For a G1 fit between each spiral segment, you have to add 2 points to the ends of each spiral. So it goes like this:

1. Make array of points as Schbeurd explains (someday you will have to tell me the correct way of pronouncing this nickname)... for this example, let's say there are 8 points in the array :

2. Select points 2 & 3, then copy from position of point 1 to poistion of point 8.

3. Select points 6 & 7, then copy from position of point 8 to poistion of point 1.

4. Now draw your curve through all the points.

5. Select curve, and trim excess curve length using original points # 1 and 8.

If you make multiple copies of this curve, and align them end to end to end, they will have G1 continuity... I analyzed in Rhino, and it doesn't matter if you make 2, 3, or 4 extra points the result will still be G1. But if only using one extra point at each end will result in G0 continuity.

shorty...