How to tighten bolt?

[SmoothCriminal]

I have an lcd wall mount that takes a big screw on one end and a bolt on the other.
I try to tighten the bolt as much as possible so that the monitor is held upright. However, when I turn the wrench I can see the screw head moving on the other end. How can I tighten the bolt as far as it can go?

 

[Burnerman]

Doesn't the screw head have an allen screw socket or similar?
If it doesn't, maybe you could hold the head with mole grips, or replace the screw with a bolt so you can hold both ends.
John

 

[SmoothCriminal]

Doesn't the screw head have an allen screw socket or similar?
If it doesn't, maybe you could hold the head with mole grips, or replace the screw with a bolt so you can hold both ends.
John

It doesn't have a socket, so holding it in place is difficult.
Will mole grips hold such a thin head?

 

[JohnD]

, please indicate which of the screws you are talking about.

 

[SmoothCriminal]

It looks to me like a stud, where the other end is meant to be firmly fixed into the wall. I deduce it isn't. Does it go into brickwork, wood or plasterboard?

It goes into brickwork. The bolt and screw I'm having trouble with are the horizontal ones.

 

[JohnD]

Take it out and photograph it from several angles.

Have you tried putting it in from the other side?


(They're all horizontal). Which one?

 

[SmoothCriminal]

Take it out and photograph it from several angles.

Have you tried putting it in from the other side?


(They're all horizontal). Which one?

These are the ones:

 

[JohnD]

Let's see the underside of the head.

 

[SmoothCriminal]

Let's see the underside of the head.

Hope this is clear enough

 

[Burnerman]

It looks like it may have been splined at one time and the splines have worn.
Replace it with a hexagon bolt and nut.
John

 

[SmoothCriminal]

It looks like it may have been splined at one time and the splines have worn.
Replace it with a hexagon bolt and nut.
John

Thanks for that- I just realised I have another problem in that I cannot unscrew it.

Will a pair of mole grips help?

 

[JohnD]

I wonder if it might be square under the head, a coach bolt.
Photo is not detailed enough.


Is the hole in the fitting, at either end, square or splined?

 

[Burnerman]

I think there's just enough head showing for some grips to hold......the joys of the Nyloc nut!
You may get more purchase by pushing the head in, too.....there may be just enough spline or whatever left for it to hold.
John

 

[SmoothCriminal]

I think there's just enough head showing for some grips to hold......the joys of the Nyloc nut!
You may get more purchase by pushing the head in, too.....there may be just enough spline or whatever left for it to hold.
John

Would an adjustable wrench work better?

 

[JohnD]

yes

or a spanner that fits, even better