Can anyone recommend a wheel builder in around Oxfordshire/Berkshire

Cheers

My recommendation is to get the bits, download a guide (here) and DIY. It's really pretty easy and it'll save a fortune plus means you can fix your wheels out on the trails…

And even if you've got no mechanical aptitude, the worst that could happen is that you take it all apart again and take the bits to a shop to do it for you.

OK, here's the problem…I'll try and keep this brief
Merlin wheel build got spokes mangled by chain thrown over top sprocket
I've sorted this by taking greater care with limit screw on the mech
Mangled spokes replaced – and wheel trued easy/peasey

Every now and again I'm getting spokes snap and not just the replaced one's – this has gone on over the months
spoke snaps – replace, true wheel and tension – ad infenitum

I'm thinking I'm over tensioning the spokes – but without the experience or a fancy gauge I'm guessing (?)….Thought is now to get a complete rebuild by someone who know's what they're doing

The guys at Broadribs in Bicester can build pretty good wheels.

More likely that it is under-tensioned, meaning the spokes fatigue and snap.

As Sam suggested, breaking spokes are usually caused by loose ones – once you've ridden them loose you'll likely have them break sooner rather than later.

Solution. Dump all the spokes, get new ones and rebuild.