Arm Post
123 threads in the archive
AI draft, not reviewedDraft, written by AI from the archive, every statement linked to its source — not yet reviewed.
The arm post is the post your gimbal sits on, and it comes in three diameters, so check yours before you buy anything 18. Mixing makers or models usually means an adapter post or a machined reducer 26271920. Treat it as a load-bearing part, because posts, pins and mount bolts have snapped in the field 484950.
The questions 8
How do I set up a low mode bracket or pin on my arm?15 threads · latest 2023
In short
Pick a bracket that fits your post size, pin it through the gimbal handle, and check clearance in low mode 12. The international standard pin size is 5/8 inch 3.
How the pros do it
- Pick the bracket type first, because a bracket lets the camera sit lower and gives better arm-to-camera clearance than flying low mode without one 1. Keep a J-bracket to 6 to 8 inches, since longer ones interfere with your hand position 4.
- Match the pin diameter to your rig, since 5/8 inch is the standard and 1/2 inch is also in use 3.
- Pin it through the gimbal handle, and have the hole drilled on a mill, not freehand 2. Drill completely through for double shear, with 3/16 inch for a #10 hardened screw or quick pin 2. Do not rely on clamping or set screws alone 2.
- Check the orientation, so the gimbal arm stays in its normal upright position and not rotated 90 degrees 5. The flight pin holes on the bracket and the gimbal handle should line up parallel to their components 5.
- Check post retention by tightening the friction, and add a second collar or clamp below the lower bearing flange if the post slips 5. On an F-bracket, back up the set screws with threadlocker and a bolted metal collar 6.
- Check clearance in low mode, because the arm and post can hit the battery or camera on direction changes 7. A spacer bar moves the post away from the rig, and an angled bracket adds clearance 71.
Set screws alone can loosen in use and the whole rig and camera can fall 6. Long arm posts under heavy cameras flex and risk permanent post deformation or damaged arm bearings 4.
What changed
Earlier, in 2004, a J-bracket put the gimbal handle 6 to 12 inches lower 8, today, per 2009 threads, 6 to 8 inches is practical and posts over 12 inches are impractical because of flex 4.
My arm post is stiff or won't rotate freely - how do I fix it?13 threads · latest 2025
In short
Back off the post tension first, then clean and re-lube the bearings or fit thin Delrin washers 910. On an NB-Arm you can pull the post tensioner altogether 11.
How the pros do it
- Check the tension screw first, because on some arms a screw on the second post support controls post rotation and doesn't need to be fully tight 9. On an NB-Arm, operators remove the post tensioner entirely to get a free, loose post like a PRO-Arm 11.
- If your post runs on bearings and squeaks or drags, pull them and clean them thoroughly 12. Soak them in carburetor cleaner, dry them with compressed air, then lube with Triflow or skate bearing speed cream 10.
- On the GPI Titan Arm the bearing covers come off one side with a small pointed tool 10. A slightly oversized post can make the bearings stiff, so check the post diameter 10.
- If the post sticks in the gimbal, use a post collar with a Delrin washer instead of locking the post directly on the arm 13. Delrin or Teflon washers thinner than 1/16 inch reduce friction better than thrust bearings 14.
- For replacement discs, thrust washers with a 5/8 inch bore work, and McMaster-Carr and IGUS stock Delrin, nylon and self-lubricating plastic washers 15. Measure before you order, because nobody confirmed these as exact matches 15.
- Look at the surfaces too, since irregularities on the post or gimbal interior cause binding and light sanding or emery cloth can fix them 14. Keep the hard anodizing, because sanding it off exposes soft aluminum that galls more easily 14.
Thrust bearings that are too thick create stress concentrations that can cause handle failure where the post clamps, mainly on older split-clamp gimbals 14. Lateral stresses on the thin top connection of a DIY frictionless post setup are also a concern 17.
Opinions differ here
Some operators lock the arm post to cut down on constant hand adjustment and keep the rig stable 16. Others run it with minimal or no friction and say the handle stays put when the rig is balanced 16. Longer gimbal arm lengths may make tighter post friction more practical for running shots 16.
