Shortest possible length for plugs and screws?

[Daniel201666]

I am planning to mount two Bestå shelves (see link 1) on one of my concrete walls. The shelves each weigh just over 8 kg and will be mounted with wall rails (see link 2) from the same series. Which plugs and screws should I use for this? I would prefer to use the shortest screws possible, even if it means I need to use more and/or wider ones. The shelves will never be loaded with items weighing more than 10 kg each.

1 - http://www.ikea.com/se/sv/catalog/products/S59132895/#/S99046848
2 - http://www.ikea.com/se/sv/catalog/products/30284846/

 

[Jocke Best]

Hello, I would have used at least 4 pieces of 25 mm.
http://images.biltema.com/PAXToImageService.svc/article/xlarge/87728
Then it should hold. The moment won't be so strong since the shelf is quite tall. Worse with, for example, the lacquered shelves.

 

[A-Man_08]

I had mounted it with brown plugs and screws adapted for the plugs.

 

[Jocke Best]

I mounted it with a brown plug and a screw suitable for the plug.

Brown plug is great. However, 40 mm. Then two screws are enough with your shelves. If you want to use shorter plugs, you have to double them. In my opinion. Why is the length important if I may ask? Short on drills or thin wall?

 

[Daniel201666]

Thank you for all the answers! The reason I want to use screws as short as possible is because I have a mediocre machine that takes time to drill deep with.

 

[Daniel201666]

Are there any good tables on the load capacity of different screws and plugs?

 

[Jocke Best]

There certainly is, but the much larger difference in what each plug and screw can handle depends on the design of the shelf. Imagine the difference when screwing something into the ceiling. There, the threads carry the weight since the load wants to pull the screw out. A wall-mounted shelf that is very deep but short, like Ikea Lack, wants the load to pull the screw out more than to strain it sideways due to the moment. Since your shelves are quite square, the load will mostly be perpendicular to the screw. In my view, then, you don't need such long screws. If you're only drilling a few holes, you might afford a few extra millimeters to sleep well anyway. Or at least use double the screws.

 

[A-Man_08]

When you agree, do it properly if you're going to put something on the wall anyway.
Maybe your machine is excellent, but you need new drill bits?
5 concrete drills of decent quality don't cost much under 100kr.

 

[ullberg]

Are there any good tables showing what load different screws and plugs can handle?

available in e.g. essve's product sheets, for plastic plug and for nylon plug as two examples.

/U

 

[Daniel201666]

Then I should be able to use the screws with dimensions 4x40 mm together with the accompanying plugs from the linked plug set?

http://www.jula.se/catalog/bygg-och...entsatser/skruvsatser/skruv-pluggsats-302402/

 

[Finndjävel]

Had never used shorter than 40mm in concrete, especially not if it's a question of an old wall. 50mm is usually the minimum recommendation if you are going to fasten something that needs to hold, in your case there's no major load but I probably wouldn't go below 40 for that. Old concrete becomes quite porous and crumbles when you drill into it.

 

[A-Man_08]

Keep in mind to account for the thickness of what you're attaching; the screw should go through the entire plug to handle the full load. If possible, I would use the green ones, but the red plug could also work well. Keep in mind that if you have plaster on the concrete, the plug must go past the plaster, and that screw length should also be taken into consideration.

 

[Daniel201666]

Consider accounting for the thickness of what you're fastening; the screw should go through the entire anchor to handle the full load. If possible, I would use the green ones, but the red anchor could work well too. Remember that if you have plaster on the concrete, the anchor needs to pass the plaster, and that screw length should also be considered.

If I remember correctly, the wall in question has about 1 cm of plaster. Is the red one still suitable? The wall track that the screws are to support is 1 mm thick.

 

[A-Man_08]

Regardless of the plug, it should pass through the plaster.
I would have gone with a larger plug than a red plug.

 

[snuttjulle]

A deeper hole, which is then difficult to make, has much greater strength than the 3 you have made easily because these are only in the plaster. Borrow a proper machine.