Jump to content



Photo

Socket Block issues...


  • Please log in to reply
51 replies to this topic

#1 Erwin Landau

Erwin Landau

    Advanced Member

  • Moderators
  • PipPipPip
  • 1699 posts
  • TBD

Posted 23 April 2004 - 01:25 AM

Tough call... Arm or Vest Topic... Let's go with Vest....


Socket Block issues...

The Back mounted Harness and the Steadicam Arm.

I'm using the DSD Harness in conjunction with the PRO Arm.

I lately developed extreme deformations on my Male Socket Block (Arm Socket Block). In the 2 grooves where you tighten the Arm down, they are about to break off... and parts did... They started to appear during 2 excessive days off of a hard mount shooting from a Motorcycle a couple of weeks ago (GPI repIaced mine...) Using the Klassen build Hardmount, same design as the Backmounted Harness. I was told that that had to do with the fact that a DSD Vest/Hardmount where used and that the Socket Block Assembly was not designed for the DSD style connection...

Front Mounted Vests are utilizing the Thumb screws only for safety and to adjust jaw of the rig assembly as weight of the Rig basically pulls the pin of the Male socket block further into the Female counter part (The proof of that was at the PRO workshop, when a 3A arm permanently wedged it self into a PRO Vest, and I mean for good... no hammer was to small and I think the bandsaw took care of that), versus with the DSD, where the thumb screws actually are holding the whole rig assembly (Arm, Rig, Camera, etc.) in place, besides providing a side to side adjustment.

We had some extensive discussions on the last PRO workshop (last week).... Starting with the DSD/Klassen Socket Block having to be made out of steel or Titanium versus the still used Aluminium... up to having to redesign the whole Arm to Vest connection... etc...

Just another fun day in Steadicam Land...


Erwin "Titanium makes a very unique sound when it brakes" Landau, SOC
www.landaucamera.com
  • 0

#2 JakePollock

JakePollock

    Advanced Member

  • Members
  • PipPipPip
  • 55 posts

Posted 23 April 2004 - 07:33 AM

I'd guess you made a pretty interesting sound yourself when that titanium snapped!

Jake Pollock
Taipei, Taiwan
  • 0

#3 Brad Hruboska

Brad Hruboska

    Advanced Member

  • Sustaining Members
  • 157 posts
  • Toronto

Posted 23 April 2004 - 09:01 AM

I would be very interested to hear what Walter has to say on this topic, As I own both a vest and Hardmount of the same configuration and a Pro Arm... Visions of cameras hitting the pavement at high speeds have that career ending twang that would make me leave the junk on the truck and drive directly to the nearest bar and start work on my food services resume...... :o
  • 0

#4 Rich Cottrell

Rich Cottrell

    Advanced Member

  • Sustaining Members
  • 178 posts
  • Erdenheim, PA

Posted 23 April 2004 - 09:44 AM

I too have been thinking about this...
I have a Pro arm on my DSD vest. The top screw is always working its way out. There have been many times when i go to dock the sled, and when i go to take the arm off i realize that the top screw has worked itself out 1/2 way!

I have been cranking down on the little fellas and praying i never loose my arm and rig. Now you got me worried about breaking the arms scoker block.

Erin, Did Pro replace the socket block as part of the lifetime warranty?
thanks,
rich
  • 0

#5 RobVanGelder

RobVanGelder

    Advanced Member

  • Sustaining Members
  • 919 posts
  • Bangkok, Thailand

Posted 23 April 2004 - 10:33 AM

Erwin, I had a similar situation with my Pro-gear arm (don´t frown now,it actually performs very nice!).

During my last workshop, we used it also hard mounted on a dolly, and after a while the instructor showed me the deformation, but mostly in the adjustible bolts.
They turned out to be from the wrong kind of alloy, so we replaced them with much stronger bolts, no problem now.

The main thing, with hard mount, is that you as an operator will not feel the limit of the arm when you hit it. Normally, when you are near the limit, you will feel that in your body and adjust to it, this is you bent your knees more to get lower.

But with a hard mount, you can reach the same mechanical limit from the arm without you noticing it and at that moment the weakest link will break.
In my case the bolds, but since they have been replaced for a stronger kind, very likely something else will go next.

So with any hard mount it is very important not to reach the mechanical limit of the arm, specially fully down. Going over a speedbump on high speed can really tear the whole thing apart if you don´t adjust it carefully.

