[Goof]

My DIY adventures always seem to end in disaster...after a horrific time with ceiling mounting my Pj screens (into a roof seemingly composed of talcom powder), my powdery walls are now taking a pounding for my 32" LCD's mounting.

My bracket has 2 mounting plates - measured everything up and drilled holes for first set. The top 2 bolts go in fine but when doing the bolt for the lower half it started pulling the rawl plug out of the wall and now I've got a bulge
(forgot to mention, it's on a chimney flume).

I figured the top 2 would hold though so went to drill the holes for the 2nd set/other half of the bracket - first drill hole and it hits a hard patch and skews the drill off the the right. So now I've also got a hole that's too big (and probably squint).

Can anyone tell me why the rawl on the first half has tried to pull itself out? And also whether there's anything I can do about this 2nd oversized hole?

[stevelup]

Hi

I'd move the whole thing a few inches down or up and try again.

A few bits of advice:-

1) Drill a pilot hole with a small drill bit first (5-6 mm is a good size). This will stop the drill bit skewing off as you described.

2) Make sure you are using exactly the correct size drill bit for your rawl bolts. If you are using M10 bolts, you need a 16mm drill. If you are using M8 Bolts, you need a 12mm drill. The rawl bolts should be a snug fit in the hole. Make sure you keep the drill exactly level and don't wiggle it about as this will make the hole too big.

3) Finally - and most important - you must absolutely resist the temptation to overtighten the rawl bolts.

If possible see if you can borrow an SDS drill and the relevant bits - these produce much cleaner holes and are a lot easier to use.

Do you *really* need to use rawl bolts anyway? They have a tendency to destroy whatever structure you are fixing into - especially if overtightened.

My 42" plasma - which is a good deal heavier than a 32" LCD - is fixed to the wall using six M8 coach screws with suitable wall plugs.


Steve

[Goof]

Thanks Steve, that's very helpful advice .

I was using drill bits that were approximately the same width as the rawl plugs - just held them head to head. And I didn't actually realise that lower bolt was being pulled out until it was too late

A bit loathed to start again and make another 6 holes in the wall though!

[stevelup]

There is a workaround if you really don't want to start again.

But before I make that suggestion, I'd make the following statement - you really don't need six rawl bolts to hold a 32" LCD. As long as your upper ones are sound, it will be fine - just leave the lower ones loosely inserted.

If you're not comfortable with that (although I'm confident it will be fine!), you could try the following:-

Get hold of some "gripfill" - it's in a green tube if you want stinky solvent based stuff and a yellow tube for the stink free / solvent free stuff. Don't use anything other than genuine "gripfill". It's available from builders merchants / Screwfix. TLC (the electrical wholesaler) keep the stinky green stuff.

1) Carefully remove your errant rawlbolt shield(s) and fill the holes with gripfill. To get the rawlbolt shields out, you will probably need to push the bolts back in as far as they will go before gently wiggling them out.

2) Put the rawlbolt sheilds back in and clean the excess gripfill off.

3) Immediately fix your bracket to the wall. If you wait any amount of time, the gripfill will set an you won't be able to screw your bolts in(!)

Disadvantage to this method? You will never get your gripfilled bolts back out without destroying that bit of wall.

Personally - as long as your upper two bolts are absolutely solid, I'd forget about it and just go ahead and mount your display - the bottom ones don't really do a great deal. All the "pull out" force is on the top two.


Steve

[Goof]

Thanks again Steve - yes, I wasn't to worried about that lower one but first the hole I made for the 2nd bracket (the hole that's too big) is one of the top ones. That said though I've just realised there is 4 fixings on the bracket so I should be able to just try a new hole.