I haven't done much scraping on account of a banged up knee, so here's the currently off-balance tiller. You can see, especially in the drawn shot, that the upper limb is stiffer than the lower, which is the opposite of what I want.
I don't usually pull at a bow if I see something wrong with it to avoid set, but this can be a sacrificial lamb.
For this careful, slow tillering I would usually clamp my bow to a bench and just scrape at the belly according to how I mark the wood, but my clamps are with a friend.
I hold the bow in one end with the tip on something that won't damage the wood, like softer wood, and use the other hand to hold and move the edge of the machete up and down the length of the limb, varying pressure depending on where I've marked the bow for more removal in stiff areas. Having the concave and convex edges on my machete allows me to remove wood in pinpoint or broad areas, and lets me shape the belly faster.
Sometimes, though, a scraper jumps. It happens less with my draw knife than it has with my machete, but it's easy enough to fix.
The easy side of my rasp goes over the lumpy patch very gently and no more than necessary to level the wood.
After the rasping I scrape the area before checking anything. A clean surface allows me to check for chrysals, which are very common in black locust.
I hadn't done much adjusting in this shot, but there's a little bit of difference. This mostly shows how slow and methodical tillering is supposed to be as this represents half an hour of work.
Now I'm going to have to accept that this bow, with this much mass, at this length, with these flaws, at these dimensions, is going to take some set.
This limb has a relatively uniform taper and no real trouble from knots. It will take set, but very evenly.
This limb comes out of a knot and is more narrow out of the knot than the rest of the limb, telling me it's going to take set in the inner limb. It's pretty reliable that the part of the bow that takes equal weight on less cells is going to take more set.
This is that knot. I knew it'd be trouble eventually because I had to get it bending. At least it'll be pretty!
A couple hours later (which I should have photographed) I have some pretty major differences. The upper limb is obviously still slightly stiff, but the bend is uniform enough to avoid chrysals and draw fully. I'm at fifty one pounds at twenty five inches, almost my draw length and pretty much what I was aiming for,.
And as you can see set looks about how I predicted.
Total set pre-heat treating is about an inch. That's actually less than I was allowing for; I expected two inches of set at this point. I'm going to give it a light sanding and toast the belly again, hopefully removing some set.