Custom monitor stand (take 2)

[doveman]

I never got anywhere with my custom monitor stand last year but I'm ready to give it another go.

 

I've tried to knock up something in Rhino to show what I'm thinking of. All I need is something that will let me raise the main monitor and hold the lower monitor in place. When I lower the main monitor for normal use, the other monitor will just be unhooked and lay flat on the desk. The main monitor will be a BenQ 27" VA and the other monitor a Dell P2214H IPS.

 

This shows the stand raised, with the lower monitor attached. The desk is shown in dark brown, with the base of the custom stand in light brown. Attached to that is the inner pole (green) and lowered over that is the outer pole, to which the main monitor is attached.

 

 

This shows what it would look like when lowered, with the secondary monitor detached and lying flat on the base (I forgot to disable Gumball mode, hence why it looks like that):

 

This shows a close-up of the top of the outer-pole. The main monitor will be attached to a VESA mount, which in turn is screwed to a spacer piece of wood, which is then screwed to a larger piece of wood (actually I could just use a single piece, suitably shaped) which goes inside the top of the outer-pole and is secured to that with a bolt through. Also attached to the bolt is the hardware to support the lower monitor. I haven't shown the hole and removable bar that will need to go through both poles to secure the stand in the raised position, so just assume that's there.

 

The lower monitor support is shown in these pictures. I was thinking of using long strips of strong metal to form a triangle and then bent pieces of metal (think clothes hooks) with some sort of stop on would come out from the strips. The secondary monitor will be mounted to a thin piece of wood which will have holes in the top corners where it can be hooked onto the hooks. To avoid wasting space, I want the top bezel of the lower monitor to sit over the bottom bezel of the upper monitor, so I might need to hook the lower monitor on at a lower point on the attached wood and that panel of wood won't have to be as big as the monitor. I admit this is the weakest part of the design and I'm not sure if it's going to work. I originally planned to mount a block of wood at the right height to the outer-pole, which would have been easier but then I realised I can't screw anything into the outer-pole as the screws will go inside and clash with the inner pole.

 

 

This last picture shows the L brackets I plan to fix to the back of the base to deal with the gap between the back of the desk and the wall, (1) angled upwards so that the stand can't tip backwards, (2) angled downwards so that it can't tip forwards (although this is probably unnecessary) and (3) to prevent the base being pulled forward, which would move (1) away from the back wall and allow the stand to tip backwards. I intend to fit foam strips to these brackets so that they're not rubbing against the wallpaper or desk and I'll have to lower the base straight down into the gap and the positioning of the brackets won't have to be so critical if I can compress the foam against the wall as I lower it down.

 

 

Whilst I'd welcome any suggestions/ideas (although I can't attach anything to the wall or desk), what I'm particularly looking for advice about is:

 

a - what type and format of material to use for the inner and outer poles? I'm thinking there might be some square metal hardware with a lip at the end that I could use to screw it down to the wooden base but there's probably a collar I could get to attach to round hardware (like PVC piping) to do the same. I'm not sure if PVC piping would be strong enough though or if the bar I'll have to insert through both the outer and inner poles to hold the monitor in the raised position might cause the PVC to wear away over time and widen the hole, making it less stable. There's also the question of whether I can get inner and outer poles of the necessary diameter to go inside/outside each other in either a square or round material.

 

b - what hardware could I use to make the support for the lower monitor? As I said, my idea might not be great so I'd welcome other suggestions that might be easier/better. I can't bend and shape metal to make custom hardware (at least I never have and probably don't have the tools) and will need to use off-the-shelf stuff that I can just cut down to size and drill holes in.

[Mr_Burns]

Hey, I play with 2 monitors and leave them as they they are without altering when not playing. I built a shelf 21cm up from my desk and the top monitor sits on that, I then took the stand off the lower monitor and screwed a piece of wood to it and mounted it on the shelf on a hinge. The hinge allows you to store stuff behind your monitor and also gives access to the power and HMDI leads.