What changed
Earlier, in 2007, thrust bearings were called too thick for arm post and gimbal handle connections, while today, in 2014, thrust washers with a 5/8 inch bore are suggested as smooth replacements for Delrin discs 1415.
What arm post diameter does my gimbal use, and how do I adapt sizes?13 threads · latest 2024
In short
Gimbals use three arm post sizes: about 0.740 inch on Master, Ultra, Shadow and M1, about 0.621 to 0.623 inch on 3A, PRO ARM, Titan, Atlas and X1, and about 0.493 to 0.495 inch on Flyer, Pilot, Archer and ProVid 18. To mix sizes, use a dedicated adapter post or a machined reducer 1920.
How the pros do it
- Look up your gimbal in the size groups above and don't confuse arm post with centre post 1821. The 3/3a has a 1.5 inch centre post with a 5/8 inch arm post, while Master and Ultra have a 1.58 inch centre post with a 3/4 inch arm post 21.
- Treat the sizes as nominal, because tolerance is built into either the post or the gimbal handle 18. PRO arm posts tend to run undersized so they slide into the handle easily 18.
- For a Master/Ultra gimbal on an EFP/3A/PRO arm, Tiffen makes adapter post 250-7975 at $175, and it only works in one direction 22. For a G-70 arm on a 5/8 inch gimbal, Tiffen lists 800-7204-03, but its post length may be too short for a VZ Pro 23.
- With a G70X arm, pick a 6 inch G70X arm post with a 5/8 inch top for Artemis-type gimbals, or one with a 1/2 inch top for Zephyr-type gimbals 24.
- If nothing off the shelf fits, a machinist can make a reducer bushing, for example to take an M1 handle down to 5/8 inch 20. The Master/Ultra size bore spec is 0.740 inch, plus 0.000 and minus 0.002, after anodizing 22.
- One instructor's rule of thumb is no more than about 7 inches under typical working conditions, and your limit depends on material, load and mode 25.
A cracked arm collar can fail suddenly under load 19. Gaffer tape alone can't make up a post diameter difference because the torque is too high 19.
What changed
Earlier, in 2007, operators talked only about 5/8 and 3/4 inch posts 19, today, in 2018 and 2024, the sizes are given as about 0.740, about 0.62 and about 0.49 inch, with the small post at 0.492 rather than the nominal 7/16 1825.
Can I mix arms, sleds and vests from different Steadicam® models or brands?13 threads · latest 2022
In short
Yes, mostly, but the arm post is where it gets tricky because diameters differ between makers, so you often need an adapter 2627. Keep Pilot-family arms and vests with the Pilot sled 28.
How the pros do it
- Check the post diameter first, because it is not standardized: 1.5 inch pro standard, 1.58 Tiffen, 2 inch XCS, 1.75 inch on some Glidecam models 26. A 1.75 inch post limits you to that maker's own gimbal and monitor mount 26.
- Mating a PRO arm to a Tiffen Ultra2 sled needs an adapter, because the PRO post is 0.625 and the Ultra2 gimbal handle socket takes 0.740 27. Buy the adapter post, have one machined, or use a thin-walled sleeve held with adhesive or thread-locking compound 27.
- For a GPI Pro Titan arm on a Steadicam® Ultra2 sled, you need an arm post adapter, and Tiffen distributes the parts 29. The manufacturer can also make custom adapters on request 29.
- On vests, PRO and Tiffen socket blocks can be swapped because they share the same hole pattern and screws 27. The PRO vest has an undersized socket block that can cause fit problems with Tiffen and other arms 27.
- A modified Flyer arm can run on full-size vests and sleds with a conversion kit and a male socket block, which you source separately 30. The change is reversible in about five minutes 30.
- Keep the Pilot arm and vest with the Pilot sled, because the post geometry differs from other models like the Merlin 28. Pilot, Zephyr and Flyer share the same docking bracket thanks to identical arm post sizing 31.
If you push a bigger arm onto a smaller rig to carry more weight, overloading can damage the gimbal, gimbal yoke or stage-to-post junction 34. A longer arm post to balance the load can also introduce vibration 34.
