# Arca style clamps



## ForumMuppet (Sep 3, 2013)

I've seen the 1" Kirk clamp method recommended several times on these forums and always have the question come into my mind of, do you guys worry about the thumb knob of the clamp coming loose and your gear go crashing to the ground? All of the arca clamps I have are the RRS lever models, which seem pretty solid to me. No experience with the knob model ones to know how snug they are and if there is any slippage. Or am I just being too paranoid?

How about a arca style plate on the top of a monopod? Right now I use the 1/4"-20 screw on the monopod to attach the lens plate. Would it be safe to get a RRS lever clamp and attach that instead? How about when walking with the tripod/lens over your shoulder from one location to another? Is there any worry of the lens coming out of the clamp and tumbling to the ground?


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## wle (Sep 6, 2013)

I have the RRS lever clamp on my tripod and the Kirk 1" clamp on my Joby strap. Believe both are in appropriate location. Not worried about lever being snagged and opened on tripod but I am on strap. I may tend to over tighten the knob on the Kirk. 

I'm more concerned about camera being jerked off my shoulder by the neck strap hooking on something as I carry tripod over my shoulder. Now with Kirk on carry strap I can't put camera on tripod without first removing the strap. All is good now.


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## neuroanatomist (Sep 6, 2013)

I have four RRS lever clamps on tripods and heads. 

I use Kirk 1" clamps (knob style) on both of my Blackrapid straps, I've never had one loosen up unintentionally. 

I have the RRS knob clamp on my monopod head, because the way I carry that rig over my shoulder risks catching the lever on a backpack strap. Never had that knob loosen, either.


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## ForumMuppet (Sep 6, 2013)

I posted this question to the RRS website via email and this is the reply I got from Erik at RRS:

"I can understand your hesitation given the size of the mini-clamp, but I can assure you the mechanics are the exact same, and the load rating is also the exact same as all of our screw-knob style clamps that we have used over the last 20+ years for setups including 800mm/f5.6 prime lenses, or $150,000 cinema camera setups. Because it is based on a screw-knob design, the load rating is technically infinite, by simply tightening down the knob. However having said that, as with any system that is supporting your equipment, you should always be mindful of your equipment and never fully rely on a single point system without double checking each and every point of the system beforehand."


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## eli452 (Sep 6, 2013)

I use RRS (B2-FAB-F 38mm clamp for Blackrapid, B2-mAS on BH-25 ), Markins (QR-60 60mm on Q10 ball head and RRS Multi-purpose rail & QR-48 48mm on Q3 ball head on monopod) and Wimberley (M-8 Perpendicular Plate) all Knob Release. Never had a problem with any of them. My refrainment from lever release is in some part fear of accidental release if caught in a strap and part sheer paranoia.


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## Jim O (Sep 7, 2013)

I only use the knob style. Call me old fashioned, but I am leery that a lever will unintentionally pop loose.

I have an old Arca-Swiss B1 that I recently retrofitted with a Wimberley knob style clamp. The Wimberley's are really nice folks and very helpful.

I use a RRS monopod head with the knob style clamp.

I also have smaller, though quite strong, Linhoff head that I've modified with an *old* RRS knob style clamp. I must have bought the plate 15 years ago when the Bryan Geyer owned RRS, and unfortunately it does not have a captive screw. I used some kind of plumbers glue to seat it in there and I doubt it's _ever_ coming out. Actually the instructions were given to me by Bryan Geyer himself.


Anyway, *none* of them have ever come loose.


BTW, if you're paranoid about using the 1" clamps, you can use a setup like this as a safety:


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## Jim Saunders (Sep 7, 2013)

Jim O said:


> BTW, if you're paranoid about using the 1" clamps, you can use a setup like this as a safety:



Maybe we should write that one down  (Which works better if you saw that particular Far Side cartoon)

Jim


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