 

The lower monitor sits flush with the desktop and finished just under the top screen on the stand.

 

Its perfect as additional desktop but you can turn it off if its distracting.

 

The problem you might encounter with your design is if your top monitor is not at eye level, then you will looking up to fly if normal eye level is when the monitor is lowered, its not good (I have done it on one design). This may also be vice versa when lowered, looking down, gotta watch your posture now!

 

You definitely want the lower monitor below eye level.

 

Of course you may have an adjustable chair but just a thought, perhaps mock the levels up with books or something to make sure you like it.

 

Other idea I had was to cut a hole in the desk so you could mount your lower monitor lower, perhaps you could put the wood cut from the hole back in to restore your desk and hide most of the lower monitor when not in use?

 

Keep us posted on how you go!

[PiedDroit]

You definitely want the lower monitor below eye level.

The main monitor's upper border should really be at eye level too (otherwise, say hello to neck strain).

IMO the ideal solution is fixed with the lower monitor "buried" into the desk...

Not easy to design but best for the neck.

 

Fixed solution with both monitors stacked from desk level would work only with rather small monitors.

[doveman]

I think it'll be OK with the upper monitor's bottom half around eye level, as I'll only be displaying the exterior view on it, so if the HUD area is in the lower half that's where the focus will be most of the time, with the upper half of the monitor showing the overhead panels or sky depending on the aircraft.

 

When I last measured I worked out that I could have 23cm between the desk and the bottom of the monitor for it to be OK for simming. It encourages me to sit up straight as well, which is good for my back :)

 

At the end of the day cutting into the desk is not an option, so I have to do my best to make it work. There's a couple of things I can do to lower the upper monitor a bit, firstly angling the lower monitor more and secondly cutting a recess into the wooden base so that the lower monitor's bottom edge sits in that and resting on the desk, rather than on top of the wooden base but those are only going to reduce the height by so much.

 

Maybe I can use something like this to bolt to the wooden base and then screw a pipe into to serve as the inner pole, which should be quite stable. http://www.jtmplumbing.co.uk/pipe-fittings-c433/flanges-c371/jtm-113pn6-screwed-flange-6-4-pp13523?utm_source=google&utm_medium=cpc&utm_term=jtm-113pn6-screwed-flange-6-4-size-3-4-quot-20mm-4-holes-bolt-size-m-size-3-4-20mm-4-holes-bolt-size-m10-50-not-inc-a4613&utm_campaign=product%2Blisting%2Bads&gclid=COPPyqncl8YCFSIFwwodd0wANw

 

I don't know whether a round pole will be suitable or if I should look for something square though, as that might be less likely to wiggle around. I'll also need to find an outer pole that is bigger than the inner one but not by too much, although maybe I can glue some rubber to one of the poles (at strategic places, there's probably no benefit in covering the entire pole) to make it a tight fit but I don't know how available such rubber might be.

 

EDIT: I'm obviously mistaken about 23cm, that's way too low. Maybe I meant 33cm or even as high as 40cm might be OK.

Edited June 19, 2015 by doveman

[Mr_Burns]

I would give it a test though, those LCD screens can look funny if not at the right angle, I have found myself trying to look over the hud!

 

I tried to make a monitor stand out of steel plumbing pipe, you can get it in B&Q (assume your UK?) and using the connectors to get various shapes including something like that flange you showed, its pretty sturdy stuff and then you could probably get a galvanized steel fence post which will fit over the top, might be a bit noisy adjusting it, perhaps you can line it with a poly tube of similar diameter?

 

Square tube possible easier to work with for the diyer as you can do more precise drilling and create home made brackets to easily screw into it.

 

With regards to being unable to screw into the desk/wall, you could mount it all on a separate piece of wood which sits on to of your desk, providing it is wide enough it will be just as stable.

