Be gentle with me guys as this is a lot of firsts and highly experimental with a few erroneous assumptions thrown in.
I decided to try a Hazel flight bow modelled roughly on a nice Hazel bow I'd made ages ago.
Mistake 1. I thought the Hazel bow was 35# when it was 30# at 28".
Mistake 2. I thought it was vaguely symmetrical, but it turns out the lower limb is a couple of inches longer! (but it shoots like a dream)
The game plan was to draw the limb shape of the straight Hazel bow at FD, brace and unbraced and the make the flight bow with that FD curve as reflex at unbraced, and straight limbed at FD
Well we all know how plans turn out
The limbs were made individually from rapid seasoned (read "impatient old git") Hazel and first mounted in a rough try out riser block. I then drew up a better riser and made it up from some Mahogany planking. I like the way the limbs sort of splice into the riser. I used the trick from PA (Pearlie's trick?) of pegging with a wooden skewer to hold 'em in alignment while glueing/binding/clamping.
The limbs have untouched backs. Yes I did my pet trick of leaving the bark on so I could scare my self witless when it went CRACK and popped off
Most of the recurve pulled out despite some heat treating, so there is little stored energy at brace. However I must have got some geometry about right as the tip deflection is similar to the first bow... well I s'pose it's bound to be innit? It's a bow... (slaps furry head with paw).
I ended up with 35# at 27" which is pretty much what I was after, mind I need to check on how we measure such things when it has an arrow shelf.
Anyhow the chrono' would be the judge.
First two shots were a bit tentative and I'd built up the nocking point a bit tight...
151 fps
152.4 fps ok but no cigar.
The whipping round the nocking point came off giving a looser fit, and I let loose with a slash/flash draw.... Wow!
172.2fps better check it's not a miss-read
164.6
164.5
What I really noticed is how much cleaner and consistent the readings were compared to a longbow where the arrow does the snake dance as it leaves the bow
I haven't got a decent 'in the hand' FD pic yet, I'll post one if I get one later.
Seems like a pretty respectable speed for a bit of Hazel... ?
All comments, comparisons, suggestions and witticisms welcomed.
Oh yes the arrows were about 350gn
I could claim the fancy layer of Elm between the Hazel and the horn at the nocks is an artistic flourish or a cunning interface layer for superior glueing... but it's really cos, by the time I'd narrowed the tips with their temporary Elm nocks, the string a whisker too long
. So by not rasping off the entire temporary nock I could gain about 1/4" at each end.
Del
Video of the nearly finished bow flexing on the tiller, here:-
http://bowyersdiary.blogspot.co.uk/2015/02/hazel-flight-bow-nearly-there.html
