrong?  This has been driving me nuts for years.  Swarovski STM spotter.  Gitzo fluid head and mounting plate.  The brass stud is too small and for the hole on the bottom of the spotter so eventually the screw will loosen.   Do I need a different plate?  I would assume the holes are all the same size. 

[Stein]

One thing I found out is that although they are sold as interchangeable and all the same size from brand to brand and model to model, the dimensions on plates are all slightly different.  I've never had a brass button not fit, but certainly the dimensions of Arca plates vary.

Are you sure the brass button is too big and not just slightly off center? 

I gave up on cheap arca gear and went with one brand so they are all pretty similar from glass to glass.

[Crunchy]

The brass button is too small in diameter.  if it were bigger the scope would not be able to wiggle side to side and work the mounting screw out.  That button should lock or prevent side to side motion

[elkaholic123]

The brass button is too small in diameter.  if it were bigger the scope would not be able to wiggle side to side and work the mounting screw out.  That button should lock or prevent side to side motion

How far is pin sticking out? Might need to have it poke out further!

[kentrek]

Not a popular opinion but ditch that plate, get a bi directional arca plate from RRS, no rubber just metal on metal and then use the 3/8s stud and then drill and tap your own 1/4-20 and then on top of that use a bit of loctite blackmax 380 between the two surfaces but not in the threads