Thanks for the responses BHT and Twisted.....
It's not what I would call 'my design', but more
an amalgamation of ideas that I had seen.
Like most jigs, mine was going to be the most elegant,
attractive and accurate of all jigs !!!! Sadly, although
it works extremely well, I must admit that it's a bit
of a bodge.... well it's a lot of a bodge!!! I started
to lose the fight for elegance when I tried so hard and
failed miserably, to drill a hole in the calipers.
Trying to secure this strangely shaped item caused
me a huge amount of time, and by the time I had it
down, I was fairly cheesed off with the whole thing.
So, big tip here for anyone thinking of attaching
calipers to anything,find a way to get a hole in it...it'll
save so much time and energy.
BTW, just while I'm on here.....what would be the
correct way to drill the hole, the caliper says it
is hardened......advice please, thanks
Thanks again for the replies chaps
Best wishes - Jim