regarding gear ratios and their matings

chand_basha

Hi,
      I have created an epicyclic gear assembly with 1: 0.5 ratio (from sun to ring) in which carrier is fixed. that time the gears are mating properly. and after that, I changed that ratio to 1:0.333 by adjusting no fo teeth on gears. now I am not getting proper mating b/w gears. I followed all the formulas like   Tr=Ts+2*Tp and Rr=Rs+2*Rp even though I am not getting it please somebody help me. 
  
 here are the links:
 for 1:0.5 the link is 
https://cad.onshape.com/documents/933b7b93dcd1aa2bae75a3b4/w/c7260aa152d18de55edcd616/e/5ad6f41ebc88b619b5af86a6

for 1:0.333 the link is
https://cad.onshape.com/documents/7836c5f431c5b53555aaa8f0/w/7393cf4320bb1b4590106302/e/27cf1a1b713da30de71cf217

NeilCooke

I’ve not looked at your doc but type in the ratio as 1/3. With just 3 decimal places you will get rounding errors very quickly. 

chand_basha

hmm, it is also not working sir. The thing is before going to give gear relation itself the tooth is not meshing with each other properly. let me tell you in brief, in the first case I have taken teeth as Tr=80, Ts=40, Tp=20. so the ratio of teeth from the sun to ring is 1:0.5. whereas in the second case I have taken teeth as Tr=75, Ts=25, Tp=25. so here the ratio will change to 1:0.333 or (1: 1/3).