Opinions differ here
One 2010 thread says mixing brands is problematic because post diameters and socket block tolerances vary, for example a Glidecam vest on a Steadicam® arm 26. A 2013 thread says most top-tier components from different makers mix without significant technical problems, and that vest choice affects feel the most 33. Both agree that buying used and mixing by compatibility and budget is a sensible route 2633.
What changed
Earlier, in 2006, you fitted bronze bushings to the Flyer arm post to match a standard 5/8" sled post hole 32, today, as of 2012, a reversible kit converts a Flyer arm to standard posts and male socket blocks in about five minutes 30.
Which arm should I choose for my camera's weight?11 threads · latest 2026
In short
Pick the arm whose load range covers your camera and sled, and don't push the rig past its rating 35. A G50x arm with the M2 handled 30-40 pound cameras in workshop training 36.
How the pros do it
- For a very light sled, check the arm's minimum, because the PRO arm needs a sled of at least 13 lbs and the NB arm has no minimum 37.
- For a wide load range, look at the XARM, which ships with three spring cores covering up to 29 kg 38. Cores swap in under two minutes without tools, and optional cores for lighter rigs start at 8 kg 38.
- Size the arm post to the arm and the load, since a G50 arm on a Zephyr needs a larger socket block and a properly sized post 34. A longer post to balance an overweight load can bring vibration, and dual battery plates low on the rig reduce the post length you need 34.
- On a Tango the payload drops as the arm gets longer, roughly 10 pounds at the shortest setting, 8 at mid-length and 6 at full extension 39.
- Match the vest to the load too, because a Zephyr vest flexes noticeably near 20 pounds and heavier cameras call for a larger rig vest 36. Very heavy setups like an Alexa 65 would strain a G50x 36.
Overloading a rig can damage the gimbal, gimbal yoke or stage-to-post junction 34. On compact sleds like the Archer 2 it can cause gimbal failure or bearing wear that needs repair or replacement 35.
Opinions differ here
Band arms are contested 41. One G70x operator calls the Rocket Arm the best arm he has tested, with no perceptible friction and about 5 lb less weight 41. The NB-Arm manufacturer asserts that Rocket Engineering copied its design features, and one operator still prefers the NB-Arm 41.
What changed
Earlier in 2004 the SK2 topped out at 19-20 pounds 40, today in 2022 a G50x arm with the M2 handles 30-40 pound cameras 36.
How do I extend my arm post for tall subjects or extreme angles?8 threads · latest 2021
In short
Swap in a longer purpose-built arm post, but keep it around 12 inches on 5/8-inch pins 42. For more height, use a mid-arm swivel or raise the arm connection on your vest 4342.
How the pros do it
- Swap the post for a longer one from the rig manufacturer 42. On some arms you unscrew the post from the bottom, and posts run from 6 to 18 inches 44.
- Posts longer than that on 5/8-inch pins are considered unsafe 42, and posts over twelve inches may bring fatigue 45.
- It moves the camera up to 12 inches above or below standard with 2.8, 6 or 12-inch posts, each swap takes 15 seconds to a minute, and it only fits the Pro arm for now 43.
- A GPI PRO Arm with a mid-arm swivel from another manufacturer adds about 14 inches of height, roughly 26 inches above standard in total 42.
- Vests like Exovest, xSPINE and Klassen have height-adjustable front mounts 42, and raising the socket block gives extra height if the post can't change 46.
- Don't boom the arm all the way up, because it absorbs vibration worse there 46. In rehearsal, boom fully up and adjust the top stage until the arm needs little or no hand pressure to hold height 46.
Arm posts longer than about 12 inches on 5/8-inch pins are considered unsafe 42. Makeshift threaded-rod extensions only suit lighter payloads, and purpose-built posts are safer 44.
Opinions differ here
Operators don't agree on how far a longer post can go 434244. One source says lifting the camera 5 or more inches with a longer post can bend or break the arm 43, another puts the safe limit at about 12 inches on 5/8-inch pins 42, and another lists posts up to 18 inches but flags safety concerns 44.
What changed
Earlier, in 2004, operators ran hollow aluminum posts to about 8-10 inches and stainless posts at 12 inches 47, today, in 2021, about 12 inches on 5/8-inch pins is the limit and swivels or vest mounts cover extra height 42.
