need advice on source for gears and/or the best forum

[JimFromLA]

Honestly, I'm not into robotic anything. I'm hoping that someone here can advise me how best to obtain some gears for my (non-robotic) application. Additionally, I have no significant background in gears.

Here's the plan. I'd like to build a cabinet with two doors. When I pull/push on one door, the other door will open/close in kind. I think I can achieve this by utilizing bevel gears or worm gears. I assume that gears have a "handedness" or rotation component to them (i.e. right-handed, left-handed or clockwise/counter-clockwise). Correct?. So I need a matched pair. The application involves very little weight or stress. I'd actually prefer them to be made of plastic as the cabinet will be in a humid environment.

If anyone can point me in the right direction, it would be very much appreciated. There even may be a six-pack in it for the winning answer!

Seriously though, thanks,
Jim

[BeligerAnt]

All you need is a flat gear train with an even number of gears. The first gear rotates with one door, and the last one rotates with the other door. Since alternate gears rotate in opposite directions, when the left door opens and its gear turns clockwise (when viewed from the top), the last gear will turn anticlockwise causing the right door to open.

Simple gears run equally well in both directions, you don't need to worry about "handedness".

To save having a long gear train, you may be better off with a belt/chain, although a belt doesn't provide the reversal of direction so you would need one stage of gearing at one end.

Hope this helps

[daliad100]

With the loading required you could quite possibly get away with only using a pulley type mechanism.

Consider a reversing belt drive (180 degree twist in the belt). Stick the pulleys on the hinge axis of your door and then permanently attach the rope/belt/chain to the pulley. When you open either door one rope will pull the other open and when you close either door the opposite rope will pull it closed.

Proper pulleys aren't even needed, just two pieces of rope the correct length and some material to make some semi circles with if you want to improve force transfer and make the doors easier to open.