concrete screws wont bite

RobAMerc

folks,

I bought a couple of concrete screws put of battons against my wall.

However they simply will not screw into the wall, and are kinda drilling into it pulling the material out rather than boring into it.

I've used them before no problems, but this time bought new bit (recommended size) to go with the screws and came to this.

Anyone any clues ?
thanks

Radiant Cool Crazy Nightmare

Can you throw up a pic of what you are using?

the_pen_turner

what type concrete screw
what length
what wall material
what bit size
what are you drilling it with, sds, or percussion
what are you driving it with

BrokenArrows

Are you using an electric screwdriver? Do you have it on reverse?

dodzy

BrokenArrows wrote: »

Are you using an electric screwdriver? Do you have it on reverse?

I guess the OP is actually trying to drill the screw directly into the concrete without drilling the pilot hole first. PICS would solve it quickly.

Armchair Andy

dodzy wrote:

I guess the OP is actually trying to drill the screw directly into the concrete without drilling the pilot hole first. PICS would solve it quickly.

My guess is the drill bit is too big. Could be old concrete either.

RobAMerc

the_pen_turner wrote: »

what type concrete screw
what length
what wall material
what bit size
what are you drilling it with, sds, or percussion
what are you driving it with

self tapping concrete screw
100mm
concrete block
6mm bit - as per that advised by the box
percussion drill
electric screwdriver with correct torx bit
I think they are WUrth screws- could be wrong though.

BrokenArrows wrote: »

Are you using an electric screwdriver? Do you have it on reverse?

is this after hours ?

dodzy wrote: »

I guess the OP is actually trying to drill the screw directly into the concrete without drilling the pilot hole first. PICS would solve it quickly.

see above

Armchair Andy wrote: »

My guess is the drill bit is too big. Could be old concrete either.

Bit is the size prescribed by the screw manufacturer - have used them before but to much more success !
Also, if it was too big, would it not just drive in and pull out really easy ?

hatchman

Make sure that the hole in the baton is slightly bigger so the screw can spin freely in it.

SuperTortoise

Blocks are less dense than poured concrete so you need a special fixing to grab it.

bbbaldy

SuperTortoise wrote:

Blocks are less dense than poured concrete so you need a special fixing to grab it.

I have used concrete screws into block with no issues. Worked really well.

fred funk }{

hatchman wrote: »

Make sure that the hole in the baton is slightly bigger so the screw can spin freely in it.

This.

RobAMerc

ok, I see what you are saying about the hole in the baton but its not the issue.

After the screws refused to bite, I tried driving them directly into the holes without the baton.

They are just sitting there spinning, throwing dust out like I was just drilling the original pilot hole with a masonry bit. they will not bite and self tap !

fred funk }{

Sounds like the wrong sized bit then. Try a smaller one.

red sean

RobAMerc wrote: »

ok, I see what you are saying about the hole in the baton but its not the issue.

After the screws refused to bite, I tried driving them directly into the holes without the baton.

They are just sitting there spinning, throwing dust out like I was just drilling the original pilot hole with a masonry bit. they will not bite and self tap !

If you have (or can get your hands on) a vernier caliper measure the internal diameter between the threads and drill the hole the same size. I had a similar problem with a box of them years ago. The recommended drill size was 1mm too small.

dodzy

RobAMerc wrote: »

self tapping concrete screw
100mm
concrete block
6mm bit - as per that advised by the box
percussion drill
electric screwdriver with correct torx bit
I think they are WUrth screws- could be wrong though.

is this after hours ?

see above


Bit is the size prescribed by the screw manufacturer - have used them before but to much more success !
Also, if it was too big, would it not just drive in and pull out really easy ?

Op, you obviously know what you're doing. But in this case, I'd be inclined to up the big size to 6.5mm. Failing that, move up to 7mm. Still no joy, then plug the wall or use rawlbolts if circumstances allow

alta stare

Have you tried thunderbolts? Iv used them to fix comms cabinets to walls with zero issues. They give a good tight fix.

http://www.unifix.co.uk/thunderbolt

ballystephen

6.5mm drill for them

Sleeper12

If you are putting up batons why not just drill & plug. While concrete screws do work I've never found them as good as wall plugs