Im just starting to build some kind of re-usable "stage" for my upcoming stop motion masterpieces. Im probably going to get into the whole Moco question, with stepper motors and arduinos and sliders etc.
Right now I have a slider, mounted on tripods, a few good lights... and...
An old table that I think would make the basis for a good "stage".
Before I jump right in Id like to ask a fw very simple questions to save me the heartache of finding out the long way. Hope you guys can oblige with your experience.
1) What is a good working height? Currently the table is just 40cms high and I was thing to increase it to about 1m, or 90cms. Assuming I will be sitting here for many hours leaning in and out, what would be a good ergonomic hight?
2)I have variable colour on my lights, and I may get arty (probably actually) with gels etc, but would you normally shoot tungsten or daylight colour?
3)Assuming I only have a regular slider for left/right moves, Are there any cool ways to track in and out (In the old days I used to move the whole scene (on squared paper to time to moves) towards the camera, but that was completely wrong really as the lights didnt move, so shadows would move... I didn't notice it much then, but I do now. Im think of making sliders on each side of my table that the camera slider can move on... Is this a known way? How DO you do tracks?
Im sure there will be many more questions... but maybe...
Can I ask?
Can you guys share pics of your stages, if they seem relevant to what IM try to achieve.
Maybe I can make a "build series" ? so here's my starting place...
Can I ask, did you buy the cogs someplace? I feel I can probably make a few custom bits, buy a few brackets and camera mount parts, but the cogs and bearings Im not so sure about. Did you copy/follow a particular design, or just design from scratch on paper?
Personally, Im pretty good and making things (im am animator, its 80% of the job) but lack the metal working tools, so am kind of looking out for parts I can re-purpose. Like pan tilt heads that can be hacked to be motorises etc,...
Yes, the gears and bearings came from Servocity. If you are in the UK, they are distributed by Active Robots.
I took the same approach as you, and found I was able to source quite a lot of parts. For example, the camera mount is a Fotomate 3 (the long one) with an extra Fotomate slider mounted on it. The right angle camera platform is Arca-Swiss or similar. I have made a new, more geared down focus controller using a manual focus controller as sold for camera rigs.
I will be taking a slightly different approach for the next rig, partly as I have bought a 3D printer. So the only stepper motors that have sufficiently small backlash are the high precision ones, and you need something like 30:1 reduction on most of the axes. My new approach will be to see if I can achieve this with worm gears, as there is minimal backlash and the advantage that the gears will prevent anything moving even when the power is off. Servocity sell some nice looking worm gears.
If going down the conventional route, the gears I used were 100T servocity ones with 1" bore, driven by 30T gears on the motor (which was already geared down). I also make sure that micro-stepping is enabled on the drivers... but that's another whole ballpark. The 1" bearings and shafts from Servocity I rate highly, because a larger diameter gives greater accuracy and they have fantastic pillow blocks for mounting. You can also get an Aviation connector through the tube.
I recommend going for the Aviation connectors, and you will need quite a lot. The 4 pin version is what you need. I sourced wire cable from car suppliers.
For the track, my big rig used an aluminium ladder, and it works very well. On that I ran some scooter wheels, but we needed to remove the rubber tyres, so they are not perfect. There are some nice nylon ones available now. My track was 2m long (!), and I will be going for something just 1m long next time. You need ball bearings on everything that moves.
On top of the track is a large square dolly with two plastic discs, one attached to the dolly, one to the tower. These have 14mm ball bearings running between them, held captive by an mdf ball cage. There is a 6mm pin running in a bearing in the middle. It swings round effortlessly.
The tower was constructed from birch ply and has a thrust bearing at the top onto which the jib arm goes. The jib arm is controlled by a ballscrew operated by a motor attached to the tower. It works very nicely, better than Edu Puertas's revised arrangement for his rig, as it does not stick out but up.
At the end of the jib arm is the pan/tilt head, which you have seen pics of.
The electronics are controlled by an Arduino Mega 2560 with black box drivers, which I consider to be the best arrangement as they are optically isolated and you can easily select micro-stepping without fiddling around with bridges etc, I also have an Arduino Uno with CNC shield, ut have not got this working yet. I made the mistake of just using the sketch provided by DF, and it blew the Arduino. There is a thread on their forum about adapting a sketch for the CNC shield.
The smaller rig runs on a track made from 2 stainless tubes, with ball bearings on the dolly. The tubes are 200mm apart, as I consider the normal camera sliders that people adapt to have too narrow a footprint to be stable. The 3D printer will enable me to make new end pieces and utilise some 40/40 extrusions for maximum stability. I will keep to this width.
The small dolly track is belt driven, and I would consider using belts instead of gears next time. With either you have to have a tensioning mechanism or a means of meshing the gears closely so there is minimal backlash - that is your enemy, so precision everywhere is essential!
Hope this helps!