Advice on how to best drill accurate holes into interior wimpey no-fines walls?

i cant work out what  you are drilling into, the walls are hollow are they? what do you mean no- fines?

 

http://en.wikipedia.org/wiki/Wimpey_no-fines_house

 

blimmey, so they are cement walls with stones in the mix, hmm

 

just a really course mix, generally no sand, so plenty of voids - and the aim was to allow the finished walling to remain aerated, seemed a good idea at the time

how about a couple of inches thick of timber held up flush with the wall, that you can use as a template/guide that'll stop the wandering

or a much smaller pilot to get you started

 

I had to try to drill a hole for a waste pipe in a kitchen through a no-fines wall. Ended up chiselling a hole then filling it after the pipe had been put in position. There's really no easy way to drill holes into these damn walls though.

 

Like Sean says the smallest possible pilot drill and work up in sizes.
One possible way worth trying might be, as I assume there is some plaster, to cut a peice of thick ply with the correct size hole and some nails knocked through so they just give spikes on the back that can grip the wall when pushed against it.

teabreak

 

You will know that with SDS drills you just hold the drill and it does all the work easily!

Don't let it. Remember the old percussion drills, how hard you had to push to even go into brick?

Push like that, as hard as you can, straight in.

Mr. HandyAndy - Really

 

Hi Stevy G

I would use a diamond tipped 6 or 7mm "core drill"

http://www.screwfix.com/p/diamond-core-drill-18-x-85mm/93712

The one shown here is 18mm but you can get 6 or 7mm from any tiling centre or good store.

Keep the drill speed low but pressure high and keep the bit wet to stop it overheating, if it overheats the surface clogs and blunts real quick.

The desing of the diamond tip allows you better control over the route the tip tries to take. Dont forget that the stones found in concrete are as hard as porcelain and most masonary or TCT tile cutting bits will not penetrate them thats why the bit wanders so badly, it just slides off the stone.

However, when you first encounter the stone just use light pressure and allow the abrasive action of the  bit to do its job, once you have started to penetrate the stone then apply the pressure.

Have fun, each hole will take upwards of 15 or 20 mins to cut

Hope this helps

Russ

www.iiplumbing-services-derby.co.uk