how to mount vertical axis turbine atop a tapered roller bearing?

[sneakyimp]

I'm making a wind-powered sculpture (powered by a VAWT -
http://en.wikipedia.org/wiki/VAWT) and I am trying to construct a
rotating turntable as the base of the VAWT. I tried a 6" lazy susan
bearing but it's loud and there's too much friction. I'm thinking I
should try and get a tapered roller bearing. Something like this:
http://www.vxb.com/page/bearings/PROD/Tapered-Roller/Kit9338

The reason I've chosen the tapered roller bearing is to support both
the axial load from the weight of the turntable and the radial load
that will no doubt arise when wind starts blowing on this thing.

The problem is I have no idea how to mount the bearing. I'm imagining
a shaft will attach to my turntable by means of a hub so that the
motion of the turntable will transfer torque to the shaft. The shaft
will then go through the tapered roller bearing which will be somehow
mounted on a supporting stricture. I'm picturing a flange mount or
pillow block to hold the bearing but I haven seen any kind of housing
for the tapered roller bearing.Totally at a loss here about how things
connect.

Another problem I have is that I have only seen tapered roller
bearings with inner diameters of about 20mm and higher. While this
sounds like a good size shaft to support my turntable, I haven't been
able to find any hubs or flange mounts to connect a shaft to my
turntable for the transfer of torque. I've managed to find some 4mm
and 6mm universal mounting hubs with set screws which look great
though:
http://www.pololu.com/catalog/product/1083

I know all of this could be done with keyed shafting by a machine shop
but I simply don't have the budget for that.

Any advice would be greatly appreciated.

[Randy Haas]

A normal ball bearing will have a axial load rating of between .25 to .
50 times the static radial load rating (Co) - check different
manufacturers sites for further details. The tapered roller bearing
would be overkill and would limit your selection options. Probably
would want to look at stamped steel bearing housings to keep costs
down (http://www.vxb.com/page/bearings/PROD/Kit8859, for example).
They do make keyless bushings to transmit power, such as the Fenner
trantorque. What is the wind turbine powering and how?

Randy

[sneakyimp]

Post by Randy Haas
A normal ball bearing will have a axial load rating of between .25 to .
50 times the static radial load rating (Co) - check different
manufacturers sites for further details. The tapered roller bearing
would be overkill and would limit your selection options. Probably
would want to look at stamped steel bearing housings to keep costs
down (http://www.vxb.com/page/bearings/PROD/Kit8859, for example).
They do make keyless bushings to transmit power, such as the Fenner
trantorque. What is the wind turbine powering and how?
Randy

Randy, thanks very much for the excellent information. I concur that a
tapered roller bearing is a bit over kill for this project. That
bearing you linked looks pretty great. I think I like this one even
better:
http://www.vxb.com/page/bearings/PROD/3-4inch/Kit7334

It looks like it's not just shielded but sealed as well which is good
because this project is going to live outside.

The wind turbine is going to be connected to a speed reducer.
Something like this:
https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=62168&GroupID=786

Unfortunately, those are the only affordable speed reducers I can find
and they have a 6mm shaft. The speed reducer will have a ratio of
about 20 to 1 and will be driving a music box wheel. There's no real
need for high amounts of torque. The music box wheel should spin
quite easily.

So I'm now wondering where to find a good flange mount or wheel hub
which I can use to couple a rotating turntable to my shaft. Ideally a
set screw or clamping hub. I've seen this really nice hubs for R/C
vehicles but they are just too tiny:
http://www.pololu.com/catalog/product/1083

I managed to locate these which look pretty good:
http://www.globalindustrial.com/g/hvac/parts/fan-blades/hubs

And there's also these:
http://www.acehardwareoutlet.com/productDetails.aspx?SKU=998012109

I find it really hard to believe a clamping hub is so hard to find.
Seems like such an ordinary thing.

[Randy Haas]

Here are a few links for hubs:

http://www.robotcombat.com/products/hubs.html

http://www.mfgsupply.com/GoMiniHubs.html/mv_session_id=M24xZPgA

http://www.northerntool.com/shop/tools/NTESearch?storeId=6970&in_dym=1&Nty=1&D=than&Ntx=mode
matchallpartial&N=0&Ntk=All&Ntt=gocart
hubs&cmnosearch=PPC&cm_ven=PPC&cm_cat=Google -
K70&cm_pla=generic&cm_ite=gocart hubs

http://www.willardssmallengines.com/shop/go-kart-parts/axle-hubs/page1.html

Randy

[sneakyimp]

Thanks for the hub links Randy. I ended up using an aluminum pulley
from grainger industrial as my hub. Got a great turntable which'll
spin for 4 minutes from a single initial spin. My problem now is my
turbine blades which always seem off-center and too heavy. Need to
lighten up.