 

Just add one other thing, sorry about these crappy picture but this is mine:

 

2 x Dell 23 inch above and below config:

 

 

Top on with stand just sits on the "shelf" bottom one without stand is attached to cutout on the shelf:

 

 

The shelf is just a pine board with 4 treated pine legs:

 

 

Make it in 20 minutes, put some carpet tiles on the desk to protect it?

 

I added some home made panels, you can make the shelf wider than the monitors for speakers, panels, cup holders. Probably you 20 quid and be running today.

 

This will give you a good starting platform whilst you think about the pole - its also sturdy as, which monitor mounts (homemade) can be far from!

[doveman]

I should explain I'm actually planning this as a birthday present for my Dad. After that I'll build something for myself which will be easier as I can do whatever I like to my desk but he has an expensive heavy one that he's quite fond of and I wouldn't dare mess with!

 

The upper Benq 27" monitor is a VA and the lower Dell 22" an IPS, which I specifically chose for it's better viewing angles than TN panels to give me some room for manoeuvre with the angle. Being adjustable will allow me to find the best compromise between the height of the upper monitor and the angle of the lower monitor and I'll just need to drill some extra holes in the poles to provide some options in that respect, although it will obviously be better if I can find the ideal setting and only drill one hole.

 

It will need to be adjustable for my Dad as he currently has the Benq on it's stand, which puts the lower bezel only 115mm above the desk and he's got used to that but it's not really ergonomic at that height and I intend to have it sit a bit higher when the stand is in the lowered position (I'm thinking about 170mm, the drawing I did in Rhino only has it 97mm above the desk) and I'm sure he'll appreciate this height is better once he experiences it. In theory I could position the Dell monitor at the height he currently has the Benq and fix the BenQ in the raised position but that would put it too high for him to use comfortably for non-simming purposes and would mean he'd have to use the 22" Dell for normal use, which is a non-starter as his eyesight isn't as good as it used to be, so he needs to use the larger monitor (and increased DPI). I've got the VESA brackets, one that's tiltable for the Benq so that he can tweak it to suit and another that's fixed for the Dell.

 

One difficulty is in not knowing the exact position of the VESA holes on the Benq. I'd assume they're in the centre of the monitor but I don't know if that can be relied on, so I might have to try and take a sneaky measurement when my Dad's not looking. Then, once I've got the hardware for the stand, I can use some cardboard as placeholders for the monitors to work things out.

 

I am planning to use a wooden base, something thick and heavy to help keep it all stable. That pine board you used looks like it would do the trick, what thickness is that?.

 

I came across this design http://techreport.com/forums/viewtopic.php?f=37&t=70862 which isn't anything like what I'm planning but gave me the idea of bolting a threaded flange like this http://www.jtmplumbing.co.uk/pipe-fittings-c433/flanges-c371/jtm-113pn6-screwed-flange-6-4-pp13523?utm_source=google&utm_medium=cpc&utm_term=jtm-113pn6-screwed-flange-6-4-size-3-4-quot-20mm-4-holes-bolt-size-m-size-3-4-20mm-4-holes-bolt-size-m10-50-not-inc-a4613&utm_campaign=product%2Blisting%2Bads&gclid=COPPyqncl8YCFSIFwwodd0wANw to the wooden base and then screwing some threaded pipe into that for the inner pole. It will depend on whether I can get pipe in a slightly bigger diameter to serve as the outer pole though, as well as how it easy it will be to cut the pipe down to size and drill holes in it. As you say, square tube will probably be easier to use and perhaps less likely to have wobble between the inner and outer poles than round tube, so I'm going to keep looking for something suitable.

 

Thanks for the tip about steel piping and galvanised steel fence post. I am in the UK and browsed the Wickes and B&Q sites without finding anything useful but it's obviously hard when you don't know exactly what to look for. I'm a bit worried that anything I line the inner pole with might peel off with repeated movement of the poles but if I can find something that covers the entire pole and that I can fold down inside the top and glue in position, that might help avoid that happening.

