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#1 DaleWoodrow

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Posted 15 January 2004 - 08:24 PM

Hi Everyone,

What a great Forum, glad to see so many Ops from all locations offering advice and seeking helpfull pointers.

I'm in the process of building a new rig, and are looking possibly at the MK-V XO modular arm as one of my choices. Are there any operators who own one of these or have used one on a long day shoot with heavy and light loads?

If you have, please provide your thoughts and opinions..

Ideally I like the Pro arm but my money tree hasn't bloomed enough..

Cheers.... :D

Dale

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#2 RobVanGelder

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Posted 09 February 2004 - 09:50 PM

I am just wondering about this design. I have seen it once on the IBC, and it worked as you can expect from this design.
However, I have my doubts about the rigidity of the construction. As we all know, there are problems with some arms regarding hair fractures/cracks and when I look at these segments I see that all the stress is going through some Allen bolts, that hold the parts together. Sure it will work at first, but also after a long and stressfull period (heavy load)? Bolts work themself loose, specially in torqued conditions. Threads can rip apart and it just doesn´t look strong enough to me.
The same elements used in the rig is good, but that is a static setup, with no internal forces. But used in an arm....... I don´t know. :huh: <_<


Rob van Gelder, Bangkok, Thailand
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#3 RobVanGelder

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Posted 09 February 2004 - 09:54 PM

Oh, what happened to the double elbow that I was shown on the same show?
It´s not on this picture anymore. The concept has been abandoned?

Rob van Gelder, Bangkok, Thailand
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#4 Erwin Landau

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Posted 10 February 2004 - 01:46 AM

Hi Rob,

I was in the assumption that the XO arm was designed and build for lighter cameras only. Am I wrong or are there two different Arms in development or construction...

I tried the arm on a couple of occcasions but always with a 2C or there famous weight cage/camera and the LCD Monitor...

Double Elbow...??? Are you refering to the Baer-Bel Arm, that one has the double hinge system (An original CP design that never got to production...)
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#5 RobVanGelder

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Posted 11 February 2004 - 04:38 AM

Hi Erwin,

I recall an IBC (3 years ago?) where Howard showed me a double hinged elbow.
It was a prototype then.
I never saw an MK-V XO-arm again.

Rob van Gelder, Bangkok, Thailand
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#6 RobVanGelder

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Posted 11 February 2004 - 04:46 AM

I was in the assumption that the XO arm was designed and build for lighter cameras only. Am I wrong or are there two different Arms in development or construction...

You could be right, but then again, why do you want to buy 2 arms? Perhaps for that running rig, but it would be a hefty price to pay for a limited use.
(And do we really want to run?)

And we all know what happens if you give us an arm that is in principle capable of carrying heavy cameras but lacks the spring-power: we beef-up the arm with extra heavy springs, elastic bands etc.
The structure might not like that at all.

My belief is dat the basic structure must be capable of lifting the maximum load, without damage. Add springs when needed.

Rob van Gelder, Bangkok, Thailand
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#7 DaleWoodrow

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Posted 11 February 2004 - 06:49 AM

Thanks Rob and Irwin for your input.

After researching into structural tolerances and forces applied to steadicam arms with a mechanical engineer he agreed that the likelyhood of hair line fractures in the arm bones and more so around the allen bolts of the XO Arm would be more evident in this design than compared to others such as Pro and CP 3a etc, mainly because the bones and pivoting sections on any arm must be able to withstand inner torque and torsion from the springs under load held in a static postion, which most arms on the market can provide, until the load and boom range increases the forces on all components, especially the bones and connecting bolts which receive an array of twisting and tensile stresses that ultimately stress the structure as a whole.

So to put it simply, arm bones and pivoting joints, including bolts and rods, should be of a design that can handle more than the maximum tolerances that will be subjected to the arm. Although it is difficult to know exactly the many variances of tolerances in all axis including torsion stresses that any arm will be subjected to in a year of flying various rigs inunder wet and dry conditions, it is safe to say that 3a's and the like have had for many many years great reliability with minimal service and repairs from normal use, not accidental damage.

So in choosing another arm, whether it be for standard flying and the occasional flat out running, a Pro or refurbished 3a would be a good choice, that is of course not to imply that any other arm including the XO arm is not lower in quality or poor in design, but we all choose our equipment with the advice, recommendation from our peers and also purchasing what is appropriate for our needs. So thanks guys for your thoughts and comments.

Dale Woodrow
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#8 thomas-english

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Posted 11 February 2004 - 10:56 AM

i used howards new prototype arm on a load of jobs because i was short. it had 2 lots of springs that were easily interchangeable, so i was able to put any camera weight i wanted on there, i think he may have said up to an imax. i liked it, it performed well when running really hard... but it was still a prototype and i know he s improved it lots.
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#9 TJ Williams

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Posted 16 March 2004 - 11:21 PM

Two arm to consider in the lower price range might be the arm Derrick Whitehouse is selling the the zippy new arm from Rig. I'm using whitehouses arm and it's the best of three Cp classic arms i've owned. Lots of good comment about the rig engineering arm also.
TJ
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#10 JamieSilverstein

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Posted 22 March 2004 - 05:11 AM

I have been using my Masters arm (the only thing Masters left of my rig) for the past 7 Years, so I can't really comment on non iso elastic arms. I have however used the Baer Bel arm and I was very impressed! For the cost it was very responsive, smooth, and had a tremendous boom range. This feature I found very appealing. I never put the arm at the bottom or top of its range and never had to feather the clunk that comes with bottoming or topping out if not careful.
When last looked, they went for about $14000.00. Additionally, a used Masters arm might come for even less than that.
Just a thought about alternatives.
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#11 Howard J Smith

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Posted 13 June 2004 - 10:55 PM

Hi Dale

Sorry I did not see this post before.

The XO arm is a work in progress - I have put this on hold while I was finshing off other big systems....!

The arm is very strong and all the points by Rob (how are you by the way?) I take on board but are un founded (as there is still a hell of lot more metal in there than a normal arm - on these points) and he was refering the the barbell arm as well.(which Marcus (Hi) had left on my stand at IBC)

The stucture of the XO is very strong as it is pulling it self togther and the first prototypes outing was to cover the mounting bike race for the Commemwealth games in manchester 2002 on the back of an custom 6 wheel ATV (that I had also designed) on the worst bumpy road you would ever want to be on a 45 Mph - this was live to the world and only one camera coverage - it performed beautifully so much so the director told us we were on the wrong road!

I will carry on with the devolpment of the XO now the other systems are up and running! When I am happy with it and it is up to the same standard as the rest of the system, I will release it - but not until.
I will keep you all posted on how it is going.

In Answer to Erwins question (good to see you again) the one you tried (silver prototype 2) was with the lighter springs - the aim is to have extra springs for heavier loads.

Thomas used the first proto arm for around 4 months and did not want to give it me back.

Thank you all for your input and interest - I welcome and ideas or suggestions.
I look forward to hearing from you

All the best
Howard J Smith MK-V
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