Monday, 22 September 2014

Teasing it Back

The bow is back to 100# at 28" now, having rasped off an even amount along the belly and taken out the rasp marks with a scraper.
I'm aiming for 100# at 32" but want to allow for the bow setting down so I'm not taking much more off.
The next 4" of draw would give about 16-20# extra draw weight so it's nearly there. It's ready for horn nocks and slimming the tips right down, that will bring the draw length back a bit more. I'll probably stop removing wood when I get to 100# at 30" and just pull the last 2" allowing it to be slightly over weight.

The bow has that nice medieval shape, much stouter than a Victorian longbow, tapering at the tip more like the wing of a Spitfire than a skinny straight taper.
The back is pristine over most of it's length with the under bark layer showing as dark streaks. Only at the tips have I reduced the sapwood a bit. There is some twist and undulations in the stave  which make the grip appear slightly angled, but over all it pulls straight and true. It has a little natural deflex, which is quite handy as it makes bracing a little easier. I need a stringer to brace it, but I can get the string off ok (well, I have to tense my belly pretty hard and heave.)

Here it is with the horn nocks done and the tips slimmed, it's still 100# at 28". You can see it's bending pretty hard. To me the left (lower limb) looks to have a slightly nicer full bellied curve. I'll take little off all over and a bit extra mid limb on the right (upper limb) It shouldn't need much. A light rasping and then scraping out the tool marks should do it. At this stage I like to have the back really clean and keep checking over the bow with my fingers feeling for any thick or thin spots or irregularities, slowly getting it closer and closer to the final finish.
I've just done a little more and filmed it in slo-mo as I briefly pulled it to 30".
The slo-mo was used in case it exploded! (Well you can't accuse me of being over confident!)
I've just noticed the pale area on the belly half way along the left limb... it's a bit of masking tape I'd stuck on there to act as a dam while I put some low viscosity super glue on a tiny filled knot. It makes it look a bit weird as it draws the eye to that area and makes it look weak.

Update:- I've had some test shots.
I can't draw it 32" but I weighed it on the tiller at 28" and it's about 84# which I should be able to pull.
I warmed up on my faithful old 70# Yew longbow and then had some shots at 28", Bit of a struggle but it bangs 'em out. I then went to my mock Tudor arrows (32" long) as they are a bit heavier and better suited, not sure how far I drew, but at least it gave it some exercise. It sit's slightly oddly in the hand as there is dip in the sapwood and some localised twist there. If you just looked at that point you'd think the bow was twisted, but when you look down the entire length, it makes sense.
I didn't shoot too many as I could feel it on my shoulders, I also didn't try to go mad and get the full 32" draw.

Out of interest, I did the arithmetic and 84# at 28" does tie in nicely with 100# at 32"

No comments:

Post a Comment