Shelves

Bendy_House

All good info above.

The sequence in choosing these sizes of fixings will start with the screw - how thick does it need to be? Usually 4 to 5mm will cover most bases. You then choose the plastic plug to suit the screw, and the masonry drill bit to suit the plug (the plug will state all the sizes it'll cope with).

For your shelf, the sizes suggested above - ~4.5 to 5mm screws with brown plugs sound good.

The screw should go roughly 2" into a solid wall, maybe slightly less. That means the hole to be drilled should be a bit deeper again - by at least 5mm or more, since the screw must not bottom-out.

The plug should be inserted well into the hole, certainly below surface level. The layer of plaster (~half-inch) over the blocks won't be doing much of the holding, and is also prone to crumbing around the hole if the plug is too near the surface and expands there when the screw goes in. So, drill the hole the required depth (wrap tape around the drill bit as a depth-gauge), insert the bare screw and use it to catch and remove all the dust and debris in the hole (or use a straw to blow it clean, but close your eyes...), and then insert the plug and tap it down until flush with the wall. Place the screw in it, but don't turn it. Gently tap the end of the screw to try and get the plug as far into the hole as you can, ideally a good few mm below surface level at least.

Screw. The screw should feel firm to turn once it's getting over half-way in there - that's the sign of a good grip. If they are tight to turn, then coat the screw thread with oil - even cooking oil.

First, tho', mark out carefully and level where - exactly - the holes need to be drilled. You can use a screw & hammer to tap a wee starting dint in the wall - the drill bit will be less likely to wander. Hold the drill level, and nicely firm so you are preventing it from wandering under its own weight. If you find that the drill wanders off course once it hits the blocks under the plaster layer, it may be that the concrete used is just too hard (pebbles, etc) for a normal hammer drill. An SDS drill (from around £50) will make easy work of this.

SavingStudent1

grumbler said:

SavingStudent1 said:

I am planning to do this: get a screw, e.g. 5 mm thick, get the wall plug of the same thickness so the screw is not loose in the wall plug.

The plug is always thicker. You need 7mm masonry drill bit for brown one.

Then, use a drill bit of the same thickness to create a hole that is the same thickness, so the wall plug won't be loose and will fit right in and be tight.

1. By the way, why you a wall plug be loose in the hole? 

Because mortar between bricks is not as strong as bricks. Even worse, you can be unlucky to hit the edge of a brick and the drill bit will go towards mortar while you need the second hole in a precise position. It's worth using a smaller drill bit first, 6mm in this case, and then use 7mm only if needed.

2. How do you sort of know if you drilled a hole say 45m deep, do you just drill and put the wall plug in and see if you need more space etc.?

Make a mark on the drill bit first or extract it from the hole and compare to the screw. Nothing wrong if the hole is deeper than needed. If the hole diameter is perfect you normally can't just put the plug into it and need a hammer.

I drew this to show what it'll be like. I feel 10 mm is enough right? Because, if I get too long of a screw compared to the wall plug, e.g. 70 mm for a 40 mm wall plug, then the screw will stick out too much and the wall shelf won't be flat against the wall, but rather it will be hanging like the blue one. The black one is original - it is against the wall, but the blue one is not against the wall as it won't go in fully. I am going off the image on the website where they had the screws sticking out by a bit - probably about the depth of the bracket ~ 10 mm, I assume?

I don't understand the picture, but for this sort of fixing the distance that the screw sticks out of the wall is a matter of trial and error. Make it smaller gradually until the shelf hangs tightly.  The hole depth has to be the same as the screw length or bigger.

Okay, so let's say I get a screw of 5 mm diameter/thickness, wall plug of 7 mm diameter/thickness (brown). Then, do I need to get a drill bit of higher thickness/diameter than the wall plug right, so either 7mm or more - but not too much more, else it'll be loose? But, in your case, since you say 6 mm drill bit first - I assume the wall plug will be of 5-6 mm diameter/thickness.

Also, if I drill a deep hole with 6 mm drill bit, then using a 7 mm one after to create a larger hole - will it not affect the surroundings or will it just create a normal hole still despite drilling in a hole area?

Oh right, yes - I forgot the drill bit goes inside the wall as you drill a hole lol, so that makes sense now!

Oh okay, so in terms of "making it smaller" - the distance that the screw sticks out of the wall, this can really be done in two ways only right?

1. Increasing the length of the wall plug i.e. getting a longer wall plug, or 2. decreasing the length of the screw i.e. getting a shorter screw?

SavingStudent1

Bendy_House said:

All good info above.

The sequence in choosing these sizes of fixings will start with the screw - how thick does it need to be? Usually 4 to 5mm will cover most bases. You then choose the plastic plug to suit the screw, and the masonry drill bit to suit the plug (the plug will state all the sizes it'll cope with).

