ARCA heads with safety lock. Are there any?

mickledore

mickledore

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I have a Manfrotto MHXPRO-BHQ6 tripod head. I like it. It does what I want. Manfrotto have finally woken up to the ARCA revolution.

This locks the plate by means of the usual screw mechanism.It pushes a spring loaded plate into the ARCA plate groove and screws tight. Upon release the spring loaded plate continues to hold the ARCA plate in a loose grip, until a release button is pressed. Belt and braces job, but we all know how easily ARCA plates can slide about. Not every plate/L bracket has security screws inbuilt.
The trouble is the spring loaded mechanism for the release plate gets loaded up with carp and crud. This stops the spring working as it should, so when the retaining screw is tightened the clamp goes under the plate and not into the groove. Then the head has to be dismantled to clean the spring mechanism. Bit of PIA!
Both @Mr Perceptive and I have had that sinking feeling when our dearly loved cameras slide off what we thought was a secure position.
Yes, I know we should double check, then triple check everything, but sometimes we'd rather take a shot than think about taking it!

Does anyone know of decent quality ARCA heads that have some form of idiot proof security feature that will prevent accidental or unintentional release of camera bodies onto a hard floor?
I've trawled 'tinterweb but cant see anything. Even the wonderful Gitzo seem just to rely on their users relying solely on Gitzo plates.
 
My Sirui head has a spring-loaded stud which pops up under the plate to stop it sliding off. The release button seems to be well shielded within the clamp.
 
Thanks. The Manfrotto has one of those too, but it only works when the securing plate is located in the groove, and that's the main problem.
 
Having seen David's camera hit the deck I have taken to just screw the camera to the original threaded plate that came with my head.
Doesn't take much longer than tightening/loosening the Arca clamp, much safer and makes it easier to fold back the legs if you have a traveler type tripod

Did think of a safety cord type arrangement, but it over complicates a simple solution to the problem

So no, I can't think of a head with a safety device that would stop the camera taking a tumble

p.s. hope the knee is healing up well and you will soon be back out in the wild
 
Yes. You went very quiet for a while:eek:
As it's happened to both of us the assumption must be that there is a design/manufacturing flaw. Hence the search for an alternative.

Knee is OK but ligaments at the back are causing problems. They don't want to stretch. Off to a sports physio on Monday.
 
It sounds a bit like Manfrotto might have over-complicated the simple concept of the Arca system, which is just a dovetailed vice and matching plate, and a standard screw-operated clamp without this extra 'safety' feature would actually be less likely to cause problems.
 
Retune said:
It sounds a bit like Manfrotto might have over-complicated the simple concept of the Arca system, which is just a dovetailed vice and matching plate, and a standard screw-operated clamp without this extra 'safety' feature would actually be less likely to cause problems.
Click to expand...
Yes. That does seem to be the problem. They have engineered in a weakness!
 
There are basically two types of Arca-Swiss safety lock, those that prevent the clamp screw from loosening (eg Benro) and the more common ones that stop the plate from sliding out.

I prefer the latter type and the two popular methods are a spring-loaded pin in the clamp that pops up under the plate, and the standard Arca-Swiss method with a stud at either end of the plate. I prefer the latter, which is simple, easy and foolproof. Almost all plates have these studs, but some don't - like my Markins L-bracket. So...

Drill a small hole at the end of the plate and put a little (2mm wide) cable-tie through it, wrapping around the edge that mates with the clamp so it can't slide out. I also use Peak Design's Anchors to serve the same function and this also puts the carrying strap in the ideal position for me :)

Cable ties from any DIY store or https://www.amazon.co.uk/SODIAL-150...qid=1496491337&sr=1-1&keywords=cable+ties+2mm

Peak Design Anchors https://www.peakdesign.com/all/anchors-4-pack
 
Thaks Hoppy. Lots of useful stuff in there as always.

The problem here is not quite the same as the one you are trying to cure. Once the L Bracket is on the head, and the retaining clamp plate is in the groove then everything works just fine and the camera cannot accidentally release. Just as it should be.

