Sunday 10 August 2014

Stupidity in the Higher Primates

It absolutely stonked down with rain so I resigned myself to improving my Chrono' set up and testing the Spliced Yew bow.


I made a cardboard light shield which directs the light directly over the sensors of the chrono' . I also moved the ceiling hook nearer to the centre of the garage to give an easier shot.
Time to test it, I thought I'd use a short slowish bow for initial tests (a very long bow can foul on the ceiling). I picked up Monkey Bow but forgot it's only tillered to 26"...  BANG the tip of the upper limb sheared off when I took it to the full 28".
I may well repair it as it's such a fun show piece, Maybe I'll do slightly longer levers so it can be drawn to 28".

Anyhow, on to test the Yew bow, the chrono' works much better giving very clean reproducible results. I probably need to pick up the lower edge of the arrow netting and drape it over the wire to give extra thickness to catch the arrows. They drop to the floor having hit the netting, which is better than having a target there and risking them smashing each other.
With the 11/32" shafts I got 170 fps and you can see with the 5/16" shafts I got 173.7 fps, slightly faster but less comfortable on the bow hand.
This compares well with 178fps for my refurbished Yew bow which was heat treated and is substantially shorter.
I think I'd probably get a slightly higher speed with a better loose, the prob' is I have to splay my legs out to avoid hitting the ceiling. I'll update this if I get a better result.
Here we are, a couple of higher results. Note in the 184fps the left wooden spill I use as a marker indicating where to shoot has been shot off, this indicates the arrow was probably flexing wildly (or I can't shoot straight!) and may not have gone cleanly through both gates of the chrono, thus giving a false result. It is prudent to discard any suspicious readings as spurious. I am willing to believe the 178.3 as it was a nice clean snatch loose as I'd use if flight shooting and both spills are still in place.  It's safest to take the average reproducible reading. No point in claiming optimistic freak results.

The chrono actually comes with steel rods, but they don't survive very well! they are fine if you are shooting an air pistol or a fire arm. The spills are from an old split cane roller blind and are very hand for all sorts of things like mixing epoxy.


Update:-
Monkey Bow will rise again (Oooooh Ah Ah Ah!).
I've started work on making new levers to splice onto the tips. The limbs have been cut to the same length.
The re worked bow will be about 3.5" longer, hopefully that will get me to 28" draw. All just a bit of fun experimentation, but it will be nice if he can shoot again. Ideally I'd use Ash with curved grain to follow the curve of the levers but I don't have any suitable (I'll keep my eye out for any curved limbs that fall over Winter for future use). Anyhow, I'll play it by ear and may add a slim belly or back patch to add extra support to the splice, or maybe just a binding of linen thread soaked in epoxy, that will prob' be simplest. This is really just random tinkering, but that's how we learn and discover stuff... maybe I'll discover a new antibiotic during the process? or perhaps I'll stumble on time travel? Although I'm not sure time machines are generally of wooden construction....
Sorry I'm getting hungry and wandering off into flights of fancy.


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