Visitors and a Good Chat

My old friend Roy from Med' Soc' came over for the Plum which now has a handsome black leather grip, he brought a friend David along who was interested in having a Yew ELB made.
He was also very interested in flight arrows so we had a good chat and I showed him some of my slo-mo footage of flight arrows being shot from the shooting machine. David was taking about the concept of "centre of effort" which is from sailing, it turned out we mostly agreed with each other but the semantics of describing our thoughts got in the way somewhat!
He'd tested some arrows by dropping them horizontally from a high window and wanted them ideally to fall whilst remaining horizontal or turn  slightly nose down (He can correct me if I'm wrong). I said that my corresponding test was to lob 'em up in the air underarm and I wanted them to arc over at the top of their travel and to fall nose down.
It's an interesting topic as, once the arrow leaves the bow it is falling under the influence of the acceleration due to gravity, BUT if it is shot up at 45 degrees, that angled velocity is superimposed on the fall, and until the downward velocity has increased sufficiently to overcome the upward component it still goes up.
So, is it falling relative to the air or not... or is it just falling on the way down? Do you want it to present as much resistance to downward motion as possible to slow its fall (e.g falling whilst horizontal) whilst having as little resistance as possible to forward travel? Or do you always want it lined up with the direction of travel (feel free to comment... I like comments, it shows me that people read this!).
Much of this has been addressed empirically by Clarence N Hickman using his shooting machine in the early 1900s.
I'm not going to be drawn into venturing an opinion, I'll only say that my flight arrows have their point of balance just forward of the geometric centre by about 3 or 4 % and that I've seen arrows with the balance point too far back fly most erratically turning and diving at right angles!
I use the balance point (centre of gravity) and the geometric centre as these are both easily measured.
Enough of that!
(We also had a go with the Chinese repeating crossbow of course).

Having discussed making a bow it motivated me to sort through some billets one pair looked suitable, a much fatter pair that I will also splice up had some of the dreaded blue grey discolouration (even the good pair had a little). As the billets are cleaned and reduced in dimension the wood looked better, so hopefully any bad stuff is only on the surface. It won't matter too much for a 40 pounder, but for a warbow a clean sound back is critical.
I got the billets for the 40# spliced up and have been working it down to stave that flexes. Mind, it's so long since I made a 40# ELB it's still about warbow weight! Not quite ready for the tiller yet.
Note on the pic of the billets prepared for splicing, they need a nice clean flat surface so that the sit nicely on the bandsaw to give decent straight cuts, also clean flat faces are easier to mark out.

On an unrelated topic... a story was told to me (I try not to report stuff second hand , but this has a purpose).
Someone said that they'd had no joy patching damaged bows, and they'd tried long patches but even those failed.  The other person replied that they'd seen me do it a couple of times and that I spend a lot of time getting a perfect fit, holding it up to the light and repeatedly checking until its a good fit.
The response was words to the effect of "I haven't got time to mess about doing all that!"
What??? How can you have the time to repeatedly do something badly and have it fail, but don't have the time and patience to try doing it right? Bonkers!