Hello, I am attempting to obtain a 5000:1 Gear reduction ratio. I'm looking at using worm gear reducers. To give you a sens of scale, I am attempting to spin a bicycle wheel at an ultra slow speed (0.001mm). The Motor I have has a torque of 0.5NM - 7.4NM However, I am a total noob when it comes to gearing and setting it all up. I have a very high budget and I only access to the products listed at http://www.sdp-si.com/web/html/products.htm. Any help would be appreciated. I was actually looking at using their prebuilt speed reducers but I don't think you can put them in series as their max input torque is much lower than their output torque causing failure(?). Thanks a bunch.

I love people with very high budget. Let us be friends Tell me please your needed angular velocity at revolution per minute. (speed is very, very different) The motors that you describe have really HIGH torque. You don't need this torque because you will soon be wondering how do dissipate the heat they produce. With reduction of 5000:1 reduce 5000 rpm into 1 rpm and you turn 1 Nm into 5000 Nm. This is more that a truck engine is capable of. The torque at the end is to be considered ONLY if it is applied. If you do not apply any torque at the end the total work is near zero. You can try a planet gear. If you really want to apply 5000 Nm at the end you will not succeed with this website. If you need some help - feel free. Source

I have quite a bit of experience with gear sets and Stock Drive Products. The basics of your problem fall into two variables: torque and speed. If you have no real desired output torque level (nothing being driven) and you are only looking to achieve a specific speed, then you can combine just about any set of gearboxes together, being mindful of speed limitations. Gearboxes typically have an input speed limit due to their construction. Lower input speed limits means there is more use of plastics or journal bearings. But with no real limit to your budget you should be able to find a higher quality gearbox that is of all metal construction with ball bearings, which are typically able to handle higher torques and speeds. However if you can't find a gearbox that will work SDP has plenty of gears to pick from to make your own first stage planetary reduction. With a large ring gear (internal gear) and a small sun gear, you could get an initial reduction of around 20:1, bringing your overall reduction down to a much more manageable 250. (I saw a 260:1 gearbox on SDP). The tough thing is going to be the engineering in the design of the initial reduction stage. I'd be happy to help you out more if you need it, send me a message. Source