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The weight of the 3 monitors on my 3-monitor arm has destroyed my IKEA table (not real wood). See picture.

I want to still use the same monitor arm with 3 monitors in the same area, where the damage is... How can I reinforce that area that has the hole? Can I use a metal sheet or something? Any other ideas?

enter image description here

UPDATE: As recommended in the answers to this question, I added two plexiglass plates (one above the table and another one below it). Size: 15 x 20 cm x 5 mm = 7.87in x 5.9in x 0.19in. 5EUR each.

It has been working great. Thanks for all the suggestions.

enter image description here enter image description here

John Assymptoth
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    That rather depends on the details of the monitor stand mechanism. However, furniture repair is off topic here. – isherwood May 31 '23 at 21:23
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    Is this just surface/cosmetic damage or is the 'wood' damaged/crack all the way though? Just surface damage, then almost any backing material(1/4 inch plywood) should do to spread the force out. – crip659 May 31 '23 at 21:23
  • I see no holes for screws and no holes in the damaged area of the desk. This must be a clamp on stand. It won't be pretty, but I would add some 1/2 " plywood. A rectangle about 3x the width of the stand base and 2x the depth. If that breaks through the desktop, throw the desk away and get something made of real wood. – RMDman May 31 '23 at 21:31
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    How thick is the table, and if you open the stand's jaw clamp all the way, what's the size of the opening? This is leading to .... if you sandwich the table in a couple of pieces of wood around the clamp, how thick could those pieces be? – jay613 May 31 '23 at 21:39
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    @isherwood we frequently take questions on how to mount heavy objects where special steps are required. TVs on drywall. Chin up bars on false walls. OP does not ask how to repair the table. – jay613 May 31 '23 at 21:42
  • In both your examples, _a house_ is involved. Here it isn't. – isherwood May 31 '23 at 21:56
  • @crip659, RMDman, this is a clamp-on stand; no holes were ever drilled. The "wood" was not damaged all the way through. The stand sunk 0.4 inches (1 cm) into the table... Luckily I noticed it on time because it would have kept sinking. – John Assymptoth Jun 01 '23 at 05:16
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    you could use wood or metal, but i would consider 1/4" plexiglass; it's highly resistant to divots, thin, and won't look as janky. – dandavis Jun 01 '23 at 05:17
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    @dandavis, the plexiglass worked like a charm. Thanks for the idea. (I've updated the initial post with a picture of the "after".) – John Assymptoth Jun 06 '23 at 14:09

2 Answers2

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I'll assume the arm's clamp is big enough to add a 3/4 inch piece of wood above and below the table.

Go to the hardware store and get an off-cut of wood about 3 inches wide and a foot long. This can be 3/4 inch plywood or board or even a foot-long offcut of 2x4 that you saw in half along its thickness. Whatever. You want to end up with two pieces of wood, for free, each 3/4 inch thick and 6x3 inches.

Sandwich the table with the wood, above and below. Glue the wood to the table. If the table is chipboard, also screw it with appropriate screws. If it's a cardboard sandwich just glue it ... but maybe go longer than 6 inches.

Clamp the arm to the wood sandwich.

The glue (and screws) are to prevent the pieces of wood from sliding off when the monitors are moved. The clamp by itself will have rubber pads for that purpose. With the added wood pieces, and without fastening them, the arm could end up sliding its way off the table.

jay613
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    +1. It might not even take a trip to the store. Many things could be used for this, such as halves of an old bamboo cutting board or a couple hardcover books. – isherwood May 31 '23 at 22:00
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    Steel plates would be thinner for similar effect. Through-bolt them to each other outside where the clamp lives. – Ecnerwal May 31 '23 at 22:55
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    @Ecnerwal ya but at $6.49 each they will cost more than the table. :):):). Sorry. – jay613 May 31 '23 at 22:57
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    @jay613, could I try what you mentioned without gluing it? Or do you think that's too much of a risk? – John Assymptoth Jun 01 '23 at 05:19
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    3/4 inch is way thicker than you need for wood, that would be thick/firm enough for cardboard. I would think that c. 6mm plywood would be my choice. – MikeB Jun 01 '23 at 09:05
  • @MikeB,yes I reckon thinner would actually be better here, as it would flex just enough to stop the edges digging in – Chris H Jun 01 '23 at 09:17
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    @JohnAssymptoth three monitors on one arm is risky. Putting that on a cheap hollow table is more risky. I hope it has some weight and is solidly put together so the weight of the monitors don't tip the whole thing over. Mounting that arm on makeshift blocks practically built from Lego is even more risky. So is it risky to not glue the blocks down? I don't know just don't touch the monitors, pay close attention, make sure the mount is not walking its way off the table, make sure other people who aren't trained on the risks cannot enter the room. – jay613 Jun 01 '23 at 11:46
  • I had a desk that was a solid slab of wood sitting on a couple of small cabinets. A monitor on a swing arm, when swung back behind the back of the desk, had enough leverage to tilt and lift the entire slab. Luckily I discovered that on time and screwed it down to the cabinets. With a hollow tabletop and legs that probably don't weigh much, the whole thing is risky. – jay613 Jun 01 '23 at 11:50
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    If it's chipboard I agree 6" would suffice, but it's not. It's honeycomb sandwich. That's why it crushed in the first place. That area of honeycomb (probably 3x3 + maybe an inch beyond, 4x5) is damaged to the point of non-functionality. So now we need much more surface contact area to get that honeycomb to resist crushing, *which it is not designed to do*. Further, our board must be stiff enough to span the dead zone and get out to good material. – Harper - Reinstate Monica Jun 01 '23 at 18:17
  • John - I answered your question in a very focused way, and I hope your accepting my answer is because it answers the question you asked and I also hope you'll take @Harper-ReinstateMonica's advice because it is correct ... your question is misplaced, you should not be hanging three monitors off one arm on a desk made mostly out of paper, even if it had a suitable clamp, which it doesn't. – jay613 Jun 01 '23 at 18:21
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Clamps like that aren't for cheap IKEA desks

