Thursday 19 May 2016

Turning Flight Arrow Points

This is really an aide memoir for me as I don't use my little lathe that often and I forget how I did it last time. The critical bit is turning down the neck, if the right end of the work isn't supported it will just bend or snap off. The female centre I use is just a scrap of brass rod with a hole in held in a chuck which is a bit big. When I bought that chuck on line I thought bigger was more useful, but it's not always the case, as it stops me getting the tool in close without it overhanging the tool post a long way. I expect any of you who are skilled machinists will see I'm probably doing it all wrong. Any hints or suggestions gratefully received.
I was surprised how light the point is, I could have gone a bit longer on the neck and point maybe.
Once the point is glued into a shaft they will be finished together with very light cuts to blend in a smooth taper and get a good finish.
The point of all this is to try different spines from 120# warbow (and assorted other bows) to hopefully get a clean flight.
I have a theory, I've since found it is also held by others, that you need a much lower spine than one would think for flight arrows which have to flex round the bow (as opposed to being centre shot). This is due to the lightness of the arrow and specifically the lightness of the point. There is much less inertia resisting the huge initial acceleration and thus less bending force.
I had one bloke on a Facebook group telling me I didn't know what I was talking about in a rather abrasive manner... I left the group.
I'm happy to indulge in reasoned argument or discussion, but there seem to be few people these days who understand the rules of arguing logically. You have to counter a point or explanation with facts or logic, calling someone an idiot doesn't really achieve much.
I'm happy to share my knowledge and lack of it, and I'm quite happy to be wrong!
But I wasn't going to waste time trying to explain something to someone who couldn't distinguish between a 1/4 pound arrow and a flight arrow.
I've glued in one of the points and blended it in on the lathe, (slide set to 5 degree angle) I could possibly taper it a bit more. The arrow weighs 499.8 grain which is convenient, doubtless it will be a tad over 500 when it's finished. The balance is nicely just fore of centre.

2 comments:

  1. Sadly, FB does attract a fair number of ignorant (in both senses) people!
    I'm with you - I would have thought it was quite logical that a lighter point would mean a lower bending force on the arrow (lower mass at the front to resist the applied force at the rear) and therefore (all other things being equal) require a lighter spine to match a given bow.
    Finished article looks nice - I've got some Tonkin Cane shafts so I might have a go at making my own points similar to yours ;-)

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  2. I bought some white Goose feathers online but they are a bit small and feeble (not primaries) I'll give 'em a go, they may be ok for low profile flights. I'll blog up how they perform.

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