Friday 27 September 2013

Twister2 and Some Chrono Results

Twister 2 got collected today. Had a great visit, his new owner came with offerings of wine, cider, cheese, fresh farm egs and a nice pair of skinny chainsaw files! Result! I made him up four arrows so he could try the bow, as the ones he's ordered haven't turned up yet.
Shooting Twister2 through the chrono was tricky, I couldn't get stable results initially as the arrows were still flexing. The answer is to shoot from further and risk skewering the chrono, or to get closer, which can still give some dodgy results. It seemed to come out at 157.7 fps, which is reasonable, not as fast as twister, but then it's a shorter draw. Also it's impossible to build your best ever bow every time!
Later in the afternoon I tried the BooYew which I knew is V fast. Now this was giving the same problem at close range and oddly I got a reading of 157.7 at one point, which make me wonder if that's some sort of artifact of the chrono?
Anyhow I went back to 10 yards, getting a nice straight flight at that distance, it managed 165fps and when I shot a light flight arrow it went up to 170fps.
You have to bear in mind it's being overdrawn and is bamboo backed, so I'm pushing it rather to the limit.
Chrono readings are a good reference, but have to be viewed with some caution. My set up is far from perfect, being indoors with a couple of lamps for illumination. Outdoors with natural light and a big backstop net would be better. Target recurves, compounds and crossbows also give much more stable readings. Their arrow flight is cleaner as the the arrow doesn't have to flex around the grip of the bow. In other words, there is no paradox. Yes, the arrow is still flexing (except for the crossbow) but that's due to the method of release etc, rather than the arrow having to bend around the bow.
Just had a nice E-mail from Peter the guy who has the bow, he's given it a good work out and is pleased with it. It's throwing the arrows a good 200 paces... and he's got a tired arm now :-)

People mix up arrow flexing and paradox...
The Paradox is that on a longbow the arrow points well to the left when first placed on the string, yet flies along the line of sight from full draw! Why doesn't it kick left???
The explanation of the paradox is the arrow flexes, so you see it's a bit like confusing cause and effect.
The Wikipedia entry has a good illustration and explanation.
To wander off on a bit of musing it's like saying 'All crows are black'. this doesn't mean all black things are crows! So the paradox is explained by arrow flexing, but not all arrow flexing is anything to do with paradox.
Anyone who wishes to argue this point is welcomed to write their own blog and expound their theories at great length! ;-)

I made some crab apple jelly too, it's a gorgeous clear red colour. It's the first time I've tried it, inspired by my big Sis making some. I only did a small batch of 4 small jars, two with Rosemary and two with Mint, should be nice on roast chicken or cold meats. I used a recipe of the internet, choosing the simplest I could find and using less sugar than stated. I got the nice pic by holding it up with the setting sun behind it.

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