Replies

1. 
   DanH | Jan 13, 2009 02:35am | #1

   Something like this can be pretty dangerous if not well thought out. I'd suggest you at least look online to find some illustrations of commercial rolling walls to get some ideas.

   God is REAL, unless explicitly declared INTEGER
2. 
   FastEddie | Jan 13, 2009 02:38am | #2

   The wall might be light, but the flat screen tv near the top will create a pretty good torque.  Since the sheating is transparent, you will need to think through all your connection details carefully, cuz every mistake will show through.

   Beofe you have something custom made, look at this from Lee valley.  the big bracket is 8x10

   View Image

   With elegant and detailed webs, these cast steel (lost-wax process) brackets look great. They are finished with a black oxide, and have linished webs that provide an attractive contrast. The arm of the large bracket tapers from 1-1/8" to about 7/8" at the tip. The arms on the two smaller brackets taper from about 1" to under 3/4" at the tip. Priced per bracket. Item A requires #6 screws; items B and C require #8. Screws not included.

   				1+		5+
   A.		7-1/4" x 5-1/8" Bracket  01K32.30 View Image View Image View Image View Image		$11.20		$9.55					View Image
   B.		8" x 6-3/8" Bracket  01K32.20 View Image View Image View Image View Image		$11.60		$9.90					View Image
   C.		10-3/8" x 8" Bracket  01K32.10 View Image View Image View Image View Image		$17.50		$14.95					View Image

    

   "Put your creed in your deed."   Emerson

   "When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it."  T. Roosevelt

   
   

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   Edited 1/12/2009 6:43 pm ET by FastEddie

3. 
   Dinosaur | Jan 13, 2009 03:36am | #3

   I'd need the actual weight, dimensions, and placement of all the components to figure the metacentric height of the whole thing and run the stability calcs for you, but an educated, horseback guess tells me your outriggers are going to have to extend 3½-4' both sides of this wall to prevent it capsizing while it's being wheeled about.

   Alternatively, you could load the bottom plate of the wall with four or five hundred pounds of lead as ballast. That would permit you to narrow your empattement down quite a bit, perhaps by as much as 50%.

   Dinosaur

   How now, Mighty Sauron, that thou art not brought
   low by this? For thine evil pales before that which
   foolish men call Justice....
   

   

1. 
   FastEddie | Jan 13, 2009 04:10am | #4

   empattement   Been reading the dictionary again, have we?

   Good point on ballasting the bottom."Put your creed in your deed."   Emerson

   "When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it."  T. Roosevelt

1. 
   Dinosaur | Jan 13, 2009 10:42pm | #16

   Been reading the dictionary again, have we?

   Nope, just thinking in Fringlish without realising it again, LOL. 'Patte' is the French word for 'foot' (on an animal or piece of furniture; it's 'pied' for a person). My guess is that 'empattement' is one of those borrowed words that fill a vacancy in English descriptive vocabulary.

   Good point on ballasting the bottom.

   I view the OP's problem as similar to a ship stability calculation. Among other things, stability describes the state of equilibrium of an object at rest--stable (G below M--tends to right itself when heeled), neutral (G coincides with M--will neither right itself nor capsize), or unstable (G above M--tends to capsize). Objects possess different static stability at different angles of heel due to the transverse change of GZ. In simple terms, if you push it over far enough, it'll fall down...but until it reaches that point, it will tend to right itself once you stop pushing on it.

   Obviously, when this rolling wall is being moved there will be more forces acting on it to try and topple it than there will be when it is sitting still and--theoretically--perfectly plumb. This is similar to the differences between the static stability tests performed on ships in the yard and the dynamic stability performance of a loaded ship in a seaway.

   In both cases, the design has to provide for a sufficiently large righting moment (on ships this is derived from the righting arm GZ times the displacement of the hull) to prevent the object/ship capsizing under the worst forseeable conditions of use.

   Dinosaur

   How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....

1. 
   RalphWicklund | Jan 14, 2009 12:21am | #17

   Then, if you are thinking along the line of a weighted keel to stabilize a tall structure, then the pivot point, which in the case of a ship is the surface of the water, must be higher than center on a 9' wall and also high enough to counteract the top heaviness of the flat screen TV.