 

A steel fence post like this might work https://www.jacksons-fencing.co.uk/product/sc_073068/euroguard-post-60x40-for-1.8m-high-fence-galvanized.aspx?tpc=BA&fmc=AM&fnc=AX&timber=0 but I'd need to be able to cut it down to about 40cm. Assuming it's hollow, then I could slip it over something slightly smaller but I'm not sure there is anything suitable available. A fence post support like this http://www.ebay.co.uk/itm/HEAVY-DUTY-GALVANISED-BOLT-DOWN-SQUARE-FENCE-POST-FOOT-SUPPORT-ANCHOR-2mm-THICK-/221802184296 screwed/bolted to the wooden base isn't high enough to serve as the inner pole but maybe I could attach a steel post to that and then a bigger steel post could slide over it. That's starting to get quite expensive though.

 

This place has mild steel box section http://www.themetalstore.co.uk/products/1-5-metre-lengths-box-section-2mm and offcuts here http://www.themetalstore.co.uk/products/metal-offcuts-mild-steel-box-section in various sizes. They get a bit expensive in the larger sizes but maybe a 20mmx20mmx2mm (or 2.5mm in the offcuts) for the inner pole and a 25mmx25mmx2mm (or 2.5mm) for the outer pole would work. That's quite small though, so I'm not sure it would be robust enough to take the weight of two monitors. Besides being expensive, the larger sizes mostly step up by 10mm, which might leave too much space between the poles if I don't coat the inner pole with something. They also sell steel angle, so I could use four small pieces of that to secure the inner pole to the wooden base http://www.themetalstore.co.uk/products/1-5-metre-lengths-3mm-angle but I've probably already got some angle brackets I could use for that and if not, it's probably cheaper to buy some than the steel angle.

 

I like what you've come up, nice and simple and cheap as well. :thumbup: Unfortunately it's not suitable for my Dad but it might be something I can use when I come to building my own stand.

[Mr_Burns]

If you know the benq model you might be able to find a schematic on line for the vesa location.

 

I cut out some ply and mdf blocks to fit to the vesa mount, you will need some longer screws but they are available in b&q type places. What this gives you is the ability to screw other wood and brackets to monitor so you don't need vesa location holes. You can use pipe clamps (look like the omega sign) I lined them with garden hose for a snug fit.

 

This way you could use 2x2.5mm if you were worried about the weight?

 

That was 2cm pine, it was for a shelf in my daughters room by needs were more.

Edited June 21, 2015 by Mr_Burns

[hannibal]

i found this type of monitor situation gives better performance than 3 monitors in 5040x1080

[Mr_Burns]

Im sure he wont mind me using his pic, this is hegykc who is making these, look on the Input thread under F18 Grip.

 

Look at the stick design, it has a square steel and adjustable, I know its not holding a monitor and its only a render but you can buy those locking nuts to hold it.

 

What about this:

 

http://www.diy.com/departments/varnished-steel-square-tube-h25mm-w25mm-l2m/254156_BQ.prd

 

25mm square steel, 2 meter length, but the product below it is 20mm, that should fit nicely inside. They also sell plastic square fittings so you could make like a frame so its a bit more sturdy.

 

You could cut say 2 x 10cm of 25mm, drill them to fit a locking bolt attach them to a piece of wood say 15cm apart and drill the wood with vesa holes so it fits on the back of the monitor.

 

You can then mount 2 x 20cm vertical rails, slide the monitor over, fix off the top of the rails with 2 plastic corners and a 15cm piece of steel tube across the top.

 

I would think that you should either support the vertical bars that the top monitor is running on where your 'runners' do need to run.

 

Wow hard to explain, but lets say you vertical bar is 50 cm from desk to top, but the lowest point the monitor slides down to is 10 cm from the desk, make sure you pack them out with wood. I think it will really help with the stability.

 

I recon if you waxed the bar they will be ok but you may be able to wrap them in some adhesive tape to pack it?

