Heat treating screw up...?

[Grizman]

Just did some heat treating to my Yew bow on the belly side of the handle. Took about an hour with a heat gun slowly moving it back and forth on the belly, even used some deflectors as has been suggested here by Del i believe. Looks like some heat leaked around to the sapwood and it shows some light "toasting" or darkening in colour. So how bad of a screw up is this...?
Thanks

[wizardgoat]

I've accidentally toasted some sapwood on a couple bows, and they turned out just fine.
Pics would be helpful though

[sleek]

Sharp corners wil burn like that no matter what you do. Did you round your edges? If not most that will come out when you do if its as you describe.

[Del the cat]

A little discolouration on the edges is ok, you just don't want to toast right across the back which can happen if the hot air hugs the side of the bow and flows round doing some weird aerodynamic thing.
There is always some heat leakage round the side, unless you spend hours jigging it up wit some magic heat resistant putty or glass fibre rope or some such .
Del

[Grizman]

Here is a Pic of the back, a bit of a tan colour for a couple of feet in the centre. I used a few layers of tape on the back too but the heat must have bounced off the caul to some extent and heated the back. I guess it could be cooked linseed oil too...? I soaked it a bit a few days before the BBQ. It seems to want to sand off, not sure what that means. I will get her back on the tillering rack and see what happens...
Cheers

[Del the cat]

Doesn't look too bad to me at all.
I usually have the bow on a narrow caul only as wide as the bow or even slightly narrower so that the haeat can blow by past the bow and down the sides of the caul.
Del