JR

Jack R

07/04/2005 11:14 AM

I need ideas for a support bearing for a spinning table.


I need to spin a 24 inch round table at about 150 RPM several hours a day.
The motor will drive a belt going around just under the table at a circumference
that allows the slow speed.
What I can't find is a lazy susan or bearing that I can attach under the
spinning table and to the top of my work stand.
Because the motor is driving the table it is also pulling it sideways so a
standard lazy susan bearing might not work as they are designed for force
downward, not sideways.

Any thoughts.


This topic has 9 replies

zz

zxcvbob

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 2:27 PM

Charles Spitzer wrote:
> i built a 24" lap grinder that spins at around 125 rpm under load...

Ouch!

Nn

Norminn

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 6:36 PM



Jack R wrote:
> I need to spin a 24 inch round table at about 150 RPM several hours a day.
> The motor will drive a belt going around just under the table at a circumference
> that allows the slow speed.
> What I can't find is a lazy susan or bearing that I can attach under the
> spinning table and to the top of my work stand.
> Because the motor is driving the table it is also pulling it sideways so a
> standard lazy susan bearing might not work as they are designed for force
> downward, not sideways.
>
> Any thoughts.

What are you going to do with this thingamajig? Cosmetics important?
If you can find a junk potter's wheel, it might work.

Rr

"Robert11"

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 2:29 PM

Hi,

Any of the ball bearings types that one normally thinks of are called "deep
groove" bearings.

They will take a load downward (axial), as well as sideways; usually pretty
substantial in each direction.

Try a company like Bearing Specialties, etc.

Bob
----------


"Jack R" <[email protected]> wrote in message
news:[email protected]...
>
> I need to spin a 24 inch round table at about 150 RPM several hours a day.
> The motor will drive a belt going around just under the table at a
> circumference
> that allows the slow speed.
> What I can't find is a lazy susan or bearing that I can attach under the
> spinning table and to the top of my work stand.
> Because the motor is driving the table it is also pulling it sideways so a
> standard lazy susan bearing might not work as they are designed for force
> downward, not sideways.
>
> Any thoughts.

Gs

"George"

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 2:24 PM

Check out http://www.mirror-o-matic.com/ for some ideas.

George Anderson
Montreal Canada

"Jack R" <[email protected]> wrote in message
news:[email protected]...
>
> I need to spin a 24 inch round table at about 150 RPM several hours a day.
> The motor will drive a belt going around just under the table at a
circumference
> that allows the slow speed.
> What I can't find is a lazy susan or bearing that I can attach under the
> spinning table and to the top of my work stand.
> Because the motor is driving the table it is also pulling it sideways so a
> standard lazy susan bearing might not work as they are designed for force
> downward, not sideways.
>
> Any thoughts.

CS

"Charles Spitzer"

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 11:51 AM


"Jack R" <[email protected]> wrote in message
news:[email protected]...
>
> I need to spin a 24 inch round table at about 150 RPM several hours a day.
> The motor will drive a belt going around just under the table at a
> circumference
> that allows the slow speed.
> What I can't find is a lazy susan or bearing that I can attach under the
> spinning table and to the top of my work stand.
> Because the motor is driving the table it is also pulling it sideways so a
> standard lazy susan bearing might not work as they are designed for force
> downward, not sideways.
>
> Any thoughts.

i built a 24" lap grinder that spins at around 125 rpm under load. i used
the following plans:
http://mrcol.freeyellow.com/grinder/flat_lap_grinder.htm and just scaled
them up for 24". i used 2 pillow blocks and a couple of pulleys to make the
arbor, and 2 flange blocks to support the axle.

chose the pulley sizes to get the speed you want. if you want my spreadsheet
that has the part numbers and places i used, send me an email. remove the
obvious from the address.

Ma

Mark and Kim Smith

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 3:55 PM

Andy Dingley wrote:

>On Thu, 07 Apr 2005 11:14:45 -0700, Jack R <[email protected]>
>wrote:
>
>
>
>>I need to spin a 24 inch round table at about 150 RPM several hours a day.
>>
>>
>
>
>
>>Any thoughts.
>>
>>
>
>150rpm is quite fast for 24inch diameter. It's fast enough to need
>things fastening down to it.
>
>For a hub, go to a scrapyard and get a car front hub. Something with
>a Macpherson strut often allows easy unbolting and re-mounting. A
>brake disk can make a base for the table.
>
>Rubber toothed belt drives will easily drive by friction alone onto a
>turned cast iron cylinder and a toothed pinion on the small diameter
>motor shaft.
>
>

Current Dodge truck front hubless designs come to mind. Maybe the 1 ton
model, 2000, 2001 year. Bottom flange ( inboard on the truck ) will
have 4 threaded holes so you can bolt it to something. The top flange (
outboard on the truck, where the rotor and wheel attach ) will have
eight studs. Maybe 5-6" total height. Nice big ol' tapered bearings in
there, too. That'll handle a load!! And guess what? With rim / tire
assembly on the vehicle, it turns out to be almost a 24" diameter if not
more. Put a side force on it all you want, that's how they work in
their designed environment. Multi-directional load.

LJ

Larry Jaques

in reply to Jack R on 07/04/2005 11:14 AM

08/04/2005 5:59 AM

On Thu, 07 Apr 2005 11:14:45 -0700, the inscrutable Jack R
<[email protected]> spake:

>
>I need to spin a 24 inch round table at about 150 RPM several hours a day.
>The motor will drive a belt going around just under the table at a circumference
>that allows the slow speed.
>What I can't find is a lazy susan or bearing that I can attach under the
>spinning table and to the top of my work stand.
>Because the motor is driving the table it is also pulling it sideways so a
>standard lazy susan bearing might not work as they are designed for force
>downward, not sideways.

Look for a tapered roller bearing. They're built to handle both axial
and radial loads in pre-loaded pairs. An auto axle and housing could
be cut down for your purposes. That would give you a fairly large
flange which had already been ground for a flat surface.


>Any thoughts.

Sounds like you're making a potter's wheel.

--
Vidi, Vici, Veni
---
http://diversify.com Comprehensive Website Development

Gp

Goedjn

in reply to Jack R on 07/04/2005 11:14 AM

08/04/2005 12:50 PM


>> I need to spin a 24 inch round table at about 150 RPM several hours a day.
>> The motor will drive a belt going around just under the table at a
>> circumference
>> that allows the slow speed.
>> What I can't find is a lazy susan or bearing that I can attach under the
>> spinning table and to the top of my work stand.
>> Because the motor is driving the table it is also pulling it sideways so a
>> standard lazy susan bearing might not work as they are designed for force
>> downward, not sideways.

Drive the table with a rubber wheel at the edge, and put one or more
idler wheels across from the drive wheel. What's this for,
pottery?

AD

Andy Dingley

in reply to Jack R on 07/04/2005 11:14 AM

07/04/2005 8:28 PM

On Thu, 07 Apr 2005 11:14:45 -0700, Jack R <[email protected]>
wrote:

>I need to spin a 24 inch round table at about 150 RPM several hours a day.

>Any thoughts.

150rpm is quite fast for 24inch diameter. It's fast enough to need
things fastening down to it.

For a hub, go to a scrapyard and get a car front hub. Something with
a Macpherson strut often allows easy unbolting and re-mounting. A
brake disk can make a base for the table.

Rubber toothed belt drives will easily drive by friction alone onto a
turned cast iron cylinder and a toothed pinion on the small diameter
motor shaft.


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