Nice build Ken! How is your gear mess with that 15T NSR pinion and the 26 Crown? Silent or whiny ?
Hi Jim, as long as the gear pitch is close to .5 module, on both pinion and Crown (or Spur) , tooth count is irrelevant. It is when manufacturers try to jam too many teeth into a fixed dia. that mesh issues arise. In order to have a fixed diameter gear with differing tooth counts the manufacturers must alter the tooth profile, and , therefore pitch. At a certain point, this will affect the “acceptable” pitch, resutling in poor mesh.To keep an acceptable (close to .5 module pitch) , higher tooth count gears need to be of a larger diameter, which Kens’ is, so mesh should be just fine.
In an inline configuration, you can use any diameter pinion diameter you choose, but, only a 5.5mm pinion will allow the use of the motor shaft as a centering mechanism.
Here is a little conversion “thingie” that will allow you to calculate the “perfect” tooth count for any .5 module pinion/spur. (Crowns all use different diameters for their individual tooth counts, and as such are all “perfect”
Take the diameter of the gear (pinion or spur) and multiply x 2……..then subtract 2…….the resulting number will be the perfect tooth count for a .5 module gear.
eg……..
A 5.5mm pinion x2 = 11 – 2 = 9………..the perfect .5 module tooth count for a 5.5mm pinion is 9.
On pinions you can generally go up or down 1 tooth from “perfect” so an 8 or 10 tooth 5.5mm pinion will work just fine……any more either way, and you will have issues.
The same calculation works for all .5 module pinions, and Spur gears……..on Spur gears, 2 to 3 teeth either way from “perfect” is generally acceptable.
Cheers
Chris Walker