Can my arm post, pins or mounting bolts break under load?8 threads · latest 2010
In short
Yes. A backpack mount bolt snapped during a relaxed swing of the rig 48, a G-50 post pin snapped in use 49, and an arm post broke from metal fatigue on a 35mm film job 50.
How the pros do it
- Don't trust set screws alone on the F-bracket, because they can loosen and drop the whole rig and camera 6. Bolt a metal collar onto the post as backup, put threadlocker on the set screws and check them regularly 6.
- On a G-50, know that early units had an internal arm post pin that could snap with a loud crack 49. Tiffen retrofitted thicker pins free, but if you bought around 2006 your dealer may have missed you 49.
- If the threads in a G-70 arm top part strip, a longer screw of the same diameter and pitch may reach undamaged threads deeper in the hole 51. Call customer service for the right screws or to find out whether the part needs replacing 51.
- Check the metal docking cord on a G-50 arm, because several users had it break 52. Replacement cords with the changed design have shown no failures since 52.
- On a backpack mount, a custom fixed adapter can replace the adjustable bolts if you don't need the flexibility 48. One adjustable bolt snapped on a relaxed swing, and the replacement bearings were hard to source 48.
- Keep the camera well inside the rig's limits, because an Aaton 35-III pushed past them and the arm post broke on the actual take after several rehearsals 50. Fatigue can catch you even if you've flown heavier cameras on that rig before 50.
A loose F-bracket can drop the whole rig and camera 6. A broken docking cord is a hazard if the arm falls while resting on the bracket 52.
What changed
Earlier, in 2008, early G-50 arms had a thin internal post pin that could snap 49, today a thicker post and a quick-release interchangeable post on the Clipper series are available 53.
How should I set my socket block and arm height for my body?5 threads · latest 2026
In short
Check your torso-to-leg proportions first, then pick a post that puts the camera at eye level 5455. Fit the vest, zero the socket block screws and balance the sled with your hands open 56.
How the pros do it
- Divide your height in half and compare it to the distance from the widest point of your hip to the floor, which should be roughly equal 54. If your torso is long for your legs, expect to need the socket block higher on the spar and a longer arm post even at standard heights 54.
- One operator used a 12-inch arm post to put the camera at eye level and keep the arm neutral 55. That spread the weight higher on the body instead of straining the legs and lower back 55.
- Fit the vest snug on your shoulders with even velcro tension on both sides and sitting straight 56. Center the waist portion vertically on your pelvic bones 56.
- Zero the socket block: turn the bottom knurled screw all the way in, then out a quarter turn so it doesn't bind 56. Turn the top knurled screw all the way in, then out two and a half thumb-turns as a starting point 56.
- Stand with good posture, turn your pelvis 45 degrees toward the sled and gently open your hands 56. If the sled falls away from you, move the top thumb screw in and the bottom one out, and reverse that if it falls toward you 56. Adjust side-to-side only with the top knurled screw, keep everything finger-tight, and keep the bottom knurled screw as tight as possible 56.
- If you need the arm lower, a vest drop moves the whole boom window down but costs you the same amount at the top 57. Trimming plastic from the waist panel lowers the block about a quarter inch on an Ultra 2, and a post only about one inch longer may be acceptable, but don't go longer with heavy camera loads 58.
What changed
Earlier, in 2008, operators lowered the socket block by modifying the vest, for example trimming about a quarter inch of plastic from the waist panel 58, while today, in 2026, they use a two or three inch vest drop that shifts the boom window down 57.
Sources 58
- 1Operating Steadicam® in low mode with and without a D/F/J bracket
- 2Drilling a hole in a gimbal handle to accommodate a low mode bracket pin
- 3Sourcing arm pin offset brackets and understanding pin diameter standards for inverted or low-mode operation.
