From Ron (verified customer) Thanks for your followup message. When digging in my drawer of taps and saw blades I actually found a 12mm 1.75 tap that I’d forgotten I had and hadn’t even opened. So I ran the tap through and as you noted, found it did cut some metal. I have been working on placing-drilling 3 other holes for mounting to my pier. I may end up drilling out the plate hole anyway since it is in the ‘middle’ and the threads make mating to the mount head threaded hole more difficult. I am adapting the plate to mount an Orion HDX110 / EQ8 head on a pipe pier. You might be interested to know that if you added three small threaded holes in the right places the plate with 12mm center hole could be also sold for the HDX110- or Skywatcher EQ8 mount. Orion doesn’t sell anything (other than the tripod model) to mount it on a pier and from what I could find Skywatcher dealers in the US don’t carry adapter plates made in Europe for the Skywatcher version. I tried ordering an EQ-8 adapter plate from Altair Astro in England, but they really screwed up the order or DHL lost it and I never got it, losing much time in the process. They seem really unreliable. Adapting the ADM plate is ‘plan B’ and far less expensive than another US aftermarket maker of mount pier adapters charges. There is an EQ-8/HDX110 base diagram with dimensions PDF drawing on the Orion website I think. Ron
