Updatey Update Post

JT came round and he did a good deal of work on the bow under my watchful eye. There was the usual panic as the spoke shave or plane dug in and started to tear, but careful use and resorting to the rasp kept things under control.
The bow progressed nicely to about 100# at 20" at a modest brace which is pretty much the amount of work I'd hoped for.
The oddest occurrence was the magic aluminium string adjusting ring breaking whilst try to brace it for the first time! I wouldn't have believed it, had I not witnessed it myself.
Update:- I got an E-mail from my mate Mick the Blacksmith, he said :-

The break is a typical stress fracture and probably started from a small crack sometime ago.
In industry when they test the tensile strength of something by pulling it apart, the fracture is the same as you have on your string thingy.

We took some good video at three stages of the progress.
https://www.youtube.com/watch?v=dvSI_onb42o

Previous day my mate Rob came over with some stuff to do. He had a half log of Wych Elm which we ran through the bandsaw laid out as a primitive. The stave has a huge amount of reflex so I though a wide flat design would have less stress than a longbow. He also had a warbow that had over 4" of set... it was pretty obvious why... the bow was over 1mm thinner at the arrow pass than it was for about a foot either side of it! It was obvious to see and to feel, dunno how someone can make a bow like that (he'd paid good money for it). He felt it was no good, so it was worth risking drastic action.
We got the bow strapped down mid limb on one limb (back down). We'd protected the back with multiple layers of masking tape and lightly clamped side cheeks to the bow to keep the heat on the belly. About 5 mins with the hot air gun and we pulled the bow down straight, strapped it down and heat treated the belly over the thin area. After lunch, we had a look and found a series of short transverse cracks had opened up. I recon these were fine chrysals that weren't obvious before, but opened up as the bow was heated and straightened. What to do? Well we rasped out that area of the belly and glued on a patch of heat treat Yew which will allow the bow to be re-tillered with the grip at the correct thickness. Rob left with patch all strapped up (it takes overnight for the glue to cure).
While he was over here we glued some horn tip overlays onto a Yew kids bow he's made for his son.
Heard back from Rob, he's re-shaped the belly where the patch is, and done a bit of scraping here and there to take off some thick areas. The set is now just 3/4" and the draw weight is up from 112# to about 150# ! The tiller looks much better now. Result!