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Ever hear of this?

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Re: Ever hear of this?

Postby jeffhalfrack » Fri Jul 13, 2012 8:01 pm

This is a little off the subject,, but I just refinnished my pearson mustang and narrowed the tips and glued tip overlay (thanks 4nolz) the bow seems quicker now with the old dacron what style ff string should I make? I plan on an endless loop thanks Jeff W
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Re: Ever hear of this?

Postby marc » Fri Jul 13, 2012 8:43 pm

Not unless he made the sting from bungee cord!
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Re: Ever hear of this?

Postby LBR » Fri Jul 13, 2012 11:06 pm

Jeff, equally well made there won't be enough difference to notice on most bows.
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Re: Ever hear of this?

Postby Bender » Mon Jul 16, 2012 7:55 pm

I haven't wasted my time on looking at the link. However there is one thing I must point out. From my own testing, believe it or not, as you draw the bow, tensile load on the string does go down then climb back up as you reach the end of the draw. I know, I know, extremely counter intuitive bit it IS what happens. It happens because the force vectors change.
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Re: Ever hear of this?

Postby LBR » Tue Jul 17, 2012 10:25 am

How is that measured? I've heard that was the case, but never saw it explained.

I'm simple--put the bow on the scale, the further you "draw" it the higher the draw weight goes. May have an area where the gain is less per inch than in another, but the further you draw the more weight you are pulling. There is no point in the draw where the amount you are pulling is less at a longer draw--one inch more in draw weight = more weight you are pulling, period, anywhere in the draw cycle.

Either way, even at min and max there's not going to be enough difference to affect the 14 strand Dynaflight '97 string that was the center of the "test".

There's a reason nobody collected on that free bow offer from BW--and I think all you had to show was a 2 fps gain?
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Re: Ever hear of this?

Postby Bender » Tue Jul 17, 2012 11:55 am

Chad, you're right about draw weight, but the tension on the string goes down. Check it for yourself. I'm quite confident here, having seen it for myself. Just make 2 short strings with a bow scale in the middle, have somebody draw the bow while you watch the scale.
As for why nobody collected on the BW challenge it was because of the limitations that Beck placed on the rules. A skinny string is faster due to lower mass. However he made it nearly impossible to make a string significantly lighter than the stock BW string. I found that dropping 100 grains in string weight yeilds only a 1.7% increase in arrow velocity. Basically Beck rigged the challenge in order to ensure that he couldn't lose by mandating things like keeping the end servings the same length as a stock string, using brass nocks, keeping center serving the same length, and double serving the center serving rather than being able to use different nocks to fit the skinny string. The brass nocks and doubled center serving were the largest factors, helping to ensure that the skinny string didn't wind up significantly lighter. Also those rules placed the most mass at the nock point, helping to ensure that the arrow couldn't go any faster. As mass is added to a string, the closer you place it to the nock point, the slower the arrow.
I did finally go and look at Barbee's test. Anyway, you're also right about the "test" in that given what he was trying to test, couple with the "instrumentation" he was using, his "results" are waaaaaayy to close to being inside his margin of error. For example, his scale, marked in 1# increments is just not precise enough. It has to have an error of at LEAST +/- 1# and its probably more than that. So to declare a 2# difference when you're already +/- 1# right out of the gate before you've even measured anything is rather meaningless. To that we can then add the tape measure. He claims 3/16" difference in stretch. The tape may be accurate, but you don't get to hang your hat on one instument's high level of precision when the whole test is already limitted by another instrument's lack of precision.
Last edited by Bender on Tue Jul 17, 2012 11:56 am, edited 1 time in total.
Reason: spelling
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Re: Ever hear of this?

Postby LBR » Tue Jul 17, 2012 12:07 pm

I may try the scale thing--don't know if I could rig it to work with my digital scale.

Basically Beck rigged the challenge in order to ensure that he couldn't lose by mandating things like keeping the end servings the same length as a stock string, using brass nocks, keeping center serving the same length, and double serving the center serving rather than being able to use different nocks to fit the skinny string. The brass nocks and doubled center serving were the largest factors, helping to ensure that the skinny string didn't wind up significantly lighter. Also those rules placed the most mass at the nock point, helping to ensure that the arrow couldn't go any faster. As mass is added to a string, the closer you place it to the nock point, the slower the arrow.


Do you mean center serving? BW's stock string is flemish--no end serving.

I don't see those requirements as rigging the challenge--just comparing apples to apples. If dropping from 14 strands to 6 or 8 strands is what gives a noticeable increase in speed, it should give it with the serving, nock set, etc. the same as the 14 strand--or am I missing something here? Double-serving could add a little, but you would use a lot smaller serving--i.e., two layers of .014 (.028) vs. one layer of .025--not a big difference.

I saw so many excuses for not accepting the challenge it was a comedy--I couldn't say that any were viable. One guy said he lived...less than an hour from BW, I think, and said he could do it easily...but he "really didn't need another bow". Lol.

Just got confirmation from Roger that nobody accepted the challenge. Wish I could find the actual details.
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Re: Ever hear of this?

Postby LBR » Tue Jul 17, 2012 12:09 pm

The things that got me with Barbee, that made me strongly question his sincerety and methods, were the contradictions and the avoidance of simple questions. Made me think he knew he couldn't address those questions without shooting himself in the foot. And when you say you aren't going to get personal, and in basically the same sentence slam someone, well...speaks for itself. I don't know the guy from Adam's housecat...but I do know a little about strings.
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Re: Ever hear of this?

Postby LBR » Tue Jul 17, 2012 12:36 pm

I found that dropping 100 grains in string weight yeilds only a 1.7% increase in arrow velocity.


Was that in general, or on a specific bow? How was the weight removed?

This is one of those things that drives me nuts--or rather the claims that go with them. Unbelieveable speed gains (literally unbelieveable, as in I don't believe it), suppossedly having to move up a couple of spine groups with arrow shafts, etc. all (suppossedly) just from dropping a few strands.

You will gain some with minimal serving, dropping strands, tied-on nock set, small serving with just the nock point built up for nock fit, etc.--but it's normally nothing that will change the sport. Like everything else, the advertising draws more victims...errr, customers...than actual results. Guess I just stink as a businessman, because I'm not going to rely on smoke and mirrors and bs to make a sale.
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Re: Ever hear of this?

Postby Hank » Tue Jul 17, 2012 2:47 pm

I don't think Rick Barbee is trying to pull a snow job over on anyone. I have watched Chad's first video (if someone wants to send me the second one I would watch it) and I have watched some of Rick's video's online. If I were making strings for a living, I would make them like Chad, if I were making them for me I would make them like Rick... actually when I did make flemish strings (20+ years ago) I would put the left side of what I was twisting in a vice between leather to really get my twists super tight (like Rick does hooking the loop on a hook.) I pretty much only make endless now so it doesn't matter.

Makes sense to me you would lose a a tad in draw weight with a string that has some give to it versus one that doesn't and that alone would make a slight difference in performance.

I did talk to yorktown5 quite a bit up at the Iowa Trad Ames shoot last Memorial day. He has a Barbee string and has been making his own similar to a Barbee string and likes the results. His old Bear recurve was spitting out his arrows noticably fast @ 9gpp.

Dan Quillian was promoting (properly made) 8 strand 450+ strings years ago and that what I have pretty much stuck with.
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