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Jerry Holway

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Everything posted by Jerry Holway

  1. See the attached file for the pix... here is the text: At the Banning Mills workshop last week (a great time, BTW), we took a good look at several back mount vests from different manufacturers. One common thing in all the back mounted vests: the standard arm to vest connection had the side-to-side adjustment screws on the outside of the armature that wraps from the front to the back. While it is easy to reach the screws in this configuration, they totally reverse the action of the spring in the male socket block. (These are the same screws that control the “fore-aft” adjustment in a traditional front mounted vest.) That spring has been an important part of the arm design since 1976 or so, and its purpose is to pull the arm out of the way as one moves the sled across one’s body. With a back mounted vest, the spring pushes the arm towards the sled – which is not a good thing. A partial solution would be to remove that spring – at least that would keep the arm from being pushed towards the sled. Better would be to have a spare socket block with the spring removed, or better yet get someone to engineer a spring/socket block that would reverse the “normal” direction of the spring just for your back mounted vest. I heard about, but did not see at the workshop nor could not find for sure, that Walter Klassen made a springless block, which would help. BTW, the Tiffen third arm segment has the side-to side adjustment screws on the inside to preserve the proper spring action and keep the arm moving out of the way. In the pix, the 3rd arm segment is set up for regular side operating. It is, of course, reversable for goofy side operating. At the Banning Mills workshop last week.docx
  2. Shameless plug: I make several of these brackets, and also make custom parts as well - go to jerryholway.com to find the most recent part and price list. Most of the brackets mount on rods, but a few mount to a long dovetail... here's one of them that expands for different width rod mounting:
  3. The Ultra one uses the panavision std rods at the time of .620 diameter, but the spacing for the rods is not standard - it was just keeping the sled width as small as possible. I doubt it matches anything Panavision has. 15mm rod clamps will not work on these rods
  4. I've been busy making new things (some not ready for prime time yet) and improving others. Here are the latest. sorry for the screen shot quality....
  5. There are lots of choices other than these two. You should experiment and find the vest that fits you and not because it is anyone else's choice. Vest that appear to be similar may have a very different feel on your body.
  6. Angel- 1.58 is the diameter of many (CP and Tiffen) carbon fiber center/gimbal posts that I've been using for 30+ years... plenty strong and stiff enough for most work. Really long (superpost) center posts are probably somewhat better with a larger diameter center post, especially if the moves are violent. My 4 section Ultra 2 has a 1.58 centerpost for the gimbal, and two larger diameter posts going towards the battery and one inner, smaller diameter post going towards the camera. When compact, it's bulletproof. If fully extended to 6 feet – and the shot is pretty aggressive or rough – it helps to use tensioning cables to reduce the flex (it's part of the U2 design & the patent). The M2's 1.58 center post is plenty strong (I have a lot of experience with it). The 1.75 is stronger, of course, and comes with a 3 section option. I often worry that new operators (and some older ones) focus on one aspect, number, technique, etc., and don't consider it in light of many, many other important considerations of buying and using the gear. Especially in forums like this one, where an operator necessarily asks a question in isolation, simple answers often inflate both the importance of the question and any answer. It's why an intensive workshop is so important, where a broad spectrum of technical knowledge and operating wisdom is presented, and questions like center post size (an important question on its own) can be addressed and not blown out of proportion.
  7. In general, a larger centerpost diameter equates to a stiffer post, but that is not the only factor that determines stiffness. The inner diameter of that post, or wall thickness, also plays a part, as does the material – like different aluminum alloys. With carbon fiber centerposts, many other factors, including the weave, also come into play, creating more stiffness in some directions than others. And stiffness of the centerpost is only one of several factors in reducing or eliminating vibration in a sled. The weight of the camera & accessories play a huge role. What are you going to be carrying? Are you running? Doing slower moves in a studio? The “feel” of a larger centerpost is actually about the “feel” of the gimbal – its diameter and its knurling or operator added tape. With many gimbals, the gimbal’s diameter is much larger than the centerpost’s (like the PRO) or the same diameter, regardless of the centerpost diameter (M1/M2 for instance). Larger gimbal diameters give you more oomph (I’m being highly technical here, I know) on the sled, but it’s clearly too much for sleds with little inertia – hence the smaller control surfaces on the “little” Steadicams – like the Flyers and Aeros and the old JR. Centerpost diameter affects what is attached to it. Monitor rods of the standard 15mm on 60mm centers cannot clear a 2 inch centerpost. Although those rods could clear a 1.75 inch centerpost by .017 inches on each side, the strength of the mount would be compromised. The Tiffen monitor rods for the 1.75 inch centerpost are 15mm diameter on 100mm centers. While perhaps stiffer, there are three negative consequences of having wider monitor rods. One is that standard 15mm x 60mm c to c accessories – such as used on the rods from many stages for low mode monitors and MDR’s, can’t be used on the monitor rods. 2nd is that the monitor rods are wider right where your thighs are, so the sled must always be a tiny bit further away from you. And 3rd, bigger diameter centerposts and their gimbals, mounts and clamps weigh more than thinner ones. Maybe it’s not a big deal unless you are doing live TV, sports, or concert work where you are wearing the rig for a long time. So, IMHO, the question really should not be about centerpost size per se, but what system has the gimbal that feels right to you and a centerpost which has adequate stiffness for the jobs you do, and a system that doesn’t weigh more or take up more space than necessary.
