Drilling near a filled in hole

[mbu11]

I have mistakenly drilled holes in the wrong place when trying to put up a shelf. I marked the holes in the correct place but the holes ended up being lower than intended.

I filled in the holes with Polyfilla but now when I try to drill the holes in the correct places the drill just tends towards the previously filled holes since it is so near and offers less resistance.

Does anybody have any advice on how I can drill the holes in the correct place without it re-drilling the old holes?

 

[mattylad]

Drill trough a piece of something else that is more solid.

I.E. a block of wood securely held against the wall (or even held by a small tack).

This will prevent the drill bit wandering.

You can have the hole pre drilled in the wood.

What is the wall made from and how are you going to ensure the screw stays put?

Polyfilla is pants.

 

[opps]

Polyfilla is indeed paints. Two pack filler (car filler) would be better.

Alternatively start with a much thinner drill bit, keep going through into the brick, then use a wider diameter bit.

The downside is that you will need to use longer screws and plugs.

An SDS drill, rather than a hammer drill will help you to drill truer holes.

In the past when I have had to re-drill for curtains poles, etc, that have fallen down, making effing big holes as they fell, I hve drilled deeper into the bricks pushed a plug all the way through the plaster and into the brick. I have then put the screw in, without any fittings and squirted in an anchor fitting epoxy ( eg http://www.twistfix.co.uk/products/resin-injection-systems/epoxy-resin-injection-system-product.html ). If I haven't got any anchor fix I use "car filer". Once hard, I remove the screw sand back the filler and rehang the curtain.

I know that your case is slightly different but you would be able to angle the drill until you hit the brick in the right place and then pull the drill around so that you are now drilling straght.

You can then use the filler technique. This will have the advantge of enabling you to strighten up the screw even if your plugs are sliglty wonky. The filler will harden in minutes. once it has started to set remove the screw and hang your shelves.

Be warned that the epoxy anchor fillers set extremely hard and are a mare to sand back. They can be costly and the stuff in the nostle sets quickly, maeaning that you have to do all the fittings in one hit, any left over will need to be binned. "car filler", styrene resin filler is easier to sand back, cheaper but less strong, in this case however it is the brick doing the load bearing.

 

[JohnD]

If you have a loose hole, this trick is easier and cheaper than injecting resin, and fine for domestic work, unless perhaps you are hanging a heavy boiler on the wall.

- make sure it is deep enough and wide enough for the plug and screw to go right in. You need at least 30mm of brick or block, plaster has no strength. Screws supplied with curtain-track are usually too short. If you have a big wide crater, drill deeper into the brick and use a longer plug and screw. If you really have a huge crater, sand and cement mortar (damp the hole first) will fill it better, and you can drill again once it has set. There will often be an air-gap behind, so use this trick anyway.

- clean out all dust with a vac or a water squirt

- insert the nozzle of a no-more-nails tube, or any own-brand equivalent at a tenth the price, and fill it from the back, withdrawing as you squeeze, so there is no air bubble at the back

- press your plasplugs into it, in exactly the right place, and recessed slightly below the surface. You can put a screw a couple of turns into the plug to use as a handle.

Smooth the surface with a wet finger, remove any excess, leave the adhesive overnight to dry. The next day you can drive your screw firmly into the plug and it will not rotate or come loose in the hole

 

[Filo]

If you have a loose hole, this trick is easier and cheaper than injecting resin, and fine for domestic work, unless perhaps you are hanging a heavy boiler on the wall.

- make sure it is deep enough and wide enough for the plug and screw to go right in. You need at least 30mm of brick or block, plaster has no strength. Screws supplied with curtain-track are usually too short. If you have a big wide crater, drill deeper into the brick and use a longer plug and screw. If you really have a huge crater, sand and cement mortar (damp the hole first) will fill it better, and you can drill again once it has set. There will often be an air-gap behind, so use this trick anyway.

- clean out all dust with a vac or a water squirt

- insert the nozzle of a no-more-nails tube, or any own-brand equivalent at a tenth the price, and fill it from the back, withdrawing as you squeeze, so there is no air bubble at the back

- press your plasplugs into it, in exactly the right place, and recessed slightly below the surface. You can put a screw a couple of turns into the plug to use as a handle.

Smooth the surface with a wet finger, remove any excess, leave the adhesive overnight to dry. The next day you can drive your screw firmly into the plug and it will not rotate or come loose in the hole

Or you could just use some of these

http://www.screwfix.com/p/fischer-wet-n-fix-pack-of-50/77888



They work a treat and give a good solid hold

 

[JohnD]

Sat Nov 17, 2012 11:27 am

cor, that was quick.