helical gear info

[mickjagger]

Hi, does anyone know some detailed specs on the helical gears that came with the kit? The pressure angle - PA, the diametral pitch, and whether they are left or right hand. We'd like to order some additional helical gears and want them to match. Thanks

[jskene]

These specs are available from www.mscdirect.com. Search for "helical" and you will be taken to their gears pages. The gears can also be viewed at BostonGear.com

[mickjagger]

Hi, yes the specs are available, however, there are several different types of the gears listed. I need to know the correct type to match the new gears we want to buy. The pressure angle is probably 14 1/2 but what is the diametral pitch. The catalogs list several 8,10,12,14, etc
As well as right or left hand. Thanks,

[jskene]

Page 52 of Boston Gears Gear Catalogue ( a 3.2M file) (http://www.bostongear.com/pdf/catalo...rs_catalog.pdf) indicates that the H1212R gear that came with the robot kit has the following specs:

H1212R
-pressure angle 14.4 deg.
-helix angle 45deg
-12 transverse diametral pitch
-pitch diam 1"
-Right hand gear (the H1212L is a Left hand gear)

If you plan to mate this gear with another one, you need to use a 12 pitch gear also, with Right hand teeth. If the pitch diameter is larger than 2" (the diameter of the mating H1224R gear that we got), then you will need to modify the plastic gearbox housing accordingly. I posted a note elsewhere on this board on how to do this.

[mickjagger]

Great, this is exactly what I was looking for, thanks!