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Helical Compression Springs


New member
Does anyone know of a Helical Compression Spring Start Part that allows the user to enter the Wire Dia, Coil Dia, Free Length, & total coils, and no matter what length value you put in, the amount of coils would automatically update?


New member
You don't want a start part, you want a generic part driving a family table of springs. Just set up relations to get what you want to have changing with the inputs.


New member
Can you give me an example? We have tried to write relations, but the number of coils keeps coming out wrong. We currently have a start part, with relations & parameters, that is a variable pitch, helical sweep. You enter in the wire dia, length, coil dia, & # of coils and it automatically creates the spring, but the # of coils is never accurate. I am trying to find a better way of doing it.


New member
i think if we can work oout with pro/program using the same relations as keshav and immeditely we run the programit asks for the required if we create those prompts.


New member
Thanks keshav, that is what we do for a spring with a constant pitch, but I am referring to a variable pitch spring. We've tried similar relations and parameters, but with no success. Can it be done?


New member
I think you need to set up relation for start pitch and end pitch.

Here is the example.

total_number_coils = 6

length = 12

pitch = length/total_number_coils

I assumed that (D18+D19)/2 = length/total_number_coils

Pitch value at start point

D19 = 2*pitch/3

pitch value at end point

D18 = 2* (2/3) * pitch

You have to set up some relations depending on how many points do you like to consider during giveing variable pitch.

Any further please write to me.

Good luck