I had decided in the beginning of this project to save the metalwork for close to last because I knew it would be no big deal to bang-out in a couple of days. Now that I’ve made all the other pieces, it’s time to fabricate the frame of the machine so I can assemble it.
The stator bracket is cut from a piece of 1/4″ plate. The outer diameter is 15″ and the inner circle is 4″. The spokes are 1-1/2″ wide at the top, 2″ wide at the base, and 120 degrees apart. One 1/2″ hole for mounting the stator is on each spoke 13-3/4″ from the center. In the center of the bracket is a 1-1/4″ hole for the wheel spindle.
While I could’ve had something custom machined, I chose to go with standard parts for easy parts replacement & maintenance (bearings, etc). Therefore the spindle is a standard 1000 lb trailer axle piece that I got from Northern Tool. The assembled machine won’t weigh half that and larger ones are available for the next (upsized) machine should this one work well here.
When you get it where you like it, weld it.
The 3″ sch40 pipe will support the spindle and bracket. It’s 3-5/8″ long with a 2-1/2″ hole cut closer to one end with a holesaw. Cutting the hole closer to one end will allow the whole machine to be pushed slightly forward in relation to the yaw bearing (when mounted on the tower). Clearance between the blades and tower should be a good thing.
The Spindle Rear Support is a 3″ disc that I cut with a hole saw and has a 1-1/4″ hole in the center for the spindle, the stator bracket doing double duty as a Spindle Front Support. (A magnet works nicely here to hold the disc in place.)
Again once everything is centered & where you like it, tack it, check it, then
Weld it solid.
The piece on the left will be the Yaw Bearing. It will slip over the tower top and is made from a 12″ long 2-1/2″ sch 40 pipe. The center part is a 2″ dia piece that will be 3-1/4″ long & will connect the Spindle Assembly to the Yaw Bearing.
Before welding anything together, there are a couple of angles that need to be attended to. The connector piece is centered on the yaw bearing at 6″. I’ve put a 1/2″ shim underneath the spindle assembly, and…
a 3/4″ shim under the top. When complete, this should cause the generator to be tilted back about 5 degrees & the turbine blades will also be tipped back the same amount.
Weld ‘er Up! (I sense a trend.)
This will be the pivot for the tail boom that will allow the machine to furl, protecting itself in high winds and storms.
I’m using a 45 degree level on the spindle and clamping the entire machine assembly into my vise with the yaw bearing up.
Weld the tail pivot straight up, in-line, on the back of the yaw bearing.
The yaw bearing cap is 1/4″ plate with a 3/4″ hole in the center and is actually a left-over scrap from cutting the center out of the magnet rotors. The hole in the center will accept the line out from the generator, allowing it to run down the center of the tower. Align it, tack it, and weld it solid when happy.
Stay tuned for more metalwork… Furling and the Tailboom.
