What to do when you can't get a fixing

[tombrooker84]

Hello Guys,

Recently completed the first fix on a small 2 bed house, as soon as you drilled to get a raw plug in, the brick just crumbled away (thats without using hammer setting and using a slightly smaller drill bit). What do you guys do, I've tried cutting bits of wood, but that is quite time consuming when you have a few to do. I was thinking perhaps quick setting concrete, bonding them in, or perhaps drywall adhesive. Any ideas?

Cheers

Tom

 

[Megavolt]

What are you securing to the wall

 

[Thefailsafe2012]

I assume its back boxes your struggling with. Slap some bonding in there, should go off pretty quick too, and will be nice and solid. Once it's fully dried you could probably drill, plug and screw it if you want as a bit of extra strength, especially for sockets

 

[itselectric]

Set the box in cement and when its hardened drill through and fix.

 

[snowhead]

If it's for boxes, the quickest way is to keep drilling till you find a good spot(s) then drill a new hole(s) in the box to match.

Next best, keep an assortment of pre-cut wedges of wood handy.(various shapes and sizes)

 

[tombrooker84]

Yeh its just back boxes, I cut pieces of wood in the end and used them as raw plugs but it took quite a while, just wondered if it would be worth bonding them instead of drilling them as a matter of course on rewires now, as it seems the areas I work in, I have this problem quite a lot

 

[snowhead]

It's usually sods' that if you get one really good fixing the other will absolutely sh$t..

 

[itselectric]

To be right you should still drill and fix if you're going down the cement route.

 

[telectrix]

stick 'em in with dry wall adhesive, or a good alternative is the one-coat plaster. next day drill and plug.

 

[LlandrilloSpark]

If your using dry wall adhesive or bonding you want to PVA the area first mate

 

[tombrooker84]

cheers for the help guys. Any of you guys used the quick set concrete, I was thinking it might be a bit stronger than bonding and quicker. Also one of the mates I was working with a while ago said soem of the sparks he knows use expanding foam?

 

[kingeri]

I wouldn't use expanding foam, besides being horrible stuff, it won't fix anything reliably for any length of time.

 

[itselectric]

No don't use expanding foam I don't think it likes the pvc insulation on the cable if it comes in contact while setting.
If you use quick setting concrete be prepared to spend a little extra money as it can be dearer plus you'll have to gauge how much you are using as it will probably be set by the time you get to the 3rd box.
The other thing about expanding foam you won't be able to get a decent fixing with th screws when it's set.

 

[imago]

Dry wall/platerboard bonding will do a good job in most circumstances. However, from what you say about your area get some of this Rawl R-KF2 Masonry Resin

 

[telectrix]

surprised nobody's mentioned blu-tac.

 

[Rockingit]

I was starting to sweat that no one had used the words 'grip' and 'fill', either Tel.

 

[steve.b]

blu-tac, Have you seen the price!!!

 

[MarkieSparkie]

If it's just the odd box, Gripfill works provided the substrate is not dusty.

 

[itselectric]

surprised nobody's mentioned blu-tac.

I use all mine fixing consumer unit to the wall

 

[ste mac]

blu-tac, Have you seen the price!!!

Hubba-bubba is cheaper & stickier!

 

[Engineer54]

All they ever used in the past on new builds, was builders cement or bonding. Can't ever remember them going back and fixing them with wall plugs and screws. lol!! Come to think of it, i've never seen one that has fallen out after it's all set hard either!!

Has the builders cement/mortar and bonding compounds become so weak these days then?? lol!!

 

[RyanCheetham]

Wickes do a quick set mortar that sets in about 15mins. Brilliant for this type of problem

 

[Des 56]

There is not so much rendering being done nowadays,but when it was gobbing cement to fix them was perfecto

The standard of alignment and how proud the box was to be,it could be made spot on and much better than drilling and maybe ending up with wonky boxes.especially after the labourer with Gnats brains got the demolition hammers to work on the cutting

 

[ayjay]

what type of brickwork/blockwork is it?
is it newbuild?

 

[tombrooker84]

In this house it is brick, but they have had a damp problem in various parts of the house which has now dried up, but the brick are either brittle and brake to pieces as soon as you touch them with a drill or chisel

 

[odawire]

probably not expanding foam, but there is a sticky foam call insta-stick that will literally stick any two surfaces solidly, they don't even have to be clean its amazing stuff, see it on all building sites now

 

[ayjay]

ah-- the bricks have probably gone all crumbly as they have been damp for years tom
try drilling really deep then use really good rawlplugs
and much longer screws
srart the screws into the plug then tap the head of the screw till the plug goes into the brick much deeper
drill the holes at an angle outwards as well

 

[hubsy]

Have you thought of drilling through the sides of the back box?

 

[grantr37]

there's special resin disks made by SPIT/PASLODE that you can use, drill a hole into the wall, you wet the disk with water then shove your fixing plug in pushing the disk in with it (it is like wet white paper) it has special glue/resin in it and sets fast (2 minutes or so) then it is strong.....the liquid resin seeps into the brick around it and bonds rigid...

they are quite expensive, think it is about £15 for a box of 20......

you will find them on ebay and I think screwfix sells them as well...

 

[grantr37]

OK here's another version I found .......hope this helps....

Product Information | WETNFIX?

quite cheap too......

 

[D Skelton]

Expandy foam!!! Couldn't be without it!

Get the good stuff and you'll have a fixing just as solid as two screws!

 

[Geordie Spark]

Expandy foam!!! Couldn't be without it!

Get the good stuff and you'll have a fixing just as solid as two screws!

Well it is used to fix UPVC window frames - just the foam and NO screws or other mechanical fixings.

 

[D Skelton]

Well it is used to fix UPVC window frames - just the foam and NO screws or other mechanical fixings.

Exactly! I swear by the stuff!

 

[tombrooker84]

will it not corrode the pvc on the cable if it comes into contact with it?

 

[SPARTYKUS]

Still got half a 20kg bag of "fast set" from 7 years ago, its like the best filler ever, once its set its rock hard. The stuff for dot & dabbing.

it appears to be like the salt bag in the ocean, it never empties... Never goes off... For a budget beating solution I'd invest in a bag. And hang onto it for the next 10 years ( think it was probably only a fiver or so, from Kellaways in Stroud)

EDIT when I say never goes off, i mean the stuff in the bagcis as good as the day it was bought 7 years ago. Mixed up it goes off pretty quickly.

 

[D Skelton]

will it not corrode the pvc on the cable if it comes into contact with it?

Not in a million years. There's no property in expandy foam (or at least the one we use) that reacts with PVC.

 

[Guitarist]

will it not corrode the pvc on the cable if it comes into contact with it?

Polystyrene does indeed eat into pvc, but the new expanding foams won't.

If the base of the cutout is very uneven then cement works as a nice "leveller". Gripfill works a treat though, as long as you vac out the dust.

 

[tom79bmth]

I use hardwall and stick back box's in, have you ever try ed to get a back box out when it has been plastered in, never had any probs

 

[onions1066]

Bonding with a bit of cement in, will go off in a matter of mins and you will. Ever shift it, don't put too much cement in though or it will set before you get it out he bucket.