Worm Gears Component Generator

[Anonymous]

I'm given this data to generate my worm gear set with:

Worm Gear Data:

Diametral Pitch: 8

Number of Teeth: 27

Pressure Angle: 20 Degrees

Pitch Diameter: 4.219

Base Circle Diameter: 4.523

Circular Pitch: .491

Circular Thickness: .246

Root Diameter: 3.906

Face Width: .783

Worm Data:

Number of Threads: 5

Pressure Angle: 20 Degrees

Pitch Diameter: .938

Lead Right Hand: .375

Lead Angle: 169 Degrees

Addendum: .156

Whole Depth: .313

Chordal Thickness: .204

Inner Diameter: .619

Outer Diameter: 1.244

Center Distance: 5

My problem is it keeps changing data and/or failing.  It particularly hates the 27 teeth (always changes it), never shows a 5.4 gear ratio (probably because it hates the 27 teeth), and won't accept an addendum of less than 1.  Is this feature limited to only certain set gear setups?  Anyone have a good tutorial on generating this stuff manually since the automated tool won't accept these values (which I have to work with)?

[Anonymous]

To clarify, the ratio I m refering to is the speed ratio:

mG=Ng/Nw

Ng being the number of teeth on the gear

Nw being the number of threads on the worm 

I "assumed" this to be the gear ratio because the numbers it was trying to spit out was consistent to this formula.... whenever it changed the number of teeth, the gear ratio changed as well and the number seemed to match the above formula. 

[Anonymous]

Based on the lack of responses, I take it few use it or it doesn't work as intended. 

Why isn't there a reset button?  As soon as it fails to calculate, it is forever stuck in that mode.  Hard to try and figure it out when it won't even accept any input as valid.  What input is valid?  Short of when I initally launched it and hit create based on the defaults, it hasn't accepted any inputs as valid ever since.

[Anonymous]

hey bro,

i think it'd be if you attached with screenshots as how you do it.

thanks in advance mate;)

Melvin