ROTATING TURN TABLE

[gida2]

Help.

I'm designing a rotating workbench with vises.
6 vises (60 deg apart) on a 7' diameter steel table
(1/2" to 5/8") thick depending on the final design iteration.

I’m looking for ideas on mounting the table (Spherical thrust bearing, yoke rollers, design sites or company manufactured tables etc…)? I had some ideas but would like to here from the experts.
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Design Requirements:

Load (w/table) = 2000lbf mostly thrust with minimum radial loads ~ 100 lbf.

Revs = hardly any (hand rotated)

Environment = it’s in a weld shop
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Rotating Work Table (example)

http://www.advancelifts.com/lifts/showdetl.cfm?&DID=6&Product_ID=1241&CATID=3

Any help is appreciated,

 

[BillPSU]

We built aerial devices and digger derricks and had rotation bearings available from stock to use in this type of tooling application. Bolt to the mounting plate and to the table. Kaydon was our manufacturer and should have something in stock that would work for you. You could make your on bushing bearings but inevitably they don't work as well and are a pain to make.

 

[Pressed]

Most weld tables are open framed so you can get clamps in, going by the example, it had a flat surface. If it's flat sheeted, you could try an air surface (like air hockey) then top that with another sheet and a center pin. A machine manufacture/rebuilder uses that air float system on thier shop floor to move very large machines around.

They make large lazy susan bearings, McMaster Carr has a few. Some manufactured bearings of that size are costly, there are cheaper ones but, you will have to track them down. You could look up Kaydon, they may have something that would work for you.

If you do make your own bearing ala gida, just think about it a while, what could go wrong. Because many people have tried to built these type of things and failed.

_______________________________________
Feeling frisky.........

http://www.tailofthedragon.com

 

[Barry1961]

Slew ring bearings are cost effective and rugged.

http://www.gearproducts.com/SlewingRingBearings.htm

When I have done rotating welding fixtures in the past I used large carbon brushes. If I remember with a 70/30 brush you could get about 100 amps per square inch. There are some large brush holders made for large generators you can buy fairly cheap also.

Barry1961

 

[unclesyd]

From my recollection:
We made rotating tables of similar size for in-house use using mostly purchased components.
We had machine bases, specifically mold tables, made to our dimensions. We used a heavy top with a center hole to flange mount the bearing carrier on either on top of or under the top plate. We used a dial plate if possible or had a plate ground. We had to have a smidgen of precision.
The assembly was essentially all bolted construction. I wasn't involved with the bearings, but do recall that a tapered roller bearing carried the load, with a radial bearing to center the shaft. The work table was flange mounted to the to the shaft.
The electrical connection was through a standard rotary ground clamp on the shaft.

http://www.interlakesbases.com/products.html

http://www.americangrinding.com/

 

[diamondjim]

As noted, just search for slewing bearings
and you should get quite a few manufacturer's
who provide suitable bearings. I assume you
do not need a precision bearing. Kaydon,
Gear Products, Rotek, PSL are just a few who
can supply a bolt on type bearing. You can
also get some free engineering by consulting
them. You will also be applying moment loads
on the bearing at whatever radius the vices are
from the center of the table. Your load are
light but you will have to add the upper table
weight to the applied axial load.

 

[gida2]

Thanks - I'm going with the Kaydon MTO-265 slew ring bearing, which is also the one offered in McMaster-Carr. On the outer diameter of the table I'll use casters. These slew ring bearings are nice and the mounting design seems easy enough.

Thanks for the advice.

 

[rmw]

Here is a lint to something that might suffice.

http://www.jostinternational.com/Pages/Turntable.html

Jost (as it was told to me) had its humble start making turntables for german tiger tanks during WWII, and now make turntables for heavy duty transportaion equipment, among other things.

This type of equipment gets a hell of a beating in nasty environments, and just keeps turning. Maybe it would survive in a welding shop.

Not, however, in a MacMaster Carr price range, I would suspect.

rmw