- 4Flexing and practical use of J-brackets on steadicam arms with various post lengths and payloads
- 5PRO Titan arm low mode bracket orientation and arm post retention solutions
- 6Securing camera support brackets and safe docking practices for stabilized rigs
- 7Low mode operation challenges and solutions for steadicam rigs
- 8Comparison of D-Bracket and J-Bracket designs for gimbal camera rigs
All 58 sources
- 9Stiffness at the connection between arm post and gimbal on steadicam arms
- 10Maintenance and lubrication of post bearings in GPI Titan Arm
- 11Removing the post tensioner from an NB-Arm to replicate PRO-Arm feel for operators switching models.
- 12Restoring smooth rotation to a squeaking arm post with bearings
- 13Aluminum arm post sticking in gimbal socket due to friction
- 14Reducing friction between arm posts and gimbal handles using bearings and washers
- 15Finding replacement delrin or plastic discs for arm post clamps to reduce friction during gimbal arm movement
- 16Arm post friction adjustment and its effect on operating stabilityDisputed
- 17Creating a low-friction post clamp for IIIA arm posts
- 18Arm post sizes and compatibility across different gimbal and arm models
- 19Adapting camera arms with different post sizes to prevent play and handle torque issues
- 20Adapting M1 gimbal handle to accept 5/8 inch arm posts instead of the standard 3/4 inch
- 21Steadicam® centre post and arm post diameter specifications across different models
- 22Arm post adapters for connecting incompatible gimbal and arm systems
- 23Adapter compatibility between Tiffen G-70 arm and VZ Pro gimbal
- 24G70X arm post adapters for different sled gimbal sizes
- 25Low-mode angled bracket with reducer post for G50X arm post: specifications and load limits.
- 26Compatibility of mixing Steadicam® and Glidecam components in a stabilizer rig
- 27Compatibility between PRO arm stabilizer and Tiffen Ultra2 vest and sled
- 28Choosing between complete Pilot steadicam system versus sled-only with aftermarket arm and vest components
- 29Combining GPI Pro Titan arm with Steadicam® Ultra2 sled
- 30Modification kit to adapt lightweight camera arms to standard-size vests and sleds
- 31Docking bracket compatibility across Scout and similar models
- 32Combining a MK-V Lite sled with a Flyer arm and alternative vests
- 33Mixing different brands of stabilizer components when building a first rig
- 34Using a larger steadicam arm to exceed weight capacity of a Zephyr rig
- 35Payload capacity differences between steadicam sleds and how it affects equipment selection
- 36Starting steadicam work with M2 package: arm, post, and vest capacity for various camera types
- 37Comparison of NB arm with PRO arm for steadicam work
- 38Flowcine XARM camera crane system specifications, performance, and compatibility
- 39Tango telescoping arm specifications, weight capacity, and camera/lens compatibility for Steadicam® use
- 40Choosing and upgrading a Steadicam® rig for beginners with lightweight cameras
- 41Rocket Arm (elastic band arm) versus traditional spring arms like the G70x: performance, weight, build, and design dispute.Disputed
- 42Achieving greater lens height for tall performers: arm post length and vest-mounted swivel options with 5/8-inch pins.
