Hi Brian, Pilou Karsten and Michael G,
Thanks for all your help
I had a play with Barry’s VaribleHelix.nod and could not get it to run.

I read Brian’s pdf on his Variable Pitch Helix script. And had a play with the scripts in MoI.
They work beautifully.
I am trying to get my head around the Maths to possibly adjust Karsten’s Helix2Helix.nod.(if ok with Karsten)
Adjustment 1: The major helix to have a variable radius.( Looking at Helix2Helix, I cannot work out where the Second radius needs to be inserted)
Adjustment 2: The minor helix to have variable pitch and radius. (Replace the standard Helix-node with a Variable-Pitch-Helix-node-bundle from within Karsten’s macro )
Adjustment 3: Major and Minor Helix to be independently Left and Right handed. (swapping Sine and Cosine. But I am lost, truly :(

Comparing the Script Maths and the Node Maths I did notice the similarity:

x(t) = (R1 + R2*t) * sin(360*Num_turns*t)
y(t) = (R1 + R2*t) * cos(360*Num_turns*t)
z(t) = N * (p1 * t + p2 * t * t)

from Brian’s script and:

c*cos(PI/a*b)
c*sin(PI/a*b)
from Karsten’s node which, I think, uses a Progression node as the z(t) equivalent

So that’s where I’m at...
Any help would be greatly appreciated.