Rob van Gelder, Bangkok, Thailand
  • 0

#6 Alec Jarnagin SOC

Alec Jarnagin SOC

    Advanced Member

  • Moderators
  • PipPipPip
  • 1800 posts
  • New York City, USA

Posted 23 April 2004 - 10:46 AM

Erwin,

I suspect the easiest solution for the time being is to use the more traditional style garfield mounts (Jerry Hill, CP, etc) for vehicle mount situations. This just means that if you use a DSD/Klassen vest, that you have to swap your male (arm) socket block around between soft mounts and hard mounts. I can't imagine that there is enough pressure on the arm to deform it while wearing it on your body (these vests have been in the field for a number of years now). Very interesting find though - thank you for sharing.
  • 0

#7 RobVanGelder

RobVanGelder

    Advanced Member

  • Sustaining Members
  • 919 posts
  • Bangkok, Thailand

Posted 23 April 2004 - 10:47 AM

One other question, in your setup on the motorcycle, how was the socket block oriented when looking at the direction of the movement?

It sounds to me, since you have cracks in the two hollow grooves where the adjustment screws fit, that it was at a 90 degrees angle to the direction of the movement, thus having the greatest force on those 2 screws and their point of impact.
Is this right?

Personally I am not convinced that the original design was not made to be used in a DSD config. I doubt that, when they designed the block, at that early stage there was even an idea about this kind of mounting.

My guess is that with the heavier camera´s/payload nowadays, the original design might show it´s weaknesses, regardless of the way of attachtment.

I say this because I had a one occasion where the screws from my original 3a socket were really biting viciously in the IIIa arm-block I had then, also after a heavy hard mounted shoot on a quad.
And here the position of the socket and block was similar as it would have been on a front-mounted vest.


Rob van Gelder
  • 0

#8 Anthony Hardwick

Anthony Hardwick

    Advanced Member

  • Members
  • PipPipPip
  • 145 posts
  • Pasadena, CA

Posted 23 April 2004 - 10:59 AM

Erwin,

I suspect the easiest solution for the time being is to use the more traditional style garfield mounts (Jerry Hill, CP, etc) for vehicle mount situations.  This just means that if you use a DSD/Klassen vest, that you have to swap your male (arm) socket block around between soft mounts and hard mounts.  I can't imagine that there is enough pressure on the arm to deform it while wearing it on your body (these vests have been in the field for a number of years now).  Very interesting find though - thank you for sharing.

Alec,

I actually had a problem with the first Garfield mount I bought that was of the more traditional variety you mention. On the very first use, it damaged the titanium socket block of my arm. It turns out that the machining of the Garfield mount in question was not quite up to the specs for the socket block, and thus prevented perfect mating. As a result the screws bit down on the edge of my arm's male socket block. I knew this was occuring at the time, but I was on a job, and I had no other alternative to get the shot, and believe me, I was sweating the security of the connection.

The shot went off fine, but my arm's socket block needed to be remachined after that. I wasn't very happy about that, and I immediately returned the Garfield mount to the manufacturer for a full refund. I then bought a Klassen Hard mount, which has less flex, is built and designed better, and costs less than that first one. It's also machined to the right specs for the mating of the male and female parts of the socket block.

Also, with a Tiffen style arm (with aircraft pin) it's no big deal to turn the arm's socket block around, but on a Pro arm (and others?) it's a bigger pain in the ass in the field.

Anthony
  • 0

#9 Benjamin Treplin

Benjamin Treplin

    Advanced Member

  • Sustaining Members
  • 298 posts
  • Berlin - Germany

Posted 23 April 2004 - 04:05 PM

Hi all,
I?d like throw in my two cents.
Rob, if you reach the mechanical limits of your arm while hard mounted, because of ruff terrain, any arm is likely to fall apart, not only the socket block. Steadicam arms are not designed to withstand such kind of forces. Garrett addressed this issue on the first workshop I participated.
You need to build a frame around the hard mount that is big enough to handle the maximum or your desired arm range. On each corner you connect strong rubber bands and connect them to end of the arm. The config has to be adjusted so the arm can?t reach the limit in any direction. Make sure your arm, arm post and gimbal are secured to each other.
This way you are able to handle terrain that would normally exceed your arm range. Works like a charm.
By the way, the original steadicam aircraft pin fits perfectly into the PRO arm.

Benjamin
  • 0

#10 Erwin Landau

Erwin Landau

    Advanced Member

  • Moderators
  • PipPipPip
  • 1699 posts
  • TBD

Posted 23 April 2004 - 04:17 PM

I'd guess you made a pretty interesting sound yourself when that titanium snapped!

Jake Pollock


Jake,

It sounded as if a gun went off. Then after the piece broke off, the Arm pulled out and the whole rig swung towards me, stopped by the Vest Socket that instantly took a big hit and bend as well... a couple of people hit the deck... It would have been funny if I hadn't wet my pants...

