Recreating a specific gear arrangement

[plastic-man]

I am completely new to the world of Lego Technic. And it seems that I have a lot to learn. Though I am learning as I go. I am planning to recreate a specific arrangement of gears as seen in this youtube video - 

 

What I'm trying to simulate starts at 2:20 in the video. Actually, the section I'm interested in runs from 2:20 - 6:40. I won't need the switches and it's not necessary to watch the whole video for what I want to do. I recognise the gears that are being used. To me, it looks like one worm gear, two 24 tooth gears and one 8 tooth gear. What I'm not certain about is the axle shafts. What lengths I would need. And whether I would need stops or pins on the shafts to keep the gears in place. Though I guess it's hard to recommend exact lengths for the axle shafts considering that my block arrangement may be a bit different to the one shown in the video. I guess it's safer to go a bit longer rather than ending up being too short. 

In order to get the correct spacing so that the gears are the correct distance from each other, is it necessary to use those white plates that are featured in the video? I don't suppose you could simply replace those plates with more blocks? Or maybe not as I notice when two plates are used together, the combined thickness seems to be a bit narrower than a block. At least it looks that way to me. The trouble is I am finding those types of plates to be very rare and hard to find. I have located these plates at this online store but I don't know if they're the same thickness as the ones in the video - https://dashbrick.com.au/products/lego-plate-1-x-8-light-grey-3460?pr_prod_strat=jac&pr_rec_id=d1e01829a&pr_rec_pid=6723857973283&pr_ref_pid=4810379722787&pr_seq=uniform

The 'output' in the video is a red and white object that rotates and ends up being connected to an arm. These two pieces will be replaced with a spool of string that will be connected to a camera and ball head on a home made camera slider. The camera and ball head together would likely weigh over 500 / 600 grams (or possibly a bit more.) As the spool rotates, the camera and ball head will be pulled along via the string for a video tracking shot. I need quite a slow speed for the camera movement. And obviously, I also need a lot of torque (for pulling all that weight.) From my research, Ive settled on a Power Functions XL motor. I did purchase an XL motor fairly recently along with a AA battery box. 

Edited 5 hours ago by plastic-man

[Stereo]

All genuine lego plates are the same thickness, shouldn't be hard to get them in general.

 

The triangle piece he mentioned can be built something like this; the dark grey piece 27940 is a common technic part and the only "new" thing I'm introducing here.  I used 7L axles (yellow) and a 5L with stop (brown) to make it easier to see the direction the axles are going, you could use any length 6 or more really.

 

If you're buying parts maybe look at 6588, it's a gearbox designed to hold worm gears - you slot the worm in, 24t gear in, and any length axles to reach your other mechanisms and it'll work.

[plastic-man]

Thank you! That's a great visualisation. Really puts everything into perspective. And I see that the triangular pieces are an alternative way of doing this. I would like to make my setup permanent so that I can travel around with it to different outdoor locations (where I'll be using the DIY camera slider.) Guess I'll have to decide which option would be more suitable as a permanent setup - the triangular pieces or the blocks and plates. I admit I have already bought some Technic blocks. 

The 6588 gearbox looks like a great apparatus. I could visualise that it would also support the 8 tooth gear with the same axle that's sticking through the first 24 tooth gear that's being driven by the worm gear. However, I guess I'd need something else to keep the second 24 tooth gear in place (if I use 6588)...perhaps some blocks and plates (or a triangular piece?)

Would I need stops on all the axles for the gears? I'm not sure if that's a stop I see up against the 24 tooth gear that's being driven by the worm gear in your visualisation.

 

Edited 1 hour ago by plastic-man