So, today I got caught up a bit after our trip to Colorado, first I hooked up the camera to get the pictures from the booster experiments out of it.
We worked on #1 (the blue machine for a bit), there had been some pretty high winds and the machine developed a 'clink' sound about once every revolution when turning slowly. The problem turned out to be in the linkages, the bolts were not a very good choice for the linkage shafts, so we replaced them with 3/8 hardened 'drill rod', threaded for nuts on both ends. This completely removed the problem. We also spray painted a black strip on the leading edge of the 'white' blade because it seems that ice builds up fairly easily there and will not melt back off again because the ice is transparant. With a black strip behind it that should warm things up enough to keep that blade ice free and balanced.
Then we were back to work on the new machine, this time the hole for the pullrod that will control the variable pitch. It took a bit to get the shaft registered completely true in the lathe, chuck, steadyrest and drill have to be lined up just so to make it work on a distance like this. A 3/8 hole is no big deal, but one that's 24" long definitely is, and it took several hours and lots of patience to get it done, but the result is as good as it gets.
I hope to work on rotor #2 tomorrow.
The pulse train that is sent to the gates of the fets (see my previous diary entries for more info and schematics) to boost the voltage:
The output of the transformer, notice the very ugly waveshape, this is not because of the booster but because of the Trace 'sine' wave inverter powering our house & office.
the voltage before the booster came on (sorry for the bad picture):
And after: (nice improvement what ?)
The new linkage shafts. For comparision two of the old bolts are shown, notice the wear on the threads which caused the 'clink' noise (it allowed the blades to move a bit without moving the spider on the governor spar):
The shaft all clocked in, ready to go:
Start of the cutting, this is a 'center' drill, it makes a small perfectly centered starting hole, which we then followed up with succesively longer 1/4" and 3/8" drills. For the final pass we used an extended 3/8" drill (12" long + another 10" welded on to that), then we reversed the shaft and did the same thing from the other side.
One 3/8" hole, 24" long... end view of the shaft, notice the light at the end of the tunnel:
