Rotating Monitor (LCD) - Pizza Pan vs. Lazy Susan Bearing

[csa3d]

This weekend I thought I'd give a go at another Rotating Monitor solution, based off some previously done ideas.  The LCD is mounted to a 16" Pizza pan and is bolted to a 12" Lazy Susan bearing for the axle.

Pros:
    - Lightweight, your monitor is heavy enough for a hobby motor!
    - Perfect circle all ready cut, no need for any jigs, routers, etc.
    - Machined ventilation holes mark the center radius for you with a few lines.
    - Thin setup!  This setup could probably work very well in a tight place.
    - Metal pizza plate does not require any additional adapter plate to mount the VESA drilled monitor.  Just drill out the approriate holes right on the plate.

Cons:
    - 7$ Lazy susan bearing has slight side/side play during rotation
    - Requires a dremmel tool with cutting disk to "manipulate" the joining of the two metal surfaces
    - Lazy susan bearing is poorly constructed, and seems to struggle when a hobby motor is finally attached to it.

Conclusion:
    While in theory, one would think this setup would work well, the poor construction of the lazy susan bearing used in this example has proven this example as a failure for my particular application.  This writeup is for those considering going down this route themselves.

Parts:

    1x    16" Pizza Pan (Target.com)
     

    1x    12" Lazy Susan Bearing (Lowes.com)
     

    4x    Small bolts w/ lock nuts and washers

Tools:
    - Drill & drillbits matched to bolt sizes of VESA screws and bolts mentioned above
    - Dremmel Tool w/ cutting disk (2 or more.. you never know)
    - Adustable wrench
    - Screw driver (for bolts above if necessary)

Instructions:

1.  Take your Pizza pan, flip it on it's back side.  Draw an "X" from each foot on the bottom of the pan.  Thanks to the precise machining of the air vents, the middle is practically laid out for you.
     

2. Take the bearing, and flip it upside down so the largest flat metal part is facing upwards.  Using a ruler, line up and draw an "X" down the middle of the bearing using the mounting holes provided.
     

3. Now place the bearing on top of pizza pan, aligning both "X's".  By doing so, you are assuring that the bearing will spin around dead center of the circular plate.
     
     

4. Making sure to not bump your newly aligned bearing, mark an "X" through the four mounting holes on the top of the bearing.  You will need to rotate the bearing so that nickel sized hole reveals the mounting hole beneath.
     
     

5. Remove the bearing, and drill out 4 holes where you just marked, big enough for your bolts to fit through.  Then bolt down everything.  You now have the pizza pan mounted to the bearing, in dead center.
     

* Note:  You may have to use a dremmel tool to cut away the indented metal parts, which catch on the bolts
* Note:  You may have to grind down your bolts w/ a dremmel to be short enough to pass under the rotating bearing
     
     

6. Now you need to figure out how to mount the Monitor to the plate using the VESA mount holes on the back of your monitor
     

    - To do so, grab a piece of printer paper, and a pencil
    - Place the paper over the VESA mount holes, tape it down or hold it good and tight.  It must not move at all!
    - lightly rub the pencil across the holes, which will reveal them onto the paper (Good old 1st grade crayon rubbing trick!)
    - Remove your new mount hole template

     

7. Now, we'll use complex math to create an "X" down the center of this hole template, so we may align it to the "X" on the pizza plate the same way we did with our bearing.

    * My hole template had two holes to the far right and left of the 4 VESA holes, so this is what I did... *
    - Draw a diagonal line from the right outer most hole center, to the top right VESA hole
    - Draw a diagonal line from the right outer most hole center, to the bottom right VESA hole
    - Draw a diagonal line from the left outer most hole center, to the top left VESA hole
    - Draw a diagonal line from the left outer most hole center, to the bottom left VESA hole

      You now have a diamond..

    - where your diamond crosses at the top and bottom, line your ruler up and draw a vertical bisecting line
    - where your diamond crosses at the left and right, line your ruler up and draw a horizontal bisecting line

      You now have an "X" through your VESA mount holes

    - I connected my 4 VESA holes, but ended up not needing to for any reason.  Feel free to do so, or not.
    - Remove your new mounting template which looks roughly like so..

     

8.  Because the hole inside the lazy susan bearing is smallish, you will need to trim down your template

    - Cut the template into a square, just a tad bit larger then the 4 VESA mounting holes.  If you screw up, start rubbing again!
    - Cut a circle out of the center of your trimmed template.  You will use this to align the center with the "X" on the pizza pan
    - Remove your newly trimmed template

     

9. Place the trimmed template inside the lazy susan bearing hole on the bottom of the pizza pan, aligning the edges of the "X" of the template, with the edges of the "X" on the bottom of the pan.

     

You should now be able to confidently mark the 4 VESA holes onto the pan using your marker once again.
     

10. Using your drill with a bit appropriately sized for the diameter of your VESA mount screws, drill out the 4 mounting holes you just marked.  Clean up any sharp edges with your dremmel tool.

     

11.  Flip your monitor upside down, and align the newly created mounting holes.  Insert your VESA screws and screw them into the monitor.  You have successfully mounted an LCD onto a pizza plate which will spin on your lazy susan bearing.

     
     


** Note:  Before you mount the LCD, you will have to drill 4 more holes to mount the Lazy Susan Bearing's base to your wood surface.  I forgot pics of this step, but it's pretty easy..
    - Flip the pan upside down, so the bearing is facing up
    - Take a drill, and hold it so the drill bit is going through one of the 4 smallest holes on the large metal plate.  (the holes closest to the circular center on the 3" rim)

      * I also suggest first aligning those small holes to the "X" in case the bearing shifts during drilling, cuz it will unless you have some awesome clamps I didn't have

    - Repeat drilling out all 4 holes
    - Enlarge these new holes with a slightly BIGGER drill bit ONLY on the PiZZA PAN.  That way your screw head can fit through the pan, but not the bearing mount holes.
    - Clean up any sharp edges left on the front of the pan with your dremmel
    - To mount to a wood surface, with the monitor OFF, you'd screw from the top of the pizza pan, through the enlarged holes, into the mottom mount hole layer of the lazy susan bearing.


So in conclusion, if one wanted to mount an LCD this way, this is how I did it.  I do not feel as though my lazy susan bearing is of the quality it needs to be to make my fabrication considered a successful one.  The cheap 7$ bearing has a lot of wiggle side to side during rotation, is on the noisy side, and feels as though the bearings get jammed ofen, even after lubrication.

Good luck.  Hope this helps someone in some fashion or another.
-csa

[csa3d]

And a video of manual rotation, for proof of concept..

[youtube]http://www.youtube.com/watch?v=BA-6jzDvd2g[/youtube]

-csa

[DaOld Man]

looks good!

Nice writeup too!
 

[(+_+)]

I used the same pencil and paper trick to mark my holes

Also, like me you have all the luck in the world. Even though you have all those prefab holes, the mounting holes on you LCD don't line up. 

Nice job!

[Ritalin]

Fantastic!

Love the idea and excellent explanation.
Just wondering will you be including a "stopper" or break so it locks into place, etc?

Again, great idea and nice work!

[csa3d]

Just wondering will you be including a "stopper" or break so it locks into place, etc?

If I decide to continue down this path, I had planned to mount switches directly to the pizza pan, which would be triggered by L-Brackets which stuck upwards from the wooden mount which the whole unit would be attached to.

Thanks for the other kind words from all.  I'm kinda at a "back to the drawing board" status with this until I find small casters..

[weisshaupt]

Nice work..

I was worried the Cheap Lazy susan bearing would have too much play in them. I think if you employed a higher quality bearing this approach will work very nicely.

My Machine uses this exact same pizza plate.. If you are getting a lot of slippage (pizza plates are unfortunatley non-stick) , coating the plate with plasti-dip spray paint did wonders for the traction on mine..

[(+_+)]

You can probably get away with sandwiching a large plastic washer (those hard white ones) in between 2 - 5/8" pieces of mdf. One board would act as the stationary piece while the other one mounts to the LCD and swivels up against the washer. The entire sandwich is held together with a bolt and lock nut and tightened just right. You can even laminate or put a thin steel plate on the side that would be rubbing against the washer to prevent wear and tear.

Thinking about this a bit more, maybe even one of those heavy duty glisdomes instead of the washer since those things are as slippery as Mario Bros slip ice.

http://www.tnt-audio.com/accessories/glisdome_e.html

[psychotech]

Great 

Nice try & great documentation 

Back to basics? A good big roller bearing should work nicely .. Just saw off everything you don't need. I did.

Check these out:

http://www.hjulex.se/index.php?id=16&type_ref_id=11&L=0
http://www.hjulex.se/index.php?id=16&type_ref_id=22&L=0

Something similar? ..oh well..

http://forum.arcadecontrols.com/index.php?topic=76867.msg810487#msg810487

And, document all !! 

Have fun 

[Zobeid]

I'm glad you posted this write-up.  I'm in the planning stages of a rotating-monitor project and I was also planning to use a lazy susan bearing.  Your comments about the low quality of the bearing worry me a bit.  I can't help thinking it would be fine if the monitor were laying flat the way a lazy susan is designed to work, but mine will be tilted up about 50 degrees from the horizontal.

I'm planning to use a panel-mount LCD with a circular wooden frame (which will also support a rotating bezel), connected to a circular wooden backing, and then connected by the lazy susan to a supporting board.  So it's quite a bit more elaborate.

I could incorporate another kind of bearing, a higher quality bearing, if I could find something appropriate.

The other thing is, it could be possible to put a board with pads of felt or teflon or somesuch underneath the pan (or the wooden backing, in mine) to support and stabilize it, do you think?

[javeryh]

I am going to give it a shot this weekend if time allows.  I have a 3" diameter lazy susan bearing - I'm hoping the smaller size decreases the amount of side-to-side movement when spinning.  I'll be sure to document my findings... 

[csa3d]

I can't help thinking it would be fine if the monitor were laying flat the way a lazy susan is designed to work, but mine will be tilted up about 50 degrees from the horizontal.

I can tell you that my example failed lying perfectly horizontal on the counter edge, being rotated by the secret motor driver and the amped up hobby motor.     I still blame the bearing.  Grip was great, and the unit is light.

I could incorporate another kind of bearing, a higher quality bearing, if I could find something appropriate.

So what I plan to cook up next is to visit a skateboarding shop, and purchase 2 individual 22mm swiss manufactured skate bearing, such as the "Bones" brand, or whatever is popular.


Then I'll drill two 7/8" holes using a fostner bit into the wooden mounting base, going only as deep as the bearing, so when inserted, it sits flush with the top of the MDF.  Repeat this for the back side.  Now, Drill a hole the size of the inside bearing diameter through the wood, and the middle of the 7/8" fostner holes.  You will essentially have simulated the inside of a skate wheel at this point, only using wood.

I'll purchase a bolt the size of the inside diameter to use as an axel, and mount it to my pizza pan.  Now slip the pizza pan axel through the bearing "axle housing" along with some washers, and tighten with a lock nut.

From my childhood experience skateboarding, the swiss made bearings spin forever, and have very little friction.  This technique should clobber any hacked wheel from the home improvement store, as these bearings were made to be abused and to spin fast.  A fostner bit runs around 13$, and I'd guess a bearing would run from 2-4$ a piece.  Bolt and nuts should be less then 5$.  So for under twenty bucks, I'm gonna give this a go next.

What do you guys think?

The other thing is, it could be possible to put a board with pads of felt or teflon or somesuch underneath the pan (or the wooden backing, in mine) to support and stabilize it, do you think?

I'm not so hyped on the idea of anything having to rub the bottom plate just yet.  Maybe my tune will change when I've create a perfectly frictionless axel, as outlined above.  I don't think, however, that gliders and bolts would be slippery enough to get the job done right.  If that method does work, it would certainly be loud.  I plan to put the cab in the shared purpose game room.. so if i'm rotating the monitor a bunch it will surely piss of the wife while she's watching tv.

-csa

[csa3d]

I am going to give it a shot this weekend if time allows.  I have a 3" diameter lazy susan bearing - I'm hoping the smaller size decreases the amount of side-to-side movement when spinning.  I'll be sure to document my findings... 

If nothing else.. we're gonna get down to the bottom of this rotating nonsense!  Can't wait to see how this works out for ya.

-csa

[DaOld Man]

If nothing else.. we're gonna get down to the bottom of this rotating nonsense! 
-csa

It aint nonsense..... It's science!!

[javeryh]

I am going to give it a shot this weekend if time allows.  I have a 3" diameter lazy susan bearing - I'm hoping the smaller size decreases the amount of side-to-side movement when spinning.  I'll be sure to document my findings... 

If nothing else.. we're gonna get down to the bottom of this rotating nonsense!  Can't wait to see how this works out for ya.

-csa

I have a feeling your "skateboard wheel" method is going to end up being the standard.  GREAT idea!!!   

I'll let you know how it goes for me!

[psychotech]

That skate bearing idea sounds real good and should work great 

Remember to take lots of pictures of the project 

[Zobeid]

I'm not so hyped on the idea of anything having to rub the bottom plate just yet.  Maybe my tune will change when I've create a perfectly frictionless axel, as outlined above.  I don't think, however, that gliders and bolts would be slippery enough to get the job done right.

It appears you and I are approaching this problem with different assumptions.  I have no interest in automating or motorizing my monitor.  I'll simply reach down and move it by hand.  I think it should be less trouble-prone, quicker and quieter that way.

I see in the video you are moving it by hand with no apparent difficulty, so maybe the lazy susan will work for me after all.

[csa3d]

I'm not so hyped on the idea of anything having to rub the bottom plate just yet.  Maybe my tune will change when I've create a perfectly frictionless axel, as outlined above.  I don't think, however, that gliders and bolts would be slippery enough to get the job done right.

It appears you and I are approaching this problem with different assumptions.  I have no interest in automating or motorizing my monitor.  I'll simply reach down and move it by hand.  I think it should be less trouble-prone, quicker and quieter that way.

I see in the video you are moving it by hand with no apparent difficulty, so maybe the lazy susan will work for me after all.

Ah yes.  It would be just find doing it by hand.  If I was going to rotate mind by hand, I would have hacked apart and used the mount which came with the monitor stand (click link to see what I'm talking about).  It rotated, had adjustable spring tensions, and "locks" at 90 degrees.  This mount, however, wouldn't work for the automated rotation method.

-csa

[spystyle]

Great write up