The original 17' turbine called for using 16" rotor plates, however they stated that the large magnets were pretty close to each other, so I am using 18" rotors. I am also using a 20" long piece of 5" schedule 40 pipe for the yaw bearing, primarily because my top stub for the tower will be made from 4" schedule 80 pipe and the 5" fits over it with extra a little extra room.

Other modifications included beefing up the entire spindle housing assembly, the stator brackets and the yaw bearing, in addition I had two 30" OD plates made up out of 1/4" steel that will be used to hold the blades on rather than use wood.

I started out by using a piece of 6" schedule 40 pipe for the spindle housing about 7" deep. Using two plates of 1/4" steel with 6-1/2" OD and a 2" hole cut into the center I welded the spindle shaft and housing together.

Rather than use round pipe to connect the spindle housing to the yaw bearing I decided to use some 4" x 6" x 1/4" rectangular tubing. It gives me more surface area to connect the two pieces as well as making it far easier to put the spindle housing on the 5 degree up-slant.

I also put the housing at a slightly greater angle as well, about 8 degrees rather than 5. I was concerned about blade flex and having them strike the tower stub so decided to increase this a bit.

Rather than using flat stock for the stator supports I used 1-1/2" x 1/4" thick angle iron, this will supply additional support for the stator. A couple of these supports were also welded to the yaw bearing where they had to be profiled to fit into their positions.

After about a day and a half I completed up most of the housing/yaw bearing without the tail support. Wherever possible I welded from both sides (if accessible) for even a stronger assembly. I am looking for some pipe/tubing that will fit better than what I have. But here is a bunch of pictures of the unit to date taken from various angles:

Here are more pictures of the assembly with the tail pivot:

Here are a couple of close ups of the tail pivot box section:

Next I moved my attention to fabricating the tail section. I cut a length of pipe that fit over the tail pivot and cut a section out so that it would pass over the boxed section. I approximated the rotation of the tail from 'normal' to 'completely furling', marked the tubing and cut out a section so that the tail could move it's full range of motion. I tried to get as close to optimal, and later on will probably need to 'tweak' this cut out section.

Then I used a 8-1/2' length of 1-1/2" pipe, cut it at 20 degrees and cut out a birds mouth so that it would fit over the pipe. I then had to use a jack stand on top of a small table to hold the pipe level so that I could weld it on. I then used some 2" wide 1/4" thick steel to reinforce the tail, in addition to two vertical braces and welded the entire thing up including a cap for the tail pipe. I will have to add some additional steel onto the tail so that I can mount the fin, but a pretty good start.

Finally I threw together a stand so that the entire assembly could be put together and moved easily.

Here are a bunch of pictures showing the tail on the assembly:

Unfortunately my chuck has a maximum capacity of 10" so I had to put the rotor on the knee mill, and using an adjustable boring bar opened up the inside hole to almost 5". Since I was on the mill I next put in six holes on a 6" bolt circle. Taking the plate over to the lathe I could now chuck it using the inside diameter and turned the outside diameter to about 11-3/4".

The brake rotor will be mounted behind the hub and held on by the 1/2" stainless steel threaded rod.

The brake caliper can be simply bolted on or it could be mounted so that it floats. I had a short piece of 4 x 4 x 3/16" square tubing and milled out a slot in one side so that the caliper would fit, I ended up using a die grinder to make it fit as good as possible while still allowing it to move freely. I had to cut away one portion under the caliper so that it would not hit the rotor.

Then trimmed the length and put on a back plate that will be used to mount it to the turbine housing. I could not put the brake caliper on the next vertical slot as when the tail furls it would have come too close to the brake mechanism, so I put it down into the next slot.

I modified the brake, the engagement rod was too short for my purposes so I used a longer piece of 1/2" round stock and modified it to fit the way the original shaft worked.

Finally I added a bracket on the back side to help hold the engagement rod in the proper position. Later when I know how I am going to engage the brake I will adjust the length.

Here are some pictures of the mounted brake caliper and rotor

While at it I also welded in the two collars that keep the yaw bearing square on the stub, as well as a stop collar so that when I retract the stub it will have a positive stop.

Here is a picture of the top of the stub with the collars welded on: