Windmill not spinning at all?

[Hooha Owl]

I've built windmills before and had them work to various extents, but i cannot for the life of me work out why this one won't spin. Its y170+ and has 5 sails and I've not even hooked up my helve hammer yet, its simply just wont go. am I in a wind dead zone or something? it reads 20-110% at all times on the rotor

[Krougal]

1.21RC5?

It's a known bug.

Hopefully fixed already for next version.

[yarbelk]

geh.  I have the same issue. I was exited to not have to grind anything any more...   well; i guess I can finish the build anyway.  At least I know I don't need to rush anything.