I just made it to my Stand before anything bigger happend...

  I would be very interested to hear what Walter has to say on this topic


Brad,

Unfortunately I was not able to get in contact with Walter at that point as he was at NAB, also I was working... as soon as I get him on the phone I'll let you know...


Erwin, Did Pro replace the socket block as part of the lifetime warranty?
thanks,
rich


That is interesting...
I never had the screw back out, but then again my lower screw is frozen shut and the top is always all the way in and locked...

I was told by GPI that the Male Socket Block is not a part of the PRO Arm Chassis and is not covered by the life time warranty...
It got finally replaced because of other findings, the part that I accidently received was an old prototype and was never supposed to leave the factory. Mix up...

But I can understand that they do not warranty that part for more then 1 year. It's a high stress part that has proven to fail in the past.
I know of a couple of operators that had the male Socket fail completely, Stephen Campanelli comes to mind that had his fail about 2 weeks ago...

Also the Female Socket Block has failed with catastrophic consequenses... Craig Fikse's Socket on his Hardmount (Steel if I remember right) broke in 2 after a couple of takes... DeRose style Hardmount with regular Female Socket Block...

Charles Papert's Arm got pulled out of the Socket while hardmounted taking a quick corner... One XL down for good and $8'000.- damage to the rig, the result....


Any one has a good Idea how and with what to replace the out dated Socket Block assembly...

There should be a better way... Ideas?

BTW: I'm sure one of the reasons that that never happend would be the fact that we don't want to buy new parts and especially when we upgrade to a new piece of equipment like an Arm or a Vest... right?????


Erwin "Forcing the Evolution of Parts" Landau, SOC
www.landaucamera.com
  • 0

#11 guillermo nespolo

guillermo nespolo

    Advanced Member

  • Members
  • PipPipPip
  • 295 posts

Posted 23 April 2004 - 04:31 PM

if i here in argetina force that way to a upgrade of my equipment i better star thinking of a upgrade of country cause i will never touch a film camera again :D :D :D :D


ps erwin i want that arri 3 low mode ;) ;) ;)
  • 0

#12 Benjamin Treplin

Benjamin Treplin

    Advanced Member

  • Sustaining Members
  • 298 posts
  • Berlin - Germany

Posted 23 April 2004 - 04:32 PM

Erwin,
how about the joint where the aircraft pin is placed.
It is possible to design a complete new connection between mitchell / euro mount and attach the arm with the aircraft pin to it.

Benjamin
  • 0

#13 Anthony Hardwick

Anthony Hardwick

    Advanced Member

  • Members
  • PipPipPip
  • 145 posts
  • Pasadena, CA

Posted 23 April 2004 - 04:33 PM

Okay Erwin, now we're taking this thread more into Arm territory... Maybe there should be a category called "Homeless" for homeless threads?

By the way, the original steadicam aircraft pin fits perfectly into the PRO arm.

Benjamin


Is this at the expense of adding flex to the joint though? I think it must. From my observations, the Pro arm has less flex at that joint (socket block to arm) than a Master Series Iso-Elastic with an aircraft Pin. I have never tried or seen an aircraft pin fitted to a Pro arm, so I really have no idea if this would introduce more flex. Something tells me it would. If it doesn't, then it seems that this would be a great way to go for the convenience of being able to change the orientation quickly. There have been more than a couple of times that I've needed to do just that with my Master Series arm, and it has been a relief to have the A/C pin.
  • 0

#14 Benjamin Treplin

Benjamin Treplin

    Advanced Member

  • Sustaining Members
  • 298 posts
  • Berlin - Germany

Posted 23 April 2004 - 04:48 PM

Anthony,
the original PRO bolt has the same diameter as the aircraft pin. You?re not adding an extra connection, you use the one already existing. I didn?t experience any additional flexing in the arm. Give it a try, it is only about 140 USD from Tiffen.

Benjamin
  • 0

#15 Benjamin Treplin

Benjamin Treplin

    Advanced Member

  • Sustaining Members
  • 298 posts
  • Berlin - Germany

Posted 23 April 2004 - 04:56 PM

here is the picture
  • 0




PLC - Bartech

GPI Pro Systems

Teradek

Betz Tools for Stabilizers

Omnishot Systems

BOXX

PLC Electronics Solutions

Wireless Video Systems

Engineered Cinema Solutions

IDX

SkyDreams

Boland Communications

Varizoom Follow Focus

Paralinx LLC

Ritter Battery

rebotnix Technologies

Media Blackout - Custom Cables and AKS