thanks Andy,
all makes sense. I actually did some calculations and I think I've
worked out that there's not as much force on the bolts as I originally
though. My original panic was that worst case, let's say there's the
full weight of the arm (30Kg) plus the weight of the plasma (34Kg)
hanging 26" from the wall...there could be a lot of leverage pulling on
the bolt/s.

In fact (if my GCSE physics serves me), it's entirely dependant on the
distance the top bolt/s is from the pivot point...i.e if the top bolt
were 26" up the wall, the force pulling the bolt out would be equal to
the weight of the stuff dangling at the end of the arm...now 63Kg
doesn't sound so bad.

Looking at the mount, it'll be trying to pivot around the bottom set of
bolts. The top set of bolts will be about 21 inches above the bottom.
So the ratio of the arm length to the distance between the pivot point
and the bolt is 1.3:1 i.e there's 1.3 times more weight pulling the top
bolts out, than the weight of the stuff dangling. ie. worst case
(assuming the boy doesn't use it as a swing), is about 82Kg.

So ignoring sheer (no doubt that'll be my downfall...along with
boy+swing), if I have 7 bolts along the top, 12Kg per bolt trying to
pull out of the wall at 90 degrees. If I add the boy to the equation
and assume he's static (let's say up to 36 kilos, that gives me about
5 years growth to train him not to swing on it), the total force
pulling on each bolt is say 99Kg * 1.3 / 7 = 18Kg. 25% margin of error
gives 23Kg per bolt.

The fischer FIS V resin with an M8 * 110 A4 stud looks like it takes
6KN Tensile and Sheer or am I reading the specs totally wrong ? that's
about 600Kg per bolt isn't it ?!!

Ant.