   So, instead of welding an axle to the bottom of the wall and having the wheel spread wide enough to counteract the weight above, a pivot point should be located above center on each end and a mini A-frame with wheels on the bottom attached.

   A couple of spreader bars between each frame would keep the dolly aligned and if all points were attached with captive pins it could then be dismantled for storage.

1. 
   Dinosaur | Jan 15, 2009 03:17am | #18

   Actually, the 'pivot point' isn't necessarily at the water line; it changes depending on how the ship is loaded. That's why the Chief Mate earns more than the Third; it's his responsiblity to do the stability calcs and see that the ship is loaded so it's neither too 'stiff' or too 'tender' in a beam sea (a ship that's too stiff will snap back upright so violently that masts and upper superstructures can break off; a ship that's too tender will roll too far and come back very sluggishly...or not at all).

   In practice, the Mate uses Stability Curves derived for the particular ship by the naval architects and (nowadays) software designed for solving stability problems. Twenty to twenty-five years ago, various hardware-programmed computers were used in combination with forms and tables to solve them.

   For this wall, all the OP has to do is ballast the bottom plate sufficiently; that'll allow him to get away with a narrower empattement. If he hung the whole thing from a pivot at the top of a tallish A-frame, that wouldn't improve the stability: in fact, it could make things worse: The weight would be acting up high, and would tend to capsize the A-frame.

   I know that sounds counterintuitive, and it is. One of the hardest lessons to drum into the heads of new longshoremen learning to run cargo cranes is that the very instant a load is raised off the deck--even by a quarter of an inch--the entire mass of that load acts on the head of the crane arm 'way up there 30 or 40 feet in the air--so you multiply the load times the length of the crane arm and you get 30 or 40 times more 'weight' hauling the ship over sideways as you swing it out dockside. A piddling one-ton pallet of general cargo suddenly 'weighs' 40 tons as soon as you lift it--enough to capsize a medium-sized general cargo ship while tied up to the wharf.

   Dinosaur

   How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....

4. 
   dejure | Jan 13, 2009 05:11am | #5

   Obviously, you have different options to stabilize this beast. Dependent on what would be acceptable, you could use a "Z" shape, an "I" beam shape, a "T" shape, an or an accordion (repeating "V's" opposing each other) type shape. Any of these should offer the stability needed, but having a single outrigger would require it to be longer than you'd need if it had opposing outriggers.

   If I were constructing this, my preference would be to keep the whole thing as light as possible, except at the bottom. It seems the lighter the overall structure the less width would be needed to keep it stable. As such, I would consider using 3/8 plywood for the inner framework(hey, cardboard works for door interiors). You could slot the pieces to fit together and use glue to secure the faces, but it would reduce the overall weight of the upper section. You would still be able to beef it up around the TV area.

   Where there is no solution there can be no problem.

5. 
   RalphWicklund | Jan 13, 2009 07:01am | #6

   I believe you will need more than steel studs and skin on both sides to keep this wall from racking. Have your welder fab a matching pair of 9' x 12' frames using 1" square aluminum tubing with a gusset in each corner. Connect the two frames with short lengths of tube to get the thickness you need to encapsulate the flat screen. Use the tubing also to frame the opening for the TV and gusset those corners, too. Within the opening framed for the TV, weld a pair of vertical or horizontal tubes to one of the two frames, corresponding to the location of the threaded mounting holes on the back of the TV. Drill matching holes in the tubes. Mount the TV. Add more vertical or horizontal tubing  to provide stability for the skin. Gussets may or may not be needed in all corners. Use self tapping washer head screws to fasten the panels. This will give you a very rigid yet light contraption. At each end you weld a horizontal axle to mount your wheels and gusset those to the panel frame. I would only venture a guess that your axles should extend at least 18" from each side of the wall. LARGE casters would  be best and the ends of the axles can be raised to accomodate big wheels while keeping the bottom of the wall close to the floor.

1. 
   RedfordHenry | Jan 13, 2009 07:25am | #7

   Unless it can be disassembled and bolted up onsite, transporting a 9'x12' anything will require some thought.

