The 2" tubing gives is good fit and since it is polished to a high
finish, it swivels nice and smooth. I was originally going to use
sched 40 pipe but the guy at the stainless place (KATO Marine
in Annapolis) talked me out of it. Said sched 40 pipe was very
heavy and cost 3x what the tubing did. Also, the tubing is polished
to a high luster so it looks really nice. As I suggested earlier, it
might be good just to have a 6" piece of tube welded onto the
top of the pole. The instructions said that the PVC collar would
have to be slightly enlarged to accomodate the tube, but that
turned out not to be the case. 2 collars were provided, one fit
the tube perfectly.

Doug

"Geoffrey W. Schultz" wrote in message
.17...
It's definately a blade balance issue, but I've carefully run through
the balancing instructions and I can't find any blade that's heavier
than the others. I'm sure that there are some harmonics that are
causing it, but I haven't been able to figure out how to balance it.

None of the PVC fittings that came with it provided what I would call a
snug fit. There was a good 1/16" clearance around the pipe, which
certainly is enough to allow vibration.

-- Geoff


"Doug Dotson" wrote in
:

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube
fits the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall
strength
of
these would be greatly appreciated.

-- Geoff