For your shelf, the sizes suggested above - ~4.5 to 5mm screws with brown plugs sound good.

The screw should go roughly 2" into a solid wall, maybe slightly less. That means the hole to be drilled should be a bit deeper again - by at least 5mm or more, since the screw must not bottom-out.

The plug should be inserted well into the hole, certainly below surface level. The layer of plaster (~half-inch) over the blocks won't be doing much of the holding, and is also prone to crumbing around the hole if the plug is too near the surface and expands there when the screw goes in. So, drill the hole the required depth (wrap tape around the drill bit as a depth-gauge), insert the bare screw and use it to catch and remove all the dust and debris in the hole (or use a straw to blow it clean, but close your eyes...), and then insert the plug and tap it down until flush with the wall. Place the screw in it, but don't turn it. Gently tap the end of the screw to try and get the plug as far into the hole as you can, ideally a good few mm below surface level at least.

Screw. The screw should feel firm to turn once it's getting over half-way in there - that's the sign of a good grip. If they are tight to turn, then coat the screw thread with oil - even cooking oil.

First, tho', mark out carefully and level where - exactly - the holes need to be drilled. You can use a screw & hammer to tap a wee starting dint in the wall - the drill bit will be less likely to wander. Hold the drill level, and nicely firm so you are preventing it from wandering under its own weight. If you find that the drill wanders off course once it hits the blocks under the plaster layer, it may be that the concrete used is just too hard (pebbles, etc) for a normal hammer drill. An SDS drill (from around £50) will make easy work of this.

Thank you, this really helps.

1. What do you mean by "screw must not bottom-out"?

2. What do you mean by "surface level" in this context?

3. Should the hole be drilled 5 cm (I assume you meant cm instead of mm) deeper than the length of the screw or the wall plug?

Thanks for the tips regarding the drill wandering, this was one of my main concerns as I don't want to drill a line instead of a hole lol.

grumbler

SavingStudent1 said:

grumbler said:

SavingStudent1 said:

I am planning to do this: get a screw, e.g. 5 mm thick, get the wall plug of the same thickness so the screw is not loose in the wall plug.

The plug is always thicker. You need 7mm masonry drill bit for brown one.

Then, use a drill bit of the same thickness to create a hole that is the same thickness, so the wall plug won't be loose and will fit right in and be tight.

1. By the way, why you a wall plug be loose in the hole? 

Because mortar between bricks is not as strong as bricks. Even worse, you can be unlucky to hit the edge of a brick and the drill bit will go towards mortar while you need the second hole in a precise position. It's worth using a smaller drill bit first, 6mm in this case, and then use 7mm only if needed.

2. How do you sort of know if you drilled a hole say 45m deep, do you just drill and put the wall plug in and see if you need more space etc.?

Make a mark on the drill bit first or extract it from the hole and compare to the screw. Nothing wrong if the hole is deeper than needed. If the hole diameter is perfect you normally can't just put the plug into it and need a hammer.

I drew this to show what it'll be like. I feel 10 mm is enough right? Because, if I get too long of a screw compared to the wall plug, e.g. 70 mm for a 40 mm wall plug, then the screw will stick out too much and the wall shelf won't be flat against the wall, but rather it will be hanging like the blue one. The black one is original - it is against the wall, but the blue one is not against the wall as it won't go in fully. I am going off the image on the website where they had the screws sticking out by a bit - probably about the depth of the bracket ~ 10 mm, I assume?

I don't understand the picture, but for this sort of fixing the distance that the screw sticks out of the wall is a matter of trial and error. Make it smaller gradually until the shelf hangs tightly.  The hole depth has to be the same as the screw length or bigger.

Okay, so let's say I get a screw of 5 mm diameter/thickness, wall plug of 7 mm diameter/thickness (brown). Then, do I need to get a drill bit of higher thickness/diameter than the wall plug right, so either 7mm or more - but not too much more, else it'll be loose? But, in your case, since you say 6 mm drill bit first - I assume the wall plug will be of 5-6 mm diameter/thickness.

A brown plug is slightly bigger than 7mm, not smaller. It makes no sense to drill a hole bigger than 7mm in diameter.

Oh okay, so in terms of "making it smaller" - the distance that the screw sticks out of the wall, this can really be done in two ways only right?

1. Increasing the length of the wall plug i.e. getting a longer wall plug, or 2. decreasing the length of the screw i.e. getting a shorter screw?

For 50mm screw the hole is 50mm+. The plug is shorter than 50mm and the screw can go through it if needed.

getmore4less

https://www.ikea.com/gb/en/assembly_instructions/lack-wall-shelf-white__AA-200208-13.pdf

What are you planning to put on this?

it says max load 3kg,  just about any wall fitting should be fine for that it will be the bracket on the shelf that's the weak point as it is a slot over.

the staring point is the slot the screws will use on page 4

More substantial floating shelves use a different method where the bracket is fixed tight to the wall and the shelf slide on.