1. 
   RalphWicklund | Jan 13, 2009 04:48pm | #9

   Piece O' Cake. <G>

   Laying flat on the side rails of an 8' x 16' trailer

   or: Standing up on an A-frame in same trailer

   or: drag it along behind your truck - it's got Big Wheels<G,G>

   or: have the welder figure out the transportation<G,G,G>

1. 
   Snort | Jan 13, 2009 05:14pm | #10

   I made 4 walls that were moveable, for an art gallery. 2 x 4s with diagonal metal straps for bracing. Bottom plates were wrapped with 6 mil plastic. 1/2" sheetrock glued and screwed.All the walls were either in an I or Ell form.Floors were all carpeted, and once they started moving, the walls slid pretty easily, even loaded with art.http://www.tvwsolar.com

   I went down to the lobby

   To make a small call out.

   A pretty dancing girl was there,

   And she began to shout,

   "Go on back to see the gypsy.

   He can move you from the rear,

   Drive you from your fear,

   Bring you through the mirror.

   He did it in Las Vegas,

   And he can do it here."

6. 
   JDRHI | Jan 13, 2009 07:36am | #8

   It can be done.....I built a "rolling wall" for my shop/garage/shed.

   Not much more than that to add unfortunately.

   Mine is lumber framed and sheathed in ply, and there's no television mounted precariously up top.

   What ae you plans for power to TV?

   J. D. Reynolds

   Home Improvements

    

    

    

   
   

7. 
   MannyG | Jan 13, 2009 06:03pm | #11

   Here's a little "outside the box" idea;

   Instead of building a completely flat wall (except for outriggers), and lose sleep over how likely it might be to fall over and kill someone, try suggesting this to your client;

   Build the wall with a slight "kink" in it - in other words, instead of a straight line (180 degree angle), make it a 160 degree angle, or something like that. Put the kink in the middle or closer to one end, change the angle a bit, whatever. Experiment a little. Think of ways to make the kink useful (like putting a white board on it for messages or something like that).

   The point is that, with enough of a kink, the wall will be almost impossible to tip over. My guess is that the offset of the kink necessary for this will be less that the size outriggers you would need to make a straight wall similarly stable. It also eliminates the chance of anyone tripping over the outriggers or simply being annoyed at having to constantly walk around or step over them.

   In fact, take the idea one step further and make the wall a slight arc!

   It is a cleaner and more "contemporary" solution, but not to everyone's taste, I'm sure.

   Edited 1/13/2009 10:05 am ET by MannyG

   
   

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   Edited 1/13/2009 10:05 am ET by MannyG

8. 
   smslaw | Jan 13, 2009 06:18pm | #12

   Could you hang it from some sort of rail on the ceiling or at least attach it to the ceiling, so it can't fall, even if it is also on casters? Does it need to be able to move anywhere in the warehouse, or could you limit the travel to a straight line?

9. 
   mike4244 | Jan 13, 2009 08:21pm | #13

   Have the flat screen tv installed between studs with a provision to raise and lower it. Sliding door hardware on each stud vertically makes this work smoothly.The tv might be light enough so a hoist is not needed,or something as simple as a boat winch with removable crank.

   Out riggers on the bottom for stability can be on a pivot.When moving the wall turn them at 90° to the bottom and pin in place.When at new location if you need to reduce the footprint,turn at appropiate angle and pin in place.

   This sounds very straightforward to me,although I admit I have never done or seen a movable wall.The sliding door hardware will work, I built a panel saw with this stuff.

   mike

10. 
    xxPaulCPxx | Jan 13, 2009 08:46pm | #14

    Here is my idea:

    The center section where the TV is held is the main weighted area.  To either side are two hinged wings, they slope down to half height 4'6", then have another wing hinged to that goes down to 0".  The center has a drawbridge that folds down to hold the wings in their angled position.

    On the wall where it will fold flat, you need to make a docking station.  Here you can roll it up, fold down a protective sheet of plywood (or framed polygal) over the center section.  Then fold up the center support and lock it to that cover.  Then fold the wings flat.

    Tu stultus es
    Rebuilding my home in Cypress, CA
    Also a CRX fanatic!

    Look, just send me to my drawer.  This whole talking-to-you thing is like double punishment.

1. 
   xxPaulCPxx | Jan 13, 2009 08:48pm | #15

   Forgot my drawing:

   View Image

   Tu stultus esRebuilding my home in Cypress, CAAlso a CRX fanatic!

   Look, just send me to my drawer.  This whole talking-to-you thing is like double punishment.