I currently have 3x 24" computer monitors on 3x Sanus SR213 full-motion articulating arms that stretch outwards about 12" mounted to 3 consecutive studs. I've recently rearranged my furniture and now the ideal placements for those arms don't fall on studs and I figured I might as well upgrade how they're mounted to prevent having to remount them in the future... That said, I'd like to build a 4' linear motion rail that I can mount them to. I am known more as a web developer than one who's crafty with my hands. The last time I was in a workshop was middle school doing basic stuff with band-saws and such, so please bare with me... The Sanus SR213s have 2 vertical mounting points that are 5" apart so what I was thinking is building 2x double-v rails, mounting one above the other, then having 2 upper and 2 lower wheels for each monitor on each rail (a total of 8 wheels per monitor) attached by some sort of plate or bracket that the wheels and the SR213 arm can mount too. Does something like this sound do-able? Practical? Economical? This is for a hobby, not a business, so I don't have a large budget to work with. Any suggestions to improve the idea and/or decrease the overall cost?
While I applaud your desire to use a V-slot based system, once you've priced 24 wheels, 6 plates, 2 lengths of rail plus a number of assorted screws, washers, spacers, and brackets you'll find yourself considerably ahead just to head down to the local home center and pick up a sufficient length of stain grade oak 1x8, a can of polyurethane stain and a handful of screws long enough to solidly anchor it to the studs. Attach the mounts to the board prior to attaching the board to the wall.
True, but then they're rather stationary... yea, they're on articulating arms, but that doesn't really give them much room to move when working with 3 because they don't line up properly if you don't move their mounting points. Curious though, why would you attach the mounts to the board prior to attaching the board to the wall? Wouldn't that make it more difficult to attach to the wall with nuts on the back side? Why wouldn't you just drill through the board and into the wall, since the board is secured to the studs it'd still reinforce the wall at the monitor's mounting point, wouldn't it? Also, would a piece of flat metal not work the same and provide a smaller profile than a 1" piece of wood?
Sorry, I was presuming that you would be recessing the nuts into the backside of the board. Drilling them after mounting the board just does more damage to the wall. The weight of the monitor out at the end of the arm creates substantial outward pull at the top of the mount bracket and this outward pull will be flexing outward whatever you have mounted across the wall. And the thinner it is, the more it will flex, causing the monitor to dip at the front. Sure, metal is stiffer than wood and a thinner section is possible but I probably wouldn't go with less than 1/4" thickness in steel or 5/16" in aluminum. But if you're truly wanting to do this with the proper techno/contemporary look it deserves, V-slot actually is an ideal solution. Just give up on the idea of using wheels. Sure they're adjustable but then you'll find it difficult to get the monitor to stay put once you get it adjusted. You'll also find it extremely difficult to get the holes for the wheels drilled with the proper level of precision to be able to pull this off. Instead I would suggest just using flat plate brackets attached to the track with screws and T-nuts. This will allow adjustability up front but keep things in place over the long run. (It'll also save you about $125 in wheels, shims, and spacers.) You'll need 2 1500mm lengths of 20x40 V-slot cut to around 50" (assuming the studs you're attaching to are at a typical 16 or 24 inch spacing) and 3 lengths of 1/4 inch aluminum bar about 3 inches longer than the mount bracket and slightly wider. Drill 2 holes top and bottom, offsetting the holes diagonally both locations so you get a wide grip side to side and grab both channels of the rail. Attach the plates to the rails with M5x10mm screws into T-nuts. You may need to reverse the T-nuts to get a full grip on the threads. Attach the rails to the studs with a couple of 4 inch deck screws recessed in the channels and set solidly into the studs.
I would certainly prefer wheels, and had planned to drill and extra hole on the bracket for some sort of thumb or butterfly screw that would tighten against the track to hold it in place. However, you do have a valid point in terms of drilling the holes just right for the wheels and the cost of such wheels. A friend of mine does a lot of woodworking and said he had the tools to drill holes in metal, but I'm not sure what tools he has or how competent he is when it comes to precision. As for your proposed plan, aside from not having wheels, the other matter I'm not too found of is the thickness of it. The Sanus SR213 fully collapsed offsets the monitors about 3.5-4" from the wall, so adding another 20mm from the extrusion and another 1/4" for the plate tacks on another inch (Which is also why I'm not too keen to the idea of using a wooden cross-board). Any suggestion for making something with a smaller profile? I had also thought about using a T-Track and putting wheels in it, though most T-Tracks that I've seen are for tables and probably aren't designed to hold that kind of weight... Thanks for the time and amount of thought you've already put into this thread... I don't mean to sound ungrateful by negating any of your ideas, I just have a limited amount of space and, unfortunately, money. I suppose I could toss the Sanus arms in favor of slimmer ones, but that too costs a pretty penny to find decent full-motion ones.
My apologies for the misguided initial thoughts as I wasn't quite following where you were wanting to go with this. Based on some simple assumptions (10 lb monitor, 2:1 lever arm on the support, and 24" stud spacing), how viable a concept based on openrail applied to flat metal bar would be is entirely based on acceptable flexural tolerances. Quick numbers using 3/8" x 2" bar give an outward flex of just under 1/16" which would mean a vertical dip of approximately 1/8" for a fully extended monitor. Again, this was a quick number based on rough assumptions and simple calculations. If you don't plan to have the monitors extended this becomes irrelevant and using numbers based on actual conditions will also likely reduce the deflections noted. Using a 1/4" by 2" steel bar would give a similar but slightly larger deflection than the 3/8" thick aluminum bar but be far more difficult to drill the required number of screw holes. As far as getting the upper and lower rows of holes in the plates in proper alignment, I suggest using a simple drilling template.