  8. Peter Abraham sells a long dovetail plate of the smaller size for your Aero 30
  9. It has 3 separate HD video lines
  10. The G-50X will actually carry slightly more than 50 lbs. Does not get "weak" at all.
  11. More new things always coming... 1481875921_4Cablewranglers.pdf 1784752009_4Cablewranglers.pdf
  12. Always working on new things... these in response to customer's requests... Visit jerryholway.com for more 3D printed items. Stay safe everyone. 1384010595_Newstuff.pdf
  13. A custom spanner wrench for the top nut of the Master Series gimbal. It also fits the Ultra 1 gimbal. $50 includes shipping in the USA. The tight fit to the center post and the thickness of the wrench keeps the pins securely in the holes in the top nut. The wrench can be modified to fit other gimbals that do not have a "Blue Whale" tool. Other custom accessories available - see jerryholway.com
  14. I disagree. Keep the Volt. Practice like hell without it, but there is zero point in risking a minor horizon flub when on a real job. The point is to get the shot, and get it well. Who cares how on the day? It's your career and reputation for getting the shot, being efficient, artistic, pleasant to work with... and the Volt will only help you.
  15. Stiffness is a function of the OD of the material, and of the ID of the material, and of the material itself. With carbon fiber posts, there are a host of factors affecting stiffens, and stiffness can be quite different form one post to another, even if the first two factors (OD and ID) are identical. I'm sure any post that Greg makes (okay, and the M1 post) are super-stiff and won't give anyone any problems.
  16. Just a heads up: I haven't tried any of the aftermarket forks, but one should be aware that the Volt gimbal sizes and shapes are different. The fork anyone sells might work best for the M1/M2 gimbals and the modified M1/M2 gimbals, but work less well with the PRO modified or Shadow/U2/and Archer modified gimbals.
  17. One thing that needs to be said (repeatedly?) is that it is not just the post diameter that needs to be considered when adapting the Volt to other gimbals - there is a lot of engineering work in adapting the yoke and bearings and mounting of the motors. It's a lot easier to adapt the M1/M2 gimbals to post sizes less than 1.75 inches (with spacers). But for a post diameter larger than 1.75 inches, the gimbal must be modified. Companies must decide for themselves if it is worth it, as they are in business as much as we are.
  18. I keep adding parts to the catalogue as ops request them. The latest is a very small item that fits into Tiffen socket blocks to guide the arm smoothly into the block. I believe the original socket blocks from CP were machined with an internal taper (as are PRO socket blocks now, I think), but the newer blocks (say the last 30 years...) had a "well" between the large and smaller diameter holes in the block. Regardless, this part fills that gap and makes life easier. I've attached a PDF of almost everything I'm making now - this part is on page 24. Stay safe! 1402493684_3Dprintedacc.2_12.2021.pdf
  19. Charles- I don't think Arri has adapted their gimbal to the Volt. The M2 gimbal/Volt combination can come in a 1.750 post size, which will probably work with the Arri centerpost at 1.740 - I suggest you get a good set of calipers on the ARRI post and also communicate with the Tiffen factory to be sure everything will work out, or if Tiffen can make specific spacers to account for the .010 nominal difference in diameters. That should be possible.
  20. Here's a sample of some new things I've been making....(new stuff) and the complete list of all the parts I've been making 696551202_3Dprintedacc.1_16.2021.pdf New stuff 1.17.21.pdf
  21. I think post length should be altered to get the specific shot - either to change the lens height range and/or the rig's inertia. Choosing to configure your sled only one way is like playing 10 keys on the piano instead of all 88.
  22. mark- one of the design ideas with the Tiffen dock was to keep everything below the fork so that the Volt bits on the gimbal wouldn't be inadvertently hit and damaged. Using the Hill bracket with the Tiffen fork is possible, but there is more opportunity for accidental collisions.
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