Saturday, 10 November 2012

Caramel and Cream & Reversing on the Tiller

Brian's bow is now getting smooth and supple, it's back to 50# at 30" now, I've been straightening up the edges, slimming the tips and taking a tad off the last 1/3 which is now beginning to bend nicely. At one point I thought I'd over done it and made the lower limb whip ended, but a few strokes of a medium rasp at mid limb and a bit off the upper limb had it back to looking great and had given me another inch of draw length. Teasing back these last few inches can be tricky when striving for the perfect curve. It's easy to take too much off at the tips as a few strokes of the rasp is insignificant at the fat end of the limb, it is rather a lot when you are down to less than 15mm thick at the tip.
I've been going over the limbs with a cabinet scraper and 120 grit wet & dry paper removing all the tool marks and it's looking rather pretty.
I couldn't resist giving it a first wipe over with Danish Oil, wow, the colour of the grain shone out and the heart/sap wood suddenly looked like caramel and cream. You can see the difference from the previous post, of course, this isn't the fianal finish, it's just a first wipe to show up any marks I've missed.
Spot the slpice in the lower left pic, you can also see the reddish blush from the remains of a knot.
I'm making up some full length arrows so I can shoot it at the club tomorrow. It's already had about a dozen or so of my 28" arrows and shoots fast and true even with my tillering string with it's metal toggle in place!
Must press on and make a string too.
Once it's had a few more arrows through it I'll make any final adjustments and think about horn nocks, grip and arrow plate.
I've made a string and checked the draw weight and length, it's about 50# @31" difficult to read it accurately .
It was looking a bit whip ended on the lower limb so I carefully checked the bow was supported at the centre and the string was being drawn one inch above that (in line with the arrow pass). I reversed the bow and took and it looked much better. The pictures illustrate the surprising amount of difference and I've added ellipses in 'paint' to help show it up. I shall probably keep the upper and lower limbs as they are in the better view, it would seem daft to insist on trying to adjust the tiller to conform to my previous arbitary choice of upper and lower limb.
Maybe I've just got 'tillering fatigue' but the pic on the right looks much better to me. I'd welcome any comments on this.
Explain More:-
Effectively all that is changing in the two pics is the point on the string where it is being drawn, which is about 2" different in the two pics. This is enough to make the bow bend slightly differently. This is why the technique called string walking is a nasty thing to do on a self wood bow.
As an example of string walking:-
At very short range you could maintain your usual anchor point but draw the string from a point 2 or 3" below where the arrow is nocked, thus that the back of the arrow is aligned with your eye, and yet you have your usual anchor... great for easy aiming, not so good for the health of the bow if its made of wood.

1 comment:

  1. Good information Del, thanks for sharing.

    ReplyDelete