Author Topic: First flight arrow. (Read 1253 times)

superdav95 · « **Reply #15 on:** February 09, 2026, 12:53:16 pm »

Quote from: Del the cat on February 09, 2026, 04:55:54 am

Quote from: willie on February 08, 2026, 06:38:52 pm
Quote from: superdav95 on February 08, 2026, 12:07:08 pm
. Right now the flexion of the shaft measures .525” on my little home made spine tester which put it’s around 50lbs.

that deflection is with a 2 lb weight?

where does the 50 come from?

Wow thanks Del. I overlooked this important detail. Thanks for sending this. I’ll be making some adjustments.
Might be worth reading this, as there are two very different ways of "measuring" spine.
https://bowyersdiary.blogspot.com/2017/10/spine-measurement.html
Del

superdav95 · « **Reply #16 on:** February 09, 2026, 04:39:15 pm »

Ok so after redoing my math thanks to Del btw… I now have 4 shafts ranging from 30# to 50#. This should give me a good idea what this bow likes. The weights are varied a bit range from 205grains to 233grains. I’ll get them sealed up here next few days and then get them fletched.

Badger · « **Reply #17 on:** February 09, 2026, 05:37:04 pm »

On short flight arrows I have never heard of actually calling the number for spine. Most people just talk about defection because the actual spine is so low. Cutting an arrow from 30" to 25" will add about 25# spine to an arrow. That's why we measure at 22".

superdav95 · « **Reply #18 on:** February 20, 2026, 09:21:34 pm »

So i ended up with 5 flight arrows all fletch with goat skin parchment. I used my fletch jig to position the razor blade in place of where a featther would be and drew a line and then rotated the nob on jig drew another line and so on. this gave me a line to follow for my cuts and inset the fletchings. worked well enough for my needs. i kept my fletchings very small. i fire hardened the tips and sealed them up with super thin ca glue. the Shafts are all barrel tapered and the weights range from 187grains for the 30# arrow to 228grains for the 50# spine arrow. The math the had me stumped initially on this my issue in figuring out the spine stiffness and once i got my head around that i was good. basically with a peg distance of 22" = 22 divided by the deflection in inches. for the 30# spine shaft this deflection was .725" which is pretty close to 3/4" deflection. 22/.725"= 30

my goal for these arrow is to see what shoots the cleanest and farthest with my bows. that wont likely happen till spring. I hate waiting.