SavingStudent1

grumbler said:

SavingStudent1 said:

grumbler said:

SavingStudent1 said:

I am planning to do this: get a screw, e.g. 5 mm thick, get the wall plug of the same thickness so the screw is not loose in the wall plug.

The plug is always thicker. You need 7mm masonry drill bit for brown one.

Then, use a drill bit of the same thickness to create a hole that is the same thickness, so the wall plug won't be loose and will fit right in and be tight.

1. By the way, why you a wall plug be loose in the hole? 

Because mortar between bricks is not as strong as bricks. Even worse, you can be unlucky to hit the edge of a brick and the drill bit will go towards mortar while you need the second hole in a precise position. It's worth using a smaller drill bit first, 6mm in this case, and then use 7mm only if needed.

2. How do you sort of know if you drilled a hole say 45m deep, do you just drill and put the wall plug in and see if you need more space etc.?

Make a mark on the drill bit first or extract it from the hole and compare to the screw. Nothing wrong if the hole is deeper than needed. If the hole diameter is perfect you normally can't just put the plug into it and need a hammer.

I drew this to show what it'll be like. I feel 10 mm is enough right? Because, if I get too long of a screw compared to the wall plug, e.g. 70 mm for a 40 mm wall plug, then the screw will stick out too much and the wall shelf won't be flat against the wall, but rather it will be hanging like the blue one. The black one is original - it is against the wall, but the blue one is not against the wall as it won't go in fully. I am going off the image on the website where they had the screws sticking out by a bit - probably about the depth of the bracket ~ 10 mm, I assume?

I don't understand the picture, but for this sort of fixing the distance that the screw sticks out of the wall is a matter of trial and error. Make it smaller gradually until the shelf hangs tightly.  The hole depth has to be the same as the screw length or bigger.

Okay, so let's say I get a screw of 5 mm diameter/thickness, wall plug of 7 mm diameter/thickness (brown). Then, do I need to get a drill bit of higher thickness/diameter than the wall plug right, so either 7mm or more - but not too much more, else it'll be loose? But, in your case, since you say 6 mm drill bit first - I assume the wall plug will be of 5-6 mm diameter/thickness.

A brown plug is slightly bigger than 7mm, not smaller. It makes no sense to drill a hole bigger than 7mm in diameter.

Oh okay, so in terms of "making it smaller" - the distance that the screw sticks out of the wall, this can really be done in two ways only right?

1. Increasing the length of the wall plug i.e. getting a longer wall plug, or 2. decreasing the length of the screw i.e. getting a shorter screw?

For 50mm screw the hole is 50mm+. The plug is shorter than 50mm and the screw can go through it if needed.

Oh okay, I didn't know the screw can actually go through the wall plug as it looked closed, but I assume if you push hard enough, it will break through.

Cool, so we have in general:

- Choose the screw thickness according to the slot of the bracket that you have to put the screw into.
- Choose the wall plug slightly thicker than the screw, so if you get a 5 mm screw, you should get a ~ 6 mm or ~ 7 mm wall plug (red or brown).
- Choose the drill bit according to the wall plug thickness, make sure you drill a hole 1 mm less or of the same thickness. So, if we choose a brown wall plug ~ 7mm, start off with a smaller drill bit of 6 mm and if the wall plug doesn't fit, then re-drill the hole using 7 mm thickness drill bit, but never larger than the wall plug thickness.
- Always ensure the hole drilled is deeper/longer than the screw's length, so that you have space for the screw in case you need to fully place it in. The wall plug will not be as long as the hole, but the screw may be nearly as long. The screw can go through the wall plug to get it deeper into the hole, so it doesn't stick out as much, if needed - and this is why the hole must be greater than or equal to the screw length for this to happen.

SavingStudent1

getmore4less said:

https://www.ikea.com/gb/en/assembly_instructions/lack-wall-shelf-white__AA-200208-13.pdf

What are you planning to put on this?

it says max load 3kg,  just about any wall fitting should be fine for that it will be the bracket on the shelf that's the weak point as it is a slot over.

the staring point is the slot the screws will use on page 4

More substantial floating shelves use a different method where the bracket is fixed tight to the wall and the shelf slide on.

Yeah, this is why I found this unusual lol as the bracket slides on the screws, rather than there being a bracket attached to the wall and the shelf slides over it. But yeah, took a gamble lol!

I am probably planning to put light items on it, so it is more for decorative purposes and I won't use the full load. I just want it to look good really, so I am trying to learn how to do it effectively.

grumbler

getmore4less said:

https://www.ikea.com/gb/en/assembly_instructions/lack-wall-shelf-white__AA-200208-13.pdf

it says max load 3kg,  just about any wall fitting should be fine for that it will be the bracket on the shelf that's the weak point as it is a slot over.

