Compound Gear Ratio Project HELP ASAP

Hello all,

I need your help with this project Im doing. It has to do with “compound gear ratio”. We have to build this lego set only using “fischertechnik build kits”. Since Im the only one in my class who doesn’t have a group neither a partner. I need as much support as I can from you guys. And also will be attached my project description. Please look it over and tell me what I can do. I appreciate everyone for helping me out.

Compound Gear Project Description.pdf (71.2 KB)

Here’s a link to a gear ratio lesson that will help:

What are the gear options in the fischertechnik build kits? How many teeth are on each gear.


Thanks for Replying. The teeth gear are 12, 30, 48, and 60 from what I know. I have to get the gear ratio to be close as 1:100.

So what are the possible gear ratios we can get out of those gears?

Also what is the prime factorization of 100, just to give you something to think about?

I do not know what you mean by the possible gear ratio but, the prime numbers that make up a 100 is 2 and 5 right?

So every possible gear ratio would be
12/30 12/ 48 12/60
30/12 30/48 30/60
48/12 48/30 48/60
60/12 60/30 60/48

That’s every possible combination of gears. And we know from the prime factorization that to get to 100 we need 2,2,5,5.


Ok ok now I get what you mean.

@tabor473 ill leave you up to this one :slight_smile:

Theres a gear calculator spreadsheet by VEXPro, use it if youre struggling to find the perfect ratio