You can choose any metal for the parts, since weight gain is only beneficial. The main thing is to ensure the rigidity of the structure. Weights should not swing the horizontal bar, and the vertical bar should provide sufficient resistance to bending and torsion in order to avoid the occurrence of spurious damped oscillations.
When testing the layout, I used a thin-walled steel channel as a vertical bar which just had low torsion resistance, which led to the occurrence of spurious camera vibrations in the horizontal plane.
For reliable fastening of the handles, holes were drilled in them, into which metal threaded bushings were glued using epoxy glue.
Here is the inertial stabilizer with the camera installed in assembled form.
In order not to take the weights on a trip, it was decided to replace them with rigid 250 gram PET bottles filled with sand. The specific gravity of sand in the reference book is about 2.7gr / cm³. In this case, the mass of each of the weights should be equal to about 700g. Such a mass and its distribution map should provide stabilization no worse than when using a full-sized stabilizer.
I must say that during freefly movi review with river sand, it turned out that the weight of the filled bottles reached only 1.2 kg. However, due to the shape of the bottles, the quality of stabilization was not worse than the one provided by a full-size device.
To ensure the necessary rigidity of the structure, it is advisable to choose the most dense thick-walled bottles, with caps with a diameter of at least 40 mm. It should be noted that the bottle labels made of heat-shrink film give the bottles extra rigidity. Such labels should not be removed.
Washers covering covers on both sides should be as large as possible.
In order for the screw fixing the square to the horizontal bar of the stabilizer not to scroll in the axle box while tightening the lamb, the contact surfaces of the axle box and screw were tinned, and the screw was tightened in the axle box in a heated state.
The increase in the number of parts of this unit is due to the absence of large washers with a small diameter of the inner hole.
And this is the “beach version” of the stabilizer when assembled.
In order that the stabilizer can be installed on a horizontal surface between shootings, a square “window ” is added to the mount of one of the bottles.
The disadvantage of this stabilizer is that it attracts excessive attention from others. The attempt to put black socks on the bottles did not give much effect. Apparently, the unusual shape of the device really does attract much attention.
Attention! In all the drawings, conventional and roving washers are not shown, which are preferably used when assembling and locking the fasteners. Lock screws with countersunk heads can be nitro paint or nail polish.
The size ratio of the inertial stabilizer
When the camera deviates from the horizontal axis, the videographer is forced to fix the stabilizer handle in his hand. The moment of force transmitted to the person’s hand is directly proportional to the length of the vertical bar and the weight of the camera, and inversely proportional to the diameter of the handle. Therefore, the convenience of controlling the camera depends on the diameter of the handle. To improve tactile sensations about the position of the handle in the hand, it is useful to make small concentric recesses on it.
The thinner the handle, the harder it is to stabilize the steadicos during acceleration, but the thicker the handle, the weaker the tactile sense of the horizon.
Another compromise is the choice between the size and weight parameters of the design and the quality of stabilization. The longer the horizontal bar and the heavier the weights at its ends, the higher the quality of stabilization. However, with an increase in the length of the horizontal bar, its end may fall into the field of view of the lens, and an increase in weight makes carrying equipment uncomfortable. I do not recommend increasing the weight of the equipped stabilizer to more than 2.5 kg, and it is better to adjust the size limit to your favorite camera case.
Adjustment of the inertial image stabilizer for the camera
If you use weights, the position of the center of gravity of which cannot be changed (as in the photo), you can adjust the horizon by turning the vertical bar a small angle in its mount. Before adjustment, one of the screws is released, and the second one is not completely tightened. After that, the bar is set to the desired position, and both screws are tightened.
If the camera does not have an electronic level indicator, then an external bubble level can be used to adjust the horizontal position of the camera.
If you refuse to install a quick-detachable platform, and use a standard photo screw, then such a stabilizer can be made in just a couple of hours.
Here is the idea of how you can raise the photo screw from the flash above the horizontal bar.
How to use an inertial stabilizer
As it turned out, using an inertial stabilizer is much easier than traditional steadicam. The rigid inertial stabilizer is always instantly ready for operation, due to the absence of damped oscillations inherent to the pendulum type steadicam.
When picking up speed, it’s enough to firmly squeeze the handle of the device and loosen the grip as soon as the speed stabilizes and the trajectory becomes straight.
The weight of the balancing structure in the hand makes it easy to feel the position of the camera relative to the horizon through tactile sensations. To improve tactile sensations, the handle is removed from the center of gravity of the system at a greater distance than in professional video cameras.
The disadvantages of the inertial stabilizer of the presented design
The main disadvantage of this homemade device is the significant weight that you have to hold in one hand when shooting and carry on the shoulder during transportation. It’s true though that steadicams of other types also have these shortcomings.
The use of a stabilizer for special effects
If you install one of the stabilizer handles at the camera level and remove the weights, you can (when shooting with your hands) create the special effect of “swing” or “ship pitching”.
In order for the loops intended for fastening the belt not to interfere with sound recording during rotation or sudden movement of the camera, they can be fixed with a clerical gum.