What happens with this head is that the sliding plate that screws up into the groove has a spring loaded release built into it. When the control button is turned to release, the camera cannot be removed from the head until a second "security" button is pressed. This is spring loaded and finally releases the clamp.
The problem is that dirt and muck get into the spring mechanism meaning that when not in use it is not fully extended. So when the camera is placed on the top of the head the plate is not located directly in line with the bracket groove. It only needs to be a little bit out of line so that when the clamp is tightened the gripping plate slides under the bracket. The assumption is that you have tightened up the clamp onto the bracket, but in reality the clamp has tightened up onto nothing, and the camera is just sitting there unfixed. Small margins I accept, but big problems if you assume that the camera is safely locked in place.
I was lucky in that my camera only fell a very short distance and I cushioned the fall. My friend^^^now has a cracked focussing screen and other internal damage.

The idea of a security lock is appealing. You can see the red button that is the cause of the problem here...
manfrotto.JPG
The trouble is that dirt has an easy - and potentially expensive - way in.
 
mickledore said:
Thaks Hoppy. Lots of useful stuff in there as always.

The problem here is not quite the same as the one you are trying to cure. Once the L Bracket is on the head, and the retaining clamp plate is in the groove then everything works just fine and the camera cannot accidentally release. Just as it should be.

What happens with this head is that the sliding plate that screws up into the groove has a spring loaded release built into it. When the control button is turned to release, the camera cannot be removed from the head until a second "security" button is pressed. This is spring loaded and finally releases the clamp.
The problem is that dirt and muck get into the spring mechanism meaning that when not in use it is not fully extended. So when the camera is placed on the top of the head the plate is not located directly in line with the bracket groove. It only needs to be a little bit out of line so that when the clamp is tightened the gripping plate slides under the bracket. The assumption is that you have tightened up the clamp onto the bracket, but in reality the clamp has tightened up onto nothing, and the camera is just sitting there unfixed. Small margins I accept, but big problems if you assume that the camera is safely locked in place.
I was lucky in that my camera only fell a very short distance and I cushioned the fall. My friend^^^now has a cracked focussing screen and other internal damage.

The idea of a security lock is appealing. You can see the red button that is the cause of the problem here...
View attachment 103387
The trouble is that dirt has an easy - and potentially expensive - way in.
Click to expand...

One of the best features of the basic Arca-Swiss system is its beautifully functional simplicity. Why other manufacturers persist in meddling with it I really don't know - nobody has managed to improve it IMHO.

In your position, if you can't get along with the Manfrotto, then I would either disable the lock somehow or replace the clamp. That plate could easily be fitted with a lock-stop as I described, though I'd replace it with one of the more usual design that a) has stop-studs built in, and b) doesn't have that over-hanging edge which conceals the dovetail edge so you can't see if it's properly located or not.
 
Yes indeed. Manfrotto do seem to have been a bit tardy getting into the ARCA system, and now they seem to have over engineered things.
I think a replacement top plate is going to have to be seriously looked into.
 
mickledore said:
Yes indeed. Manfrotto do seem to have been a bit tardy getting into the ARCA system, and now they seem to have over engineered things.
I think a replacement top plate is going to have to be seriously looked into.
Click to expand...

:thumbs:

I use the cheapest clamps and plates off Amazon/ebay, all high quality. I must have a couple of dozen plates at least, maybe ten clamps (I sometimes need a quite a few for my work ;)) and while a few of them vary very slightly, they all fit and work interchangeably. The problem is there's no Arca-Swiss published standard, so one company copies another and, I guess, tiny differences creep in that way.
 
being paranoid since i dropped my 300mm f4 and nikon 7100 off my monopod many moons ago and damaged both lens and camera, how it come undone god knows
i modified my head and also tether the camera and lens with some 8mm bungy cord, you can buy this on fleebay quite cheap, since i have used this it has never worried me
being a bungy cord it will fit all lenses, and i also use this on my 500mm f4 without any worry, i used zip ties for securing the cord loops,I fit lens to monopod first then put loop
on lens then camera on.
.DSC_5208_2664.JPG
DSC_5210_2666.JPG
 
Retune said:
I've never tried this, but various companies sell adapters or kits including both an Arca-type clamp and an adapter that are designed to lock on to the stem fitting of a Manfrotto head (once you've removed the original clamp) - e.g.: https://www.amazon.co.uk/Adapter-CP-58-Arca-Swiss-Compatible-Manfrotto-Replacement/dp/B01CAO7PR4
Click to expand...
Thank you. That looks interesting. I can't see how to disable the spring loaded safety feature on mine and still be able to use the clamp.
Only drawback is that my L Bracket doesn't have the little retaining bolts in the right place, but another member on here has engineering kit and has offered to drill and tap for me.
Same solution, different methods.
Thank you.
 
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