How can I calculate the length of wire needed to make a helix?

Status
Not open for further replies.
D

drkirkby

Full Member level 6
Joined
Nov 6, 2011
Messages
383
Helped
59
Reputation
118
Reaction score
56
Trophy points
1,308
Activity points
5,194
I'm trying to make a helical antenna. I know the number of turns (N=7), diameter (D=39 mm) and the spacing between each turn (S=27 mm), but how can I calculate the total length of material needed for the helix given N, D and S? Clearly if the spacing was infintesimally small, it would simply be Pi*D*N, since Pi*D is the circumference of a circle.
 

Developing the cylindrical surface becomes a triangle whose cathetus are pi*D*N and p*N (p : pitch , 27mm )

Then L = N √(Π²D²+p²)
 


May I ask what length of wire your calculations resulted in to make sure I am equating the answers correctly.

Thanks
 

nashm999 said:
May I ask what length of wire your calculations resulted in to make sure I am equating the answers correctly.

Thanks
Click to expand...

Use pythagoras theorem C=PI*D, S = spacing L = sqrt(C^2 + S^2)
L = length of one full rotation
L*N = total length
Height of helix = S*N
 

Status
Not open for further replies.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…