Level nock travel?
01-16-2002, 12:44 AM
#21
Join Date: Feb 2003
Location: calgary alberta canada
Posts: 250
RE: Level nock travel?
Is level knock travel the reason why most competitive target archer's shoot twin cams?
I have heard Pinwheel talk about super tuning and how you can't do it with a single cam bow. ???????
Good shooting.
Dylan
>>>>--------o-->
I have heard Pinwheel talk about super tuning and how you can't do it with a single cam bow. ???????
Good shooting.
Dylan
>>>>--------o-->
01-16-2002, 04:46 AM
#22
Typical Buck
Join Date: Feb 2003
Location: .. NH USA
Posts: 970
RE: Level nock travel?
Murry and Dylan both hit on combined points. To answer both questions, yes, most competitive archers shoot twins because of their extreme tunability over conventional solo designs. The only ones that do not are the 3D Pros, and because most are simply shooting what the factory puts in their hands. BUT, for longer distance shooting, the ability to "supertune" a twin provides a significant advantage. Any bow can be supremely accurate in the right persons' hands, but the twins offer a distinct advantage in the tuning dept. and can only be an asset if one can tune a bow to their exact form and arrow configurations, even holding. Good shooting, PW12
01-16-2002, 12:49 PM
#23
Join Date: Feb 2003
Location: Chesapeake VA USA
Posts: 135
RE: Level nock travel?
Ossage, your contention that "...this whole issue was invented to get traction on Mathews at a time when they were a rapidly rising company because of their single cam." is really reaching. If you can make that statement then one could then say that timing (synchronizing) of a 2 cam is not really necessary (to an extent) because when they are not timed, the major effect is the nock travel gets that rise/fall thing going on. Hmmmm. <img src=icon_smile_wink.gif border=0 align=middle> That then blows the whole premis of why the single cam is so good out of the water. Needless to say, nock travel is important, for both types.
01-16-2002, 06:25 PM
#24
Join Date: Feb 2003
Location: calgary alberta canada
Posts: 250
RE: Level nock travel?
They still haven't got all of the kinks out of twin cams, I wonder how longer the "wonder drug" single cam will take to get all the problems, like nock travel ironed out. As I see it, with a twin cam you have the advantage. You can super tune, The travel of the bow itself is better, straight foward rathers then bottom end kick outs, smoother draw cycle, can be more forgiving.
Good shooting.
Dylan
>>>>--------o-->
Good shooting.
Dylan
>>>>--------o-->
01-16-2002, 08:03 PM
#25
Join Date: Feb 2003
Location: sabina oh USA
Posts: 7
RE: Level nock travel?
I was recently attempting to tune a fiend's Mathews MQ1 and wasn't having a great amount of success. No matter what spine I tried what kind of rest or rest and nock position The thing would not make a decent hole in the paper (yea I know, but it's important to this friend). Finally I told him that the only fix was to twist the string to bring the cam back into proper time. That's correct, timing was the answer even on a one cam. He resisted because his draw length was exactly what he wanted and he did NOT want to shorten it. Even though I recommended the opposite he is now shooting a shorter draw length and making good holes in paper.
01-16-2002, 08:25 PM
#26
Join Date: Feb 2003
Location: Baltimore Maryland USA
Posts: 1,385
RE: Level nock travel?
Murray: The way Larry apparently did his test is typical of many. I have talked to Larry and highly respect him and his opinions; however, on this style of testing, I must respectