Point weight and tuning thoughts...

[Mike Vines]

I would like to think alot of the finer tuning also goes with personality.  There are some people who are perfectly fine with how an arrow flies, and there are some that see that LITTLE kick when it leaves the shelf, and need to get rid of that kick.  

When people, at work, tell me they are an Engineer, I usually respond with "I have always wanted to drive a train too".  Some times it is taken with a smile, and others not so much.

Some guys just have to tinker with things.  There is nothing wrong with it, actually, it is probably a good thing, and I should probably do it more. Next time your over Steve, let me shoot a few, and tell me what you see.  It will more than likely open my eyes, and then you'll probably get me started in a whole new hobby.

[Bigriver]

I would like to be enlightened, what is the "wheel bow mentality"? What if I shoot farther than 20 yards, am I ok to tinker with stuff & match it up then?

[Tim]

The only two things I'm concerned with in a bow are noise and arrow flight.  A quiet bow means the animal is still in place when the arrow gets there and perfect arrow flight equals great penetration.    

To achieve this takes some time and effort, but well worth it in my eyes.

[bucksbuouy]

awesome post first of all

Now to answer the question- Yes I can feel the difference 15 grains makes. Not on a shot or two, but after I shoot a quiver... yeah. Yes I can. A resounding ABSOLUTELY might be a more appropriate response. I think you guys who say "no" are selling yourselves short. That being said I do shoot off spined arrows with varying point weights.

15 grains, honestly, makes only a little difference at best. Maybe 5 pounds in arrow spine? 20 grains, however, changes the spine of your arrow by about 8 pounds, if my memory serves me. Thats a significant difference in spine there gang. Now if you are already shooting 340s out of a 45 pound bow you probably are not gonna notice a difference of as much as 40 grains in point weight.

Ok Ill shut up now.

[frank bullitt]

You guys better "straighten up"!

Rob's back from Solona, and you know, you goin to get it!  

[fedora]

So what happens when I use the same broadhead year after year and when I sharpen it the grain weight changes and since I am not consistent all my bh weigh slightly different.  Awwww I just better quit shooting and get me a gun. Oh wait billets are measured in grains also.  Lol. 15 grains means a lot I'm sure but I'm not good enough to tell.  Not at 20 yards or 50.  I do tune my arrows to my setup though.

[snag]

Man, after reading all this I don't know if I'll be able to sleep tonight!    

[Steve O]

Originally posted by bucksbuouy:

15 grains, honestly, makes only a little difference at best. Maybe 5 pounds in arrow spine? 20 grains, however, changes the spine of your arrow by about 8 pounds

I am going to have to call BS on that one.

I believe a 5 lb change in spine is a   significant  change on spine.  That is an entire spine group.  

And 5 more grains to get to 20 grains?  8 pound change in spine?  Is it not a linear function?  5 grains is 33% of 15 grains.  Shouldn't it change by an additional 1.65? for a total of 6.65 pounds by your first formula?

I'd bet it is closer to  .05 pound difference in spine for 15 grains.  How come somebody that knows how to use that darn Stu's Calculator can't plug an extra 15 grains on to the point weight and tells us EXACTLY (well as exactly as the theoretical formulas driving it) what the difference in spine is    

[Steve O]

Mike, I will teach you all I know about tuning.  BUT, I have no idea how to do it on a wood arrow!  We will have to teach each other a bit    

[Mike Vines]

I've got plenty full length 60-65# already built up, now it's time to have some fun.  Like I said, mine shoot fine to me, and if I keep them full length, if they snap, I can retaper and keep on going.  As many arrows as I make, it might be better to figure out my actual length, that way my new arrow case I make will be shorter, lighter and easier to pack.

Can someone plug my numbers into Stu's calculator for me, and let me see what he says my "real" length should be.  I'm kinda interested to know.

[Mike Vines]

See, told you I was happy, and then you guys went and talked me into tinkering.  I hope I don't give up and start back with an atlatl.

Next thing your gonna tell me is that I need to start shooting carbons.

[xtrema312]

Originally posted by Steve O:
 I believe a 5 lb change in spine is a   significant  change on spine.  That is an entire spine group.  

I'd bet it is closer to  .05 pound difference in spine for 15 grains.  How come somebody that knows how to use that darn Stu's Calculator can't plug an extra 15 grains on to the point weight and tells us EXACTLY (well as exactly as the theoretical formulas driving it) what the difference in spine is      

You asked for it!    

It is 4.2# of sipine chanange for a 15 gr. point change.

[Jeff Strubberg]

Originally posted by Mark Baker:
Even less choices in Chet's day....and a whole lot less info about it.  His "tinkering" was probably not more than astute observation about what was working for him, and how he applied it.  It would likely pale by today's comparisons, simply by virtue of todays vast array of choices.  I read Chet's book when it came out (been awhile) and have to say it's one of my favorites, but I can't say that I was struck by his attention to "tinkering".   Now his skills as a bowyer were impressive.  

