Help - screws not catching

lucyplease

We have attached a kitchen pole to our wall, it’s going through tiles and then a dot and dab wall to brick. 

There are 6 brackets and 12 screws but about 4 of the screws aren’t catching and are just spinning when they are fully in. 

These are the screws I got - just wonder if anyone has any idea what it could be or what we could do? I have tried these things but they haven't worked (probably for something else..) next step was to try a thicker or longer screw maybe ? Thanks! 

tacpot12

Blow out the screwholes with a straw. The dust might be acting as a lubricant, a bit like talc. 

If that doesn't work, dip the end of the plastic plug in 5 minute Araldite or Polyfiller (the Araldite will set much more quickly. Polyfiller will need to be left overnight). You'll need quite a bit as you need to be sure that it sets on both the plastic and the wall. Then screw the screws in very slowly the start. Once you are sure the plus is is gripping, you can screw more quickly.  

ThisIsWeird

lucyplease said:

We have attached a kitchen pole to our wall, it’s going through tiles and then a dot and dab wall to brick. 

There are 6 brackets and 12 screws but about 4 of the screws aren’t catching and are just spinning when they are fully in. 

These are the screws I got - just wonder if anyone has any idea what it could be or what we could do? I have tried these things but they haven't worked (probably for something else..) next step was to try a thicker or longer screw maybe ? Thanks! 

That's a reasonable choice of screw, so if they didn't work, there must be a logical reason.

A D&D wall is, as you know, normal brick, with the plasterboard sheet adhered on to it with adhesive 'dabs'. These dabs usually end up around 10mm or less thick, so expect to have a small void of that size behind the p'board. Then there's your tiles - let's estimate a thickness of around 10mm for these, too.

So, you have your wall surface, tiles (10mm), plasterboard ~10mm), dab-void (~10mm) and then solid brick (tho' you might hit soft mortar). That's 30mm before the screw plug begins to grab in something solid. 

So, so, what happened when you drilled? I presume a tricky start as the drill went through the tile(?), followed by an easy path through the soft plasterboard, followed by a 'whoops' as the drill popped through the void, and ending with a bit of proper drilling as it went through the bricks?

What actually happened? And, what size drill bit did you use? (Did it come with the screws?)

And, what then? You passed the screw-with-plug through the hole, and what happened? Did it go all the way through until the screw head met the wall surface?

lucyplease

Thanks both for your replies. 

We can try the poly filler - I can get some tomorrow 

That is pretty much what happened! I have a feeling in the bracket where both screws aren’t catching, we maybe went too far into the brick - can that cause this issue if you drill too far? 

We used a tile drill bit first then switched to a Masonary drill bit, one did come with the screws but we used a better make one we had, both the same size although the one we used looked slightly wider but I don’t think it actually is. 

Also, the screws I got have a little metal bit you put into the raw plug before the screw, guess that’s to reinforce where the plasterboard is? But  I thought the screw had to touch the raw plug to expand it? 

Thanks again ! 

ThisIsWeird

lucyplease said:

Thanks both for your replies.

We can try the poly filler - I can get some tomorrow
That is pretty much what happened! I have a feeling in the bracket where both screws aren’t catching, we maybe went too far into the brick - can that cause this issue if you drill too far?

We used a tile drill bit first then switched to a Masonary drill bit, one did come with the screws but we used a better make one we had, both the same size although the one we used looked slightly wider but I don’t think it actually is.

Also, the screws I got have a little metal bit you put into the raw plug before the screw, guess that’s to reinforce where the plasterboard is? But  I thought the screw had to touch the raw plug to expand it?

Thanks again ! 

Could you explain in more detail what actually happened, and how the drill 'felt' as it went through the layers? 

Could you feel it properly drilling through the brick - ie, the expected resistance?

No, you cannot drill too deep - at least it won't affect how the screw sleeve catches.

You can drill not deep enough, and the screw can bottom-out in the hole, and cannot go any deeper. It'll then tend to 'screw out' the sleeve, forcing it back out the hole.

This new, better, drill you used - was it exactly the same size as the provided drill bit? Are you 100% sure? You think it may have been, but could you confirm, please? If it was even a half-mm larger, it would make the sleeve not bind as well as it should in the hole.