[Mr_Burns]

i found this type of monitor situation gives better performance than 3 monitors in 5040x1080

 

I agree with this, had 3 x 23 and a 18 inch, it zapped my performance, I loved it, but to be honest with a track-ir, I rarely used much of the 2 outside screens. Im going to get a bigger main screen eventually, because they are the same size but one is behind the other it looks like the lower screen is bigger than the top one.

 

Still framerates went up to 60. :joystick:

[hannibal]

I agree with this, had 3 x 23 and a 18 inch, it zapped my performance, I loved it, but to be honest with a track-ir, I rarely used much of the 2 outside screens. Im going to get a bigger main screen eventually, because they are the same size but one is behind the other it looks like the lower screen is bigger than the top one.

 

Still framerates went up to 60. :joystick:

 

exactly. what is the point of triple screen if you have to put all you gfx settings on low.

those dudes with the 3 project setup, i think its cool to sit in, but horrible to play...

[doveman]

If you know the benq model you might be able to find a schematic on line for the vesa location.

 

I cut out some ply and mdf blocks to fit to the vesa mount, you will need some longer screws but they are available in b&q type places. What this gives you is the ability to screw other wood and brackets to monitor so you don't need vesa location holes. You can use pipe clamps (look like the omega sign) I lined them with garden hose for a snug fit.

 

This way you could use 2x2.5mm if you were worried about the weight?

 

That was 2cm pine, it was for a shelf in my daughters room by needs were more.

 

lol, yeah cockpit always takes priority over kid's shelf to put random junk on :)

 

Thanks, I'll get some 2cm pine then. I've realised there's a major issue with my design, so I'll knock up a picture to show it and an alternative idea.

[doveman]

Im sure he wont mind me using his pic, this is hegykc who is making these, look on the Input thread under F18 Grip.

 

Look at the stick design, it has a square steel and adjustable, I know its not holding a monitor and its only a render but you can buy those locking nuts to hold it.

 

What about this:

 

http://www.diy.com/departments/varnished-steel-square-tube-h25mm-w25mm-l2m/254156_BQ.prd

 

25mm square steel, 2 meter length, but the product below it is 20mm, that should fit nicely inside. They also sell plastic square fittings so you could make like a frame so its a bit more sturdy.

 

You could cut say 2 x 10cm of 25mm, drill them to fit a locking bolt attach them to a piece of wood say 15cm apart and drill the wood with vesa holes so it fits on the back of the monitor.

 

You can then mount 2 x 20cm vertical rails, slide the monitor over, fix off the top of the rails with 2 plastic corners and a 15cm piece of steel tube across the top.

 

I would think that you should either support the vertical bars that the top monitor is running on where your 'runners' do need to run.

 

Wow hard to explain, but lets say you vertical bar is 50 cm from desk to top, but the lowest point the monitor slides down to is 10 cm from the desk, make sure you pack them out with wood. I think it will really help with the stability.

 

I recon if you waxed the bar they will be ok but you may be able to wrap them in some adhesive tape to pack it?

 

It's funny that you suggest using rails, as that's what I thought of when I realised the problem with my first design.

 

I've cloned the inner pole (green) behind the moving one in these pictures so that you can see the problem better and I've marked a variety of desk->bottom of monitor distances. With the monitor in the lowest position, roughly 97cm above the desk, the inner bar can only go up as high as the wood and bolt in the moving pole.

 

So then, when the moving pole is raised so that the monitor is roughly 300mm above the desk, there's barely any of the inner pole supporting it. It would be impossible to go as high as 350mm, as then it would be off the inner pole completely!

 

If the lowest the monitor goes is 170mm off the desk, then I can use a longer inner pole (red)

 

but when I raise the monitor to 350mm there's still barely any of the inner pole supporting the moving pole

 

So, for the alternative design I thought of having two fixed poles either side of the moving pole, with rails on the poles so that the moving pole slides up and down on those.

 

It does mean you'll see the two fixed poles poking above the monitor when it's in the lowered position but that's OK and the maximum height of the monitor is only constrained by how high I make the fixed poles. 500mm is enough for them, so I'd get two out of a 1m piece.

