Helical Ugrinsky vertical turbine for your garden.

This vertical wind turbine is even more garden related as it uses ¾" wheelbarrow bearings to keep it spinning nicely. 

To keep the helical shape printing nicely without supports each segment covers 30 degrees. You need to print three segments to get a 90 degree twist, which will make it so that the spinner is self starting.   

I printed in PETG which has held up to the sun reasonably well, the spinner in the picture has been spinning for the last three summers. And then bonded the segments together using methylene chloride (Dichloromethane) which is toxic so use well ventilated or with a respirator. You can probably glue them with superglue or whatever your favourite bonding agent is.  

You will also want to print a top piece to stiffen the top of turbine.  I used one bearing at the bottom and one at the top.  I believe I mounted it on ½" electrical conduit with an outer diameter of 11/16" ( 20mm ).