Saturday, 9 July 2016

Flight Bow Tricky Tillering

The flight bow has come on deceptively fast, it almost looks like it's simply been cut out by numbers to a pattern, but the actual tillering is V tricky.
The bow is so short and the actual working limbs so short that slight errors in how the bow and it's string are supported on the tiller make a big difference. I've shaped the grip, reduced the levers and made a shoot through arrow pass/rest. It's been braced and the arrow/finger position marked with tape to allow it to be pulled accurately on the tiller.
The shoot through hole may well need enlarging considerably, but better to start small and make it bigger... it's hard to reduce the size of a hole! Bear in mind flight arrow fletchings are very minimalist too.
In the pic, Emily Kitten is checking that the grip is a good tail fit... very important the tail fit!

 Where the lower limb had looked stiff and I'd eased it off, it now looked weak. I've been checking an actual draw by looking at my reflection in the patio doors. I finally got it looking pretty even and plucked up courage to draw it to 24", it's actually only 50# and gave a slight noise at one point, not quite the dreaded death 'tic' but a bit worrying.
You can see from the pics it's taken a slight even set, that's fine. I'll strap the limbs back flat and heat treat the belly. I was tempted to add a hint of deflex/reflex, but the old adage of keep it simple is probably sensible.
It's looking a bit more elegant now, but doesn't have the slender elegance of the Yew Cherry flight Molle' that it's modelled on, and it's only about 5# heavier... so it doesn't seem very promising. But heat treating is the ace in the hole, and Hickory responds well to it, so I'm hoping for about 60# at 24 now. I've also allowed some room to reduce the length of each lever a whisker if necessarywhich will increase draw weight and reduce mass and inertia.
Maybe it will explode, maybe it won't chuck an arrow very far. I'm hoping to heat treat it and get some test shots soon, then I'll start the work of fine tuning it.
I need to prepare for a Yew harvesting road trip on Monday so I don't know if I'll have it shooting this weekend.
Just got a call from my mate JT, we're on for a bit of shooting tomorrow morning excellent. I'll make a string and give it a try out before heat treating... better check I have a suitable arrow too!
Update:- String made and tested with a 21" arrow, seems pretty quick and flew nicely through the hole... seems odd having to thread the arrow through the hole.

Flight bows are a bit of a niche thing... this one hasn't taken long to make if you discount the years of experience and the endless pondering about how I'd make it.

It's like the old joke about the retired maintenance guy who get called called in when the factory boiler stops working (or whatever piece of equipment suits your story). The lost production is costing a fortune... he walks round with a big wrench, followed by eager suited executives and accountants. He checks valves, feel pipes, listens to the boiler and eventually walks up to a water feed pipe, picks up a length of 2x2 timber that is leaning by the pipe. He whacks the pipe at a U bend and listens... there is a gurgling sound and suddenly it all springs to life.
He submits the bill, next day he gets a call from the accountant querying it... £5000 for whacking a pipe with a piece of 2x2 is a trifle excessive isn't it?
He says OK fair enough, I'll submit a revised bill.
See below:-
Striking pipe with 2x2" timber      £25
Knowing where to hit it.         £4,975
                                    total   £5,000

I also had a good trip out to a local farm shop, the farm keeps Geese and now is the time they moult their feathers. He let me have a look round the goose enclosure and pic up feathers, I got a good handfull, not many white ones unfortunately, but still a good return for an E-mail and a few minutes drive. He was a really interesting chap and it turned out he grew cricket bat Willow down along the river for a company that makes bats. We had a good old chat about wood, bows and bats, I picked up a big punnet of strawberries while I was there too. It's good to make local contacts. Which reminds me, I should wash and sort those feathers.

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