 

You suggested some steel tube but I wonder if aluminium would be strong enough, as I can get 1m of that in 20x20x2mm for about £8 or £9 for 25x25x2mm? Other sizes and lengths are available at reasonably stepped prices as well but I don't want to waste money buying something that's completely unsuitable. The moving pole will need to be slightly smaller than the outer poles and if that needs to be a certain size to support the weight of both monitors, then the outer poles will need to be the next size up from that.

 

A locking bolt might be a good idea. Even with the new design maybe I could find one long enough to go through all three bars from the side, otherwise I could have put it through the front of the moving pole somewhere below the monitor and have a fixed plate that spans the two outer poles at the back, with a hole in it for the locking bolt to go into. I'd just have to position the fixed plate at the right position so that the holes lines up when the monitor's in the raised position.

 

I'm not sure where I'd get the rails from though. They might not need to run the whole length of the poles, maybe just the middle 2/4 so that the moving pole is at least partly on the rails in both the lowered and raised position. I thought I might be able to get some kitchen drawer rails but I'm not sure they'd be long enough.

 

The moving pole won't need to be as long as before and doesn't need to come down to touch the base, as I can secure a piece of wood between the outer poles and raised above the base which it will rest on in the lower position, maybe with a recess cut into it for the pole to sit in. That means the wooden base around the outer poles is clear and I can fit L brackets on each side to hold the outer poles, although there might not be space between them for a bracket for both on those sides. Maybe brackets on just three sides would hold them secure, otherwise I'll have to think of a way of securing the fourth side as well. I could fit further plates at different heights on the back spanning both outer poles to join them together, which should help stablise them.

 

Another benefit with this design is that I can attach the mounting hardware for the lower monitor to the moving pole, rather than having to attach it to the bolt at the top behind the VESA bracket. Whilst I haven't worked out what I could use for this yet, it should still be less complicated.

 

I'm not sure if any of this is what you were suggesting because it's hard to convey a design in words as you say but please keep the suggestions coming as I'm just throwing ideas out at the moment, I don't know if they'll be practical and there may well be a better way of doing things.

Edited June 22, 2015 by doveman

[doveman]

Perhaps one of these would work for the rails?

 

http://www.gsf-promounts.com/r21d-150mm-45kg-pr/

 

http://www.gsf-promounts.com/solar-length-300mm-extn-365mm-lock-out-detach-60kg-pr/

 

http://www.gsf-promounts.com/flexfit-1529-modular-system-steel-rail/

 

or more expensive but I could collect and I don't know what gsf charge for P&P:

 

http://www.screwfix.com/p/ball-bearing-drawer-runners-500mm/55282

 

http://www.screwfix.com/p/soft-close-ball-bearing-drawer-runners-450mm/48173

[Mr_Burns]

Yeah drawer runners is a good idea. I just picked up some from our local DIY shop for a CNC im building, they are really sturdy.

 

The way ive done mine is to put them either side of a square length of wood. This wood could make up the back of your stand.

 

Then I made a U piece from MDF, the two sides of the U connect to the drawer slides and you attach your monitor to the flat bit. You could drill a couple of holes in the wood and use a lock ot something to hold it at different levels.

 

Problem with that would the pole would have to be as high as the uppermost position. Unless you could lock it from underneath.

 

This is a really small pic, its not mine, but see how this is, instead of the bit that goes up and down one here (the Z axis) im thinking reverse it, so that bit in the middle is the Post and the U shaped bit that is on the axis that moves left to right moves up and down.

 

[doveman]

Yeah drawer runners is a good idea. I just picked up some from our local DIY shop for a CNC im building, they are really sturdy.

 

The way ive done mine is to put them either side of a square length of wood. This wood could make up the back of your stand.

 

Then I made a U piece from MDF, the two sides of the U connect to the drawer slides and you attach your monitor to the flat bit. You could drill a couple of holes in the wood and use a lock ot something to hold it at different levels.