Well, for this design the lever is huge and is the main factor. It works almost like a crowbar.

For this particular shelf 3kg load close to the edge can produce about 3*30/2.5=36kg force pulling the plugs out of the wall.

FreeBear

SavingStudent1 said:  - Choose the drill bit according to the wall plug thickness, make sure you drill a hole 1 mm less or of the same thickness. So, if we choose a brown wall plug ~ 7mm, start off with a smaller drill bit of 6 mm and if the wall plug doesn't fit, then re-drill the hole using 7 mm thickness drill bit, but never larger than the wall plug thickness.

When drilling holes, I'll often start with a 3mm or 4mm drill - It makes it much easier to get the hole on the mark. Go in with a 6mm drill to the full depth required, and then use a 7mm to bring it to size. Trying to do it with just a 7mm drill (or even a 6mm) invariably means the hole ends up being in the wrong place and bigger than intended.

Bendy_House

SavingStudent1 said:

Bendy_House said:

All good info above.

The sequence in choosing these sizes of fixings will start with the screw - how thick does it need to be? Usually 4 to 5mm will cover most bases. You then choose the plastic plug to suit the screw, and the masonry drill bit to suit the plug (the plug will state all the sizes it'll cope with).

For your shelf, the sizes suggested above - ~4.5 to 5mm screws with brown plugs sound good.

The screw should go roughly 2" into a solid wall, maybe slightly less. That means the hole to be drilled should be a bit deeper again - by at least 5mm or more, since the screw must not bottom-out.

The plug should be inserted well into the hole, certainly below surface level. The layer of plaster (~half-inch) over the blocks won't be doing much of the holding, and is also prone to crumbing around the hole if the plug is too near the surface and expands there when the screw goes in. So, drill the hole the required depth (wrap tape around the drill bit as a depth-gauge), insert the bare screw and use it to catch and remove all the dust and debris in the hole (or use a straw to blow it clean, but close your eyes...), and then insert the plug and tap it down until flush with the wall. Place the screw in it, but don't turn it. Gently tap the end of the screw to try and get the plug as far into the hole as you can, ideally a good few mm below surface level at least.

Screw. The screw should feel firm to turn once it's getting over half-way in there - that's the sign of a good grip. If they are tight to turn, then coat the screw thread with oil - even cooking oil.

First, tho', mark out carefully and level where - exactly - the holes need to be drilled. You can use a screw & hammer to tap a wee starting dint in the wall - the drill bit will be less likely to wander. Hold the drill level, and nicely firm so you are preventing it from wandering under its own weight. If you find that the drill wanders off course once it hits the blocks under the plaster layer, it may be that the concrete used is just too hard (pebbles, etc) for a normal hammer drill. An SDS drill (from around £50) will make easy work of this.

Thank you, this really helps.

1. What do you mean by "screw must not bottom-out"? The screw tip mustn't reach the bottom of the hole before it's done its job - securing whatever. If the screw tip hits the bottom of the hole, then (a) if cannot go any further so you may not be able to tighten up whatevere it is you are fixing, and (b) it'll try and force out the plug by it being 'screwed' back up the screw shaft.

2. What do you mean by "surface level" in this context? The top surface level of the wall. The best part of 10-15mm depth of what you see in front of you will be plaster. Plaster isn't that strong, so however much of the plastic plug remains in that layer won't be doing much holding. If you insert a 40mm-long plastic plug into a solid wall like yours, and stop when the top edge reaches the wall surface, then ~15mm of that plug will still be in that plaster layer, and only 25mm will be soldily located in the hard block wall behind it. 25mm isn't much, at least not if you want a really firm fixing. So, for a 40mm plug, drill the hole a good 60+mm deep, clean out the hole, and try and tap the plug right in so it's well below surface level.

3. Should the hole be drilled 5 cm (I assume you meant cm instead of mm) deeper than the length of the screw or the wall plug? If you drill the hole 5cm (50mm) deeper than the screw length, then chances are you'll end up in the next room. So, yes, I did mean drill the hole around 5mm MORE than the max distance the screw will go in. After you drill the hole, place the screw fully into it (without the plug). You want the screw to either go all the way in so the screw head lands on the wall surface, or you at least want the screw head to be sticking no further out than when it's actually doing its intended job. For instance, if you were going to be screwing a timber batten to the wall, and this batten was 20mm thick, then the screw would have to be able to sit in that hole will only 15mm at the very most sticking out. If the screw bottoms out with 20mm of it still sticking out of the wall, clearly it ain't going to be holding that batten tightly to the wall.

Thanks for the tips regarding the drill wandering, this was one of my main concerns as I don't want to drill a line instead of a hole lol. 'Welcome :-)

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