- 43Extendable mid-arm swivel for steadicam to achieve extreme high and low camera angles without extending the center post
- 44Extending arm posts on steadicam rigs for shorter operators
- 45Trade-offs between extending telescoping posts for longer rigs versus keeping camera stabilizers compactDisputed
- 46Techniques for operating a camera rig when filming a person who is significantly taller than the operator
- 47Riser handles as intermediate pieces between arm and sled to raise sled heightDisputed
- 48Failure of adjustable bolts in backpack mount socket block during normal operation
- 49G-50 arm post pin failures and available upgrades
- 50Steadicam® weight limits and arm structural failure when operating 35mm film cameras
- 51Stripped threads in G-70 arm top part attachment point
- 52Metal cord on G-50 arm docking bracket breaking during use
- 53Replacing the top post assembly on a Tiffen G-50 camera arm
- 54How torso-to-leg proportions affect socket block positioning and arm post selection
- 55Steadicam® techniques and equipment choices for a complex opening shot involving stairs and backwards movement
- 56Adjusting Steadicam® arm and vest socket block settings for proper balance and body alignment
- 57Vest drops: what lowering the arm socket actually buys, and what it costs at the top
- 58Modifying the Ultra 2 vest to lower the socket block position for improved comfort and ergonomicsDisputed
What operators found
- One experienced G70x operator reports the Rocket Arm as the best arm tested: smooth, compliant, without spring effect, no perceptible friction, and completely silent.2026 FacebookDisputed
- A vest drop moves the arm's socket block down the vest. It does not extend the arm and it does not add range. It shifts the whole boom window downwards, which is why it is reached for by shorter operators and by anyone who spends the day in low mode.2026 Operator practice
- Useful accessories include SOS plate, long plate, Hill EVF bracket, rain covers, power cables with battery eliminator plates for powering cameras, long arm post, J bracket, and wind killer2026 Steadi-Newbies
- Operators transitioning from a PRO-Arm to an NB-Arm can remove the post tensioner entirely, allowing the arm post to rotate freely and loosely as on the PRO-Arm.2025 Facebook
- The M-2 gimbal offers adjustable arm post diameter through factory-installed sleeves, while the M-1 requires replacing the entire handle to change arm post sizes.2025 General Discussion
- Precise arm post diameters are 0.740 inch and 0.492 inch, not the nominal 3/4 and 7/16 inch.2024 Facebook
Still argued about
- 2026Rocket Arm (elastic band arm) versus traditional spring arms like the G70x: performance, weight, build, and design dispute.FacebookThe Steadicam Group
- 2021Steadicam® Zephyr with Panasonic VariCam LT: weight management, gimbal stress, and configuration to prevent breakage.FacebookSteadicam operators group
- 2021Trade-offs between extending telescoping posts for longer rigs versus keeping camera stabilizers compactSteadi-Newbies
Often in the same threads
Low Mode19, Top Stage11, Volt6, G-70X4, NB Stabilizer Arm3, Gimbal Bearing3, G-7017, Zephyr14, Master Series10, Artemis4, Dovetail Plate4, Docking Bracket4
All threads
- 2026Rocket Arm (elastic band arm) versus traditional spring arms like the G70x: performance, weight, build, and design dispute.DisputedFacebookThe Steadicam Group
- 2026Vest drops: what lowering the arm socket actually buys, and what it costs at the topOperator practice
- 2026Recommended upgrade priorities for a GPI Pro steadicam rigSteadi-Newbies
- 2025Removing the post tensioner from an NB-Arm to replicate PRO-Arm feel for operators switching models.FacebookThe Steadicam Group
- 2025Differences between M-1 and M-2 gimbal designsGeneral Discussion
- 2024Low-mode angled bracket with reducer post for G50X arm post: specifications and load limits.FacebookThe Steadicam Group
- 2023Hanging a Tiffen G50X arm on a docking mount pin without a harness; availability of longer arm posts.FacebookThe Steadicam Group
- 2022Sourcing arm pin offset brackets and understanding pin diameter standards for inverted or low-mode operation.FacebookSteadicam operators group
- 2022Measuring the depth of the Steadicam® Zephyr gimbal handle bore for the arm post.FacebookThe Steadicam Group
- 2022Maintenance and lubrication of post bearings in GPI Titan ArmArms
- 2021Steadicam® Zephyr with Panasonic VariCam LT: weight management, gimbal stress, and configuration to prevent breakage.DisputedFacebookSteadicam operators group
- 2021Achieving greater lens height for tall performers: arm post length and vest-mounted swivel options with 5/8-inch pins.FacebookThe Steadicam Group
- 2021Comparison of NB arm with PRO arm for steadicam workArms
- 2021I-Baird 2-inch versus 4-inch adapter selection for vest compatibility with operator height and boom rangeVests
- 2021Trade-offs between extending telescoping posts for longer rigs versus keeping camera stabilizers compactDisputedSteadi-Newbies
- 2021Extending arm posts on steadicam rigs for shorter operatorsSteadi-Newbies
- 2020Extending arm post length on Scout camera support systemArms
- 2019Configuration of canisters on a Titan arm with fewer than four unitsArms
- 2019Using a larger steadicam arm to exceed weight capacity of a Zephyr rigGeneral Discussion
- 2019Tiffen M2 steadicam sled specifications and featuresGeneral Discussion