anchor bolts, what size masonary drill bit?

Muckit

Lads

Does anyone know what size masonary drill bits I would need to use to fit M6 and M8 faithfull shield anchor bolts (rawl bolts) in a wall?

I tried using a 10mm for the M6's but they seemed tight in hole and didn't want to belt it in in case it got stuck halfway and couldn't get it out!

Am I using them right? Wouldn't be used to working with them

Any help/suggestions appreciated

snowman707

M6 12mm
M8 14mm
M10 16mm
M12 20mm
M16 30mm

Muckit

Thanks Snowman

I then proceeded to drill a 12mm hole and thought the M6 looked lost in it. When I tightened it up, there was still a bit of play....:o

I packed up kit and said I'd look at it at the weekend when I'm a little cooler:mad: (Hate when you've planned to get a job done and it doesn't go to plan!)

Your a man who seems to know his stuff, so i'I have another go at it. Thanks a mil for info;)

cjpm

We normally drill them so they are tight, so 10mm as you did for that size bolt. Spin the drill in the hole for a few extra seconds to make it a tiny bit bigger. Make sure the hole is deep enough!!!!

Run the nut out to the end of the bolt (or use a spare nut) and drive it home with the hammer. There should be no need to belt the **** out it as if you do you'll destroy the threads.

If you bore the hole too big you'll be ages tightening them and they won't be quite as secure.

Also if you could you could run the bolt through what ever you are bolting onto the wall and then drive the bolt in. Saves opening the nut again and in the case where there is more that bolt on the item, there is no chance of the bolts and holes not lining up correctly.

kay 9

You could also use hilti anchors;) Serious job also, just that you have to cut threaded bar to length.

Melodeon

The drill size required is usually stamped somewhere on the fitting, usually on the ferrule that holds the expanding leaves in place, the piece just below the washer in your picture.

As already said, make sure to drill the hole deep enough, clear all the debris out of it, and run the nut and washer down to the ferrule to keep everything in place when inserting it. It MAY require some persuasion with a hammer, but nothing much beyond a few GENTLE taps.

JohnBoy

also masonry bits can wear out too. had it happen recently using some hammer in fixings, no matter what I did they wouldnt go in, turned out the wings on the bit had worn from using them in the walls of our house which contain some awful lumps of hard sandstone.

what happen

been their done that. i find the threaded bar the best straight true the wall live you out.anchor bolts o good in bad block walls. not last as long as threaded bar anyway

Muckit

Got the job done anyways this evening, thanks for help lads

Used fitting more like these though, with the expander bit at the end , rather than half way up it.






Found when I was tippin them in with the hammer the first type were inclined to expand:rolleyes: No probs with second type

Used a 14mm drill bit for the M8s

irishh_bob

Muckit wrote: »

Lads

Does anyone know what size masonary drill bits I would need to use to fit M6 and M8 faithfull shield anchor bolts (rawl bolts) in a wall?

I tried using a 10mm for the M6's but they seemed tight in hole and didn't want to belt it in in case it got stuck halfway and couldn't get it out!

Am I using them right? Wouldn't be used to working with them

Any help/suggestions appreciated

those ones leave almost no room for error in that if you dont drill deep enough or drill too deep , job is not done properly

better are the one which have a bolt head , you drill the hole , tap in the entire bolt and then unscrew out the bolt while the sleeve ( or whatever its called ) remains , you then rescrew the bolt over the gate hanger or whatever it is you intend to mount - hang