Manfrotto 400 Geared Head Quick Release Plate dimensions

[BVH]

Hello. First post. I have a Manfrotto 400 Geared head coming my way and have been trying to find the diameter of the top of the quick release plates but have found differing numbers. I found 2.95" twice and was hoping someone with a plate could give me its dimensions. I want to mill a conical shaped adapter going from the top of the quick release plate to a 1.5" diameter threaded adapter that screws into the bottom of my 19 lb. searchlight. Any help will be appreciated, especially dimensions taken with a caliper if possible.

[mpirie]

Are you talking about the RC4 adapter plates?

I use several on my cameras, but they are rectangular on 3 sides, and arched on the 4th......a bit like an arched doorway.

What dimensions are you looking for?

Mike

[BVH]

No, not RC4's. These are round and different specs say differing diameters from about 2.75" to 2.95". I think they are unique to this specific Manfrotto 400 head. I'm looking for the largest diameter of the top of the plate, where the 3/8" stud is. I'm being picky in that I would like the measurement in thousandths of an inch only because I have a lathe and will cut my conical adapter to exactly match the plate. Another member gave me a 3" diameter.

https://www.manfrotto.com/be-en/quick-release-plate-high-for-400-geared-head-3263-42mm-400pl-hig/

[mpirie]

Ah, ok, now i see what you're looking for.

I was confused because my 405 and 410 geared heads use RC4 plates.

Sorry, i can't help you with that head.

Mike

[BVH]

Thank you for your efforts to help!