How do I build a windmill in Dwarf Fortress?

I understand you need to put an axle under the middle square, but does it have to be a vertical one? I would have thought you'd want it to be:

ground level:

XXX
XOX
XXX

one level down:

RRR
AAR
RRR

Where R is Rock, and A is your Axle (one is vertical, one is horizontal) but can you build a windmill over two channeled squares?

I basically want a water pump and a windmill to power it...

Solution 1:

Yes, the axle under the middle square has to be vertical. Your adjacent vertical and horizontal axles won't work because you have to use a gear assembly to change the direction of power flow. (Alternately, you can build a gear assembly under the windmill instead of an axle.) See http://df.magmawiki.com/index.php/DF2010:Windmill.

Solution 2:

While you've got the right idea, your understanding of Dwarf Fortress machine part mechanics is a little bit flawed.

The diagram you present above would work if you replace the vertical axle with a gear assembly. (Alternatively, you could put the gear assembly 1 z-level below the vertical axle, though you'd have to move the horizontal axle down to the level of the gear assembly as well.)

Also to remember -- you need to channel out the floor tiles when you're trying to transmit power vertically; it's not always apparent whether you've remembered to remove the floor when you've got an axle icon taking up the tile instead.