how to mount VAWT on tapered roller bearing?

I'm making a wind-powered sculpture (powered by a VAWT -

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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:
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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. This is not a big or heavy thing, so the loads here are likely to be minimal.

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:

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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.

Reply to
sneakyimp
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sneakyimp wrote in news:24ba06cf-b521-470c-8290- snipped-for-privacy@z34g2000pro.googlegroups.com:

As a general principle, set screws on a shaft are not a good way to transfer torque.

Note that the OD and ID of the tapered roller bearings are round. The normal way to install them is to have the OD fit into a bored hole and have a step or collar on the shaft to transfer the load to the bearing. If you use a collar use a clamp collar not set screw collar.

Go to

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and search on the following part numbers,

6117K11 1497K131 6435k523 6436k14

Also, wander around the pages of the catalog near the pages that these numbers bring up. A paper version of the catalog (even harder to get now than in the old, all paper world) is a wonderful resource for ideas.

Alternatives for light loads include angular contact bearings. If the loads are really small, many versions of standard radial bearings will handle small thrust loads. You can also replace a tapered roller bearing with a single spherical ball at the end of the shaft into which you have drilled a countersink as well as a contersink into whatever the bearing sits on. You then use a radial bearing for the radial loads. You may be in the PV (Pressure times Velocity) range in which plastic or bronze plain thrust and radial bearings work well. Until you actually calculate the loads, it is very difficult to suggest specific solutions.

Reply to
Charly Coughran

Charly, thanks for your response.

I have since managed to get a nice turntable constructed with parts from McMaster. I bought a few cheap bearings after getting some suggestions like yours from a forum I found. Because this project is wind-driven, it needs to be *really* low-friction. I tried two different bearings, one flange-mounted ball bearing from Grainger and another ball bearing in a flanged case from McMaster and they just didn't have the low-friction performance I was after. A cheap $3 thrust bearing from McMaster has been magical. I've got it sitting on top of a thick washer which is in turn resting on the casing of the flanged radial bearing and then I have a bronze sleeve bearing at the bottom to provide additional lateral stability. It works great! I can spin the turntable with a single finger and it'll stay spinning for a good 4 minutes.

My problem now is the construction of my turbine blades. I've bent some sheet metal (which was a total pain) into 4 blades and the resulting contraption will turn (slowly) when I turn a fan on it but it's a lot more sluggish than I was hoping. I need to find a way to reduce weight and to better center the weight of these turbine blades on my turntable.

Reply to
sneakyimp

sneakyimp wrote in news:7aac08ef-7679-4c07-a05f- snipped-for-privacy@w19g2000yqb.googlegroups.com:

What is the diameter of the turbine? Horizontal shaft?

Reply to
Charly Coughran

The turntable is about 23" in diameter and is made of very thin plywood. The turbine blades are made of curved sheetmetal and are attached with L-brackets just inside the diameter of the turntable. I'm looking into ways to make it lighter for less inertia and hoping to find a more efficient shape.

Reply to
sneakyimp

sneakyimp wrote in news:283ca717-a241-4c39-81b8-7e32e8c6a7a7 @g20g2000prg.googlegroups.com:

Find a dead attic fan or room fan of the appropriate size. Room fans often have all plastic blades which are quite light.

Reply to
Charly Coughran

sneakyimp wrote in news:283ca717-a241-4c39-81b8-7e32e8c6a7a7 @g20g2000prg.googlegroups.com:

Look around on the pages brought up on a search of the McMaster-Carr website on part numbers:

2027K24 2090K659 1910K47
Reply to
Charly Coughran

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