Ikea desks look solid, but actually they are two layers of thin veener with a cardboard honeycomb material between them. It looks like this or this.

enter image description here

That's cardboard. It's just not made to resist compression. It is made to resist shear, because it's glued top and bottom. Or is supposed to be... QA varies obviously. When Ikea wants to give you a hard-point for a clamp or mounting, they fill that space with chipboard like the corner there.

All the cantilever load of the monitors rests on the toe of that clamp, where it is putting hundreds of kilograms of force down on the assumption that desk is solid. But there's no "there" there. Nothing for the clamp to actually clamp to.

The only way to make this work is to have a large topside spreader that spreads the load across enough of the desk to engage a whole bunch of those cardboard honeycombs. Even if most of the compressive capacity in that area wasn't already wrecked, More like ... 12x24"? And the stiffener needs to be actually stiff over that distance, does not good if it simply creates another compression hotspot. It would be bonkers.

Nothing against Ikea but their desks are not for this. I recommend not wasting lipstick on a pig and get a solid desk.

Harper - Reinstate Monica
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  • Thanks for the reply. To be fair, the table held many years with a stand for two monitors. Only recently (last 2 months), I switched to a 3-monitor setup, which was too much. I would have probably needed a 3-monitor arm that had 2 columns to support the weight... Oh well, I'll try some of the recommendations here. Let's see where that takes me... – John Assymptoth Jun 01 '23 at 05:24
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    These table tops are surprisingly strong, even though they're only 3mm ply on top with cardboard honeycomb inside. I've stood on them many times, and when I broke up a water-damaged one it took quite a lot of effort. BTW a similar construction is used in many other places as it's got very good strength-to-weight; it's just not great against localised pressure. – Chris H Jun 01 '23 at 09:21
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    A spreader of roughly twice the size of the base would be plenty, even with the damage, because it's the edges that matter. You really don't need something huge - the honeycomb cells are about 20mm so a 2" border gets you >2 cells away and into pristine material. The first couple of paragraphs have enough truth that I haven't downvoted the later statements so strong they're wrong. – Chris H Jun 01 '23 at 09:26
  • Upvoting because there are so many reasons this answer is correct. But if we focus (wrongly) on rectifying the immediate problem, I think the 3x6 solution will move the weakest link elsewhere. Like the whole table toppling over :( – jay613 Jun 01 '23 at 14:44
  • @ChrisH The trick with engineered wood is it's not strong *generally* like natural planks. It's only strong *only in the directions in which it is engineered to be strong*. You can stand on them because the honeycomb is glued at top and bottom - so it makes the piece a truss. But trusses are designed to span, not resist compressive loads between top and bottom chord. Ikea could trivially design these desks to take clamp-on monitor stands, simply by making the back 4-5" out of incompressible solid material. **They didn't**, so no strength there. – Harper - Reinstate Monica Jun 01 '23 at 18:05
  • And don't forget - an area about 3x3" has already been crushed, so it is functionally deleted from the equation. Those clamps need compressive strength, and those honeycombs are optimized for shear, not compression. Ikea has plenty of material strong in compression: particle board. That would just make the desk heavier. Like I say, never intended for monitor clamps. – Harper - Reinstate Monica Jun 01 '23 at 18:11
  • I've got several of these. And opened them up. They're far stronger in compression than you seem to think. The leverage of these brackets visibly concentrates the pressure on the front edge so the top skin has to spread the load (note the OP said it was fine for years with 2 monitors - 3 is probably worse than 50% more because of the lever arm towards the user). I am absolutely certain that a small square of thin ply on top and underneath would solve the problem. Even a hardback book would do – Chris H Jun 01 '23 at 18:18
  • @ChrisH Then maybe you're underestimating the forces. It's not the static weight of the monitors *as if* the monitors' forward-backward CG was right on the clamp. That would be straight downward force on the clamp and I agree that would hold. The problem is, that lever arm with the monitors forward of the clamp. A little lever arm goes a long way when the clamp is only 3" and half of it is on hardboard. That it failed is undeniable. "Worked for years" is cold comfort; so did Champlain Towers South. – Harper - Reinstate Monica Jun 01 '23 at 18:26
  • Of course it is. I'm taking that into account when I talk about 3 monitors being worse than 2, because the side ones tend to be further from the back of the desk. Just bridge the damage by a couple of cells, with something like 6mm ply, and stop worrying. It's easy. Once again, I have some of these. I've even destroyed one (deliberately). I also have a long-arm monitor bracket and a dual monitor bracket, used on light structures – Chris H Jun 01 '23 at 18:31