I noted a thread from a while ago where someone mentioned having had a small series of custom plates made, but even contacting Really Right Stuff support they have basically no plates for this. They said you could use a 100mm lens plate perhaps. The bottom of the camera is 3" round and it has the female thread and basically nothing but the rim all the way around. See photo below.

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Most options are well below 76mm or 3"... I'm currently using a manfrotto hex plate and older manfrotto head. I'd love to be using my RRS BH-55 head instead.

Any ideas or options?

Things i've already considered / tried...

I've considered buying a piece of home depot 16GA steel and get a bunch of jigsaw blades and just cut a 3" round and drill it in the center and attach it to a small standard arca swiss plate. I thought of using aluminum but figure it wouldn't last unless it was really thick.

I've tried using smaller qr plates and it just wobbles about.

I've considered the 100mm RRS lens plate, it could work but might not be as secure.

Thanks,

Bill