Thanks for the feedback.
I'm surprised by the red oak: it's given me a much heavier bow than others indicated was likely.
It's about 1 1/2" wide at the hand, so probably a bit too wide. It's only taken about 2" of set though, which seems ok. I'll have a play with some different profiles and tillering sequences next, and try and get something a bit lighter as I trundle along on my learning curve.
Nice bow.....and I really like the design of your tillering stick. Mind sharing a few detail shots of it?
It's really a very simple affair: an offcut of 19mmx85mm spotted gum (the other 2ish metres has a particularly straight grain for something else later!), with holes drilled every inch, and a couple of holes at the top, into which are slotted some bolts; the top ones that the bow sits on have nuts to hold them in firmly; the lower ones just get pushed into the hole to hook the string over and hold at whatever draw length I'm up to (or pull the string down with the spring balance to measure weight). I just hold it in the vice I have mounted on my tailgate for sharpening chainsaws etc (it's actually proven a handy workbench set like that), and a plumb line soon gets me fairly straight.
I'll possibly build another though, a bit taller, with eye bolts and pulleys; I'll want some mechanical advantage, and won't want a tillering board to fail if and when I'm exerting 100+ lbs on a stave, as is the ambition...!