Have a question for the group, need to make some lazy susans for table tops, and am struggling with relationship of the mechanical bearing part, 

and it is.

is there a formula to size the radial mechanical part in relation to the base and top, like a percentage ect. i can see difficulty in not doing it correctly and allowing the top part of susan to tilt when loaded, 

i've made a couple but was'nt  happy with end results, thanks for any replies.

rj in az

Never made one but would guess the diameter of the mechanism should be at least half the diameter of the top. 

I use these very quiet, machined aluminum bearings and go as large as possible without the bearing showing so readily - https://www.amazon.com/gp/product/B071FL5QR3/.  For an 18" Lazy Susan I used a 14" bearing, if that helps (I've built several of these at 18").  I also route a channel for the bearing such that it isn't its full height and that helps it to be a bit more concealed.

Edited February 28, 20242 yr by difalkner

I have to agree. Mine is about 16 and I added an apron to conceal the bearing. I probably have a 14 inch bearing on it

yeah, it seems to be a struggle for me, have several different sizes of the mechanical unit, see what seems to work best. 

happy day

rj in az

Rule I set for my students was not for lazy susans, but the footprint of any table shouldn't be any smaller than 1/2 the diameter of the table, and to be safe make the overhang 1/5 of diameter.  Consider the outline of the footprint to be the tipping edge, and whatever weight was behind it (3/4 of the table) would need to be outweighed by  the load on the overhanging 1/4 for it to tip.  So for a 20" diameter plate a 16" base would be plenty safe.  Circles even have more than 3/4 of their area behind a tip point that is 1/4" in from the edge. A quick play with my CNC CAD software tells me a a 10" base under a 20" plate would have 80+% of the plate area behind any tip point. Bump the base to 12 inches (3/5 of the plate diameter) and the plate would have 87ish% behind any tip point.  

I use the same aluminum type. I tend to size them about 2” less than the diameter of the platter. They will take quite a load. 
Paul

These are a couple I made that were 24" and I made the base 20". Sorry I don't have a picture showing the base and the mechanism I used.

 

 

 

 

8 hours ago, John Moody said:

These are a couple I made that were 24" and I made the base 20". Sorry I don't have a picture showing the base and the mechanism I used.

 

 

 

 

 

Pretty sweet John Moody

Very nice John!