# sprocket design

#### rajdwip

##### New member
i wanna make a sprocket in wildfire2.0....i have an equation which drives the tooth of the sprocket profile..i cannot convert that cartesian equation to parametric equation for making datum curves with an equation ..

the equation is: y = 4[ ln ( 4/x + sqrt ( ( 4/x ) ^ 2 - 1 ) ) - sqrt ( 1 - ( x/4 ) ^ 2 ) ]

can somebody tell me the steps of makingthe sprocket aftercreating this tooth profile

outside diameter :take appropriate values

no of teeth : 54

x varies from 0.2 to 4

#### puppet

##### Moderator
thats one wierd equation whats it do ?

x = 0.2 + (t*3.8)&nbsp ;

y = 4*( (ln(4/x)) + (sqrt(((4/x)^2) - 1 ))) - (sqrt(1-(x/4)^2))

z = 0

it doesnt look like anything.

Edited by: puppet

#### rajdwip

##### New member
hi puppet

this equation will be used to make a gear tooth..thia equation defines the curve of the tooth...but can u tell me how to make a parametric equation from a cartesian equation..whats the method??i was trying for a long time..i could not do it thats y..

rajdwip

#### puppet

##### Moderator
hmm

that equation in my previous post is just a fixed up version of what
you originally posted. it does what ever you intended it to within your
range. you can make it smarter ie (parametric) by adding in some
driving geometry which will adjust along with your equation

ie your range of 0.2 to 4 could come directly from your model ie

L_limit = d34
& nbsp;

d1 is really anything ie d\$

H_limit = d66

and then having

x = L_Limit + (t*(H_Limit - L_limit))

anyways you really need a model or example to explain further.

#### Zaki

##### Member
Hi Rajdwip

I make a perametric driven gear, just check it, may it could help u that how could u make a tooth for sproket

2005-04-11_024622_gear20.zip

If u cant make it just plz tell me and I will make it for u

Zaki

#### rajdwip

##### New member
hey zaki

did u make that teeth with the above equation..pro e is simply not making a curve with my equation..can u tell me the steps which u have used to make that gear right from scratch....

rajdwip

#### rajdwip

##### New member
hey puppet..

thanx for ur help man...but there is a prob..what happens when the lower liit is zero..n the equation contains somethin like y=1/x ..that is where pro e does not accept the equation..

rajdwip

#### puppet

##### Moderator
hmm in this example

x = L_Limit + (t*(H_Limit - L_limit))

if L_limit = 0 then

x = 0 + (t* (H_limit - 0)

which will still give u some number

i guess for your situation y = 1/x where x = 0 then you might be introuble.

how about you give me all the detials for your part and i make it for you

pcd od id blah blah blah .. all the info you got. possible where you
got that equation from so i can possibly find any support material