For me, it's easier to build bows that work for my stash of gear, than to play around with different arrows all the time.  I suspect Chet did a lot of that.   And anyone who shot arrows constantly and did a great deal of trick shooting would observe that "with big feathers" their arrows rotated X-times in 10 yards...or some such.  Writing it down probably made it seem much more of a process than it was...not unlike today, I'd say, and our impressions from all these posts about it.    

Of course, it's just my guess.   Like I said, tinkering is fine, and I have no problems with it.   I just think what some are attracted to about it, others may get overwhelmed...when there are easier solutions that can work as well many times.  So the question is, how productive is it, in regards to keeping some who might be turned off, interested in what is supposed to be a simple sport?   It's almost becoming the same as the pro-shops that sell the compound stuff and TELL you what you need, rather than realizing that all that crap is just that...crap, and not necessary.  That's my beef with it all.   And in getting back to the original premise of Steve's thread....15 grains, by most, myself included, would hardly be noticed, especially at hunting distance.   The gear itself will shoot a whole lot better than I am capable of shooting it, or in controling the numerous array of possibilities that can occur while I am shooting it.  I've been shooting for 40 years, and my form is pretty set...and I "think" I have a good grasp of "how", -- now someone "new" to trad, will not have near the frame of reference that many of us who have been shooting for years now, have, and I daresay, it probably will not be noticeable to them either.  

A good experiment to try though...and interesting.  Tinker on!   Then post the results.

There are pictures in that same book of the thousands upon thousands of arrows Chet built, and notes of his on what bow liked what weight of arrow, which fletching and what type of string.  Fascinating reading.  Apparently he also built an arrow machine that let him spine, straighten, weigh and spin test on one piece of equipment.  Would have loved to see the plans on that!

And lest we stray too far from the original premise of the thread, in my ill tinkering heart I think it would be hard to detect the difference in 15 grains of point weight, unless you are already treading the edge of a spine problem. That's well within my range of shooting error, anyway.

[Steve O]

[/QUOTE]You asked for it!        

It is 4.2# of sipine chanange for a 15 gr. point change. [/QB][/QUOTE]


No kidding.  The only change was 15 grains to the point weight and it changed the arrow spine 4.2#.  I'll be darn.  

What arrow specs did you start with?  A 26" 2219 aluminum with a 100 grain point or a full length .600 carbon with a 300 grain point?

Big difference isn't it?

Will that thing theoretically tell you how much the spine will change if your draw varies by half an inch?

[Prairie Drifter]

Originally posted by Steve O:

You asked for it!        

It is 4.2# of sipine chanange for a 15 gr. point change. [/b][/QUOTE]


No kidding.  The only change was 15 grains to the point weight and it changed the arrow spine 4.2#.  I'll be darn.  

What arrow specs did you start with?  A 26" 2219 aluminum with a 100 grain point or a full length .600 carbon with a 300 grain point?

Big difference isn't it?

Will that thing theoretically tell you how much the spine will change if your draw varies by half an inch? [/QB][/QUOTE]


Steve,
It will tell you how much the spine required for the bow will change

[Steve O]

Well then, Todd, could you put that arrow back in that you used to get the 4.2# and run it with a different poundage for the bow you were using a half inch longer and shorter than the draw length you had in originally?

I find this all pretty fascinating    

[Mike Vines]

Who knows how to use the calculator that can input my numbers for me to figure out my correct length arrow?

[xtrema312]

I can try some stuff to see how it changes.  That was one of my bows and my carbon  arrow.  I do not shoot what it says by the way.  I shoot 20# under spine with 400's.  500’s are close.  I also find that carbon length and point weight do not match up for how they change flight.  Length is a bigger factor with carbon than point weight for me.

I will run my bow and arrow with draw weight, length and point variables.

[Prairie Drifter]

Originally posted by Mike Vines:
Who knows how to use the calculator that can input my numbers for me to figure out my correct length arrow?

Mike,
 Need your bow stats, ie; type of bow, riser cut,string type and strand #, poundage at your draw and what your draw is.

[Steve O]

Originally posted by xtrema312:
I can try some stuff to see how it changes.  That was one of my bows and my carbon  arrow.  I do not shoot what it says by the way.  I shoot 20# under spine with 400's.  500’s are close.  I also find that carbon length and point weight do not match up for how they change flight.  Length is a bigger factor with carbon than point weight for me.

I will run my bow and arrow with draw weight, length and point variables.

That will be great for comparison sake.  What you just said above further degrades the confidence I have in the numbers "the calculator" spits out though.  For that thing to be accurate, it would have to incorporate physics, dynamics, and mechanical vibration equations.  From what I have seen of it, it looks like it is more on the line of linear equations...


A couple of other "general" things I have noticed which may or may not help somebody when they do a search on "tuning" and this thread pops up:

Weight added to the point of the arrow has a much more drastic affect on spine (decreasing) than does adding it to the nock end (stiffening).

Weight tubes make arrows do crazy things!