Can you help me understand what's considered a "conservative spoke angle range," a "moderate spoke angle range," and an "extreme spoke angle range"?
Some spoke nipples fitted into conventional rims will accommodate up to 12 degrees of spoke angle before the spoke begins to bend, and I'd describe that as
conservative:
The original 26" Magic Pie spokes had a very large angle of nearly 30 degrees, which I'd describe as both
extreme and totally unacceptable as it results in badly deformed/stressed spokes instead of straight ones:
I would say a
moderate spoke angle would be between 12~20 degrees maximum, but sometimes you simply have to make do with larger angles and distorted spokes in preference to radial spokes
(0 degree spoke angle means the spokes are perpendicular to the rim and therefore not ideal for transmitting torque).
I suggest you try to find a suitable rim where the holes are all positioned relatively close to the centreline of the rim like this:
But with a Magic Pie
and a 20" rim, you will definitely need to avoid any rims that have heavily staggered holes located way off of the centreline like this:
If you can find a suitable rim
(and the correct length spokes) it should be possible to lace the rim as shown here:
I had to enter 72 spokes
(instead of the Pie's 36) to enable the
spoke calculator to produce the required spoke angles and length for this particular spoke pattern
(and I then edited out the unused spokes to avoid any confusion).
The Pie's offset "paired" holes in the hub would produce a spoke angle of 4 degrees
(90-86), which would be similar to a conventional bike wheel spoke angle and will resist a lot more torque than the sometimes used 0 degree radial lacing.
Alan