 

Problem with that would the pole would have to be as high as the uppermost position. Unless you could lock it from underneath.

 

This is a really small pic, its not mine, but see how this is, instead of the bit that goes up and down one here (the Z axis) im thinking reverse it, so that bit in the middle is the Post and the U shaped bit that is on the axis that moves left to right moves up and down.

 

 

Yeah, it's a bit hard to see anything from that pic. Maybe I understand what you're getting at though. It looks like there's a piece of wood at the back with two pieces attached to that and projecting forward either side to which the rails are attached (is this what you mean by the U shape?). In between those is a rectangular piece of wood with the other part of the rails attached and I would attach the monitor to this movable piece of wood in the middle.

 

This first picture shows the wooden back piece (purple) and the side pieces/rails (white). I've drawn them like that as originally I thought of just screwing this type of base fixed runner http://www.ironmongerydirect.co.uk/products/cabinet_furniture_and_hardware/runners_and_cabinet_systems/438003/blum_base_fixed_drawer_runners_single_extension_cream/789003 into the wooden back piece, so the part that normally screws into the underside of the drawer would be screwed into the wood , with the rail side facing inwards towards the movable tubing, to which the other part of the rail would be attached. The wooden back piece is 500mm and the rails 450mm, as I don't think they need to be as long as the back piece.

 

 

This second picture shows the movable tubing (red), with the monitor attached to a VESA bracket, which is screwed to a piece of wood (blue), which is bolted through the tubing. Whilst this might be OK, it might hold the monitor more securely if I use a shaped piece of wood that fits into the top of the tubing as I did with the previous design. I think hardwood might be better than MDF for this, as there's less risk of the screws pulling out. With the monitor in the lowest position (100mm above the desk), the movable tubing sits slightly below the fixed rails but that's OK, I'll just need to mount the rails slightly up from the end of the movable tubing so that they start in line with the fixed rails. I'll probably make the lowered position higher than that anyway, so it won't be an issue. I'm thinking of using soft-close runners like these (£5.49/pair 450mm) http://www.ebay.co.uk/itm/SOFT-CLOSE-RUNNER-DRAWER-RUNNERS-FULL-EXTENSION-BALL-BEARING-SLIDE-PAIR-PKL/200782128364?_trksid=p5411.c100170.m2943&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140131123831%26meid%3Dffb25237aa9948b1b200d7d1162e7e42%26pid%3D100170%26rk%3D4%26rkt%3D15%26mehot%3Dpp%26sd%3D291108229942 as they should help prevent damage to the monitor if someone accidentally lets go of it whilst adjusting it.

 

In the raised position, the movable tubing will sit slightly above the runners but that shouldn't matter but if it does I'll have to use 500mm runners. The green part under the monitor is a piece of wood or strip of metal attached to the movable pole, to which hardware can be attached to mount the lower monitor. Under the shelf will be a hole in the movable tubing, with a matching hole in the wooden back piece for a pin or bolt to go through to hold the stand in the raised position.

 

I'll have to be mindful that the weight of the monitors are at the front. Whilst the runners themselves are able to support 30kg, which is much more than the weight of both monitors, the weak point will be where the runners are attached to the wood (and possibly the movable tubing). Also the screw points for the runners are in the same position on both sides, so I'll need the movable tubing to be wide enough so that it can accommodate screws from both sides without them clashing.

 

There may be less risk of problems if I stick with attaching the rails to fixed tubing either side of the movable tubing rather than screwing the rails to a piece of wood at the back. The fixed tubing will need to be secured to the wooden base but L brackets on all four sides should hold those firm. I was actually thinking of replacing the bracket at the front with a hinge, so that the two fixed poles could be folded forward flat against the wooden base, which would make it easier for transporting. The three L brackets for the other sides would remain screwed to the wooden base and then screwed into the fixed poles when they're raised into position (again I need them wide enough to be able to do this without the screws clashing).