Could you explain the 'little metal bit', please? Any chance of a photo? Edit: Ah, it's a support sleeve, presumably designed to prevent the plasterboard sheet from being pulled inwards as you tighten the screw.

Did you follow the exact required procedure when inserting the screw? Did you:

1) drill the hole as deep as the red plug is long, and around 5-10mm extra? (You can test this by inserting just the screw, and confirming it doesn't bottom-out.

2) Did you blow out the dust in the hole? Awkward, but a trick is to insert a straw right in, and slip a hoover nozzle over the end of the straw, roughly sealing it with your fingers - there will be enough 'suck' to clean the hole of dust.

3) Insert the red plug on its own, tapping it in until completely flush with the p'board surface?

4) Insert the metal sleeve, tapping it in until ditto?

5) Insert screw and screw?

https://www.youtube.com/watch?v=SmVgn19TqL0&t=96s

flashg67

If you have concrete blocks behind rather than brick, these can crumble and not hold the wall plugs - there are special ones available, but filling the hole with an epoxy glue then the plug is worth a try,

FreeBear

I've had good results with resin fix when trying to fix stuff to less than perfect walls. A bit expensive when you just have a couple of screws that are iffy.

A selection here - https://www.screwfix.com/c/screws-nails-fixings/injection-resin/cat7440007

Also used No-Nails type grab adhesive injected in to the hole a couple of times for screws that were not under any great load.

vacheron

lucyplease said:

Thanks both for your replies. 

We can try the poly filler - I can get some tomorrow 

That is pretty much what happened! I have a feeling in the bracket where both screws aren’t catching, we maybe went too far into the brick - can that cause this issue if you drill too far? 

We used a tile drill bit first then switched to a Masonary drill bit, one did come with the screws but we used a better make one we had, both the same size although the one we used looked slightly wider but I don’t think it actually is. 

Also, the screws I got have a little metal bit you put into the raw plug before the screw, guess that’s to reinforce where the plasterboard is? But  I thought the screw had to touch the raw plug to expand it? 

Thanks again ! 

Are the screws spinning, or is both the screws and the plastic plug spinning in the wall? Drilling too far into the brick will not cause any problems if the hole diameter is correct.

The corefix products are excellent and usually extremely strong (I am holding up 2x TV's and 3 very heavy shelves with them), so my first thought was you used a slightly too large drill, but discounted this as exactly the right drill is included.... however you mentioned in your post above that you used your own drill bit which set alarm bells ringing.



The metal core works because the plastic head of a normal rawlplug will pull aganst the outside of the wall when the screw is tightened which will compress the rawlplug causing it to widen inside the hole. 

With a dot-dab wall the head of the rawlplug is sitting against "floating" plasterboard and can pull the soft plasterboard into the air gap collapsing it inwards causing damage to the wall, and/or and preventing the required compression pressure to expand the plug.

The metal collar is there to transfer this compression force from the head to to the harder brick or breeze block beneath to prevent the above. An ingenious idea that works very well (Usually!) 

moneysaver1978

Even with the correct sized drill bit (even the one that came with the screws), it might be that the drill was "jumping" making the hole slightly big. I found that happening in our house on one wall and we think it was just the type of the brick used.

tacpot12

moneysaver1978 said:

Even with the correct sized drill bit (even the one that came with the screws), it might be that the drill was "jumping" making the hole slightly big. I found that happening in our house on one wall and we think it was just the type of the brick used.

This is why I always start drilling with a smaller size drill than the hole I need, and only use the correct size once the pilot hole has been made. You get a much more precise hole doing it that way than starting out with the final size drill. 

lucyplease

Thanks everyone for taking the time to reply, I really appreciate it. 

I’m starting to think now maybe the hole is too big on some of the still jumped about abit as someone said. I’m trying to take the screws out of the bracket where both screws aren’t catching and I can’t get them out as the raw plug is spinning with them so sounds like the hole is too big !

explains why some have caught (if we kept the drill more steady) 

Do you think these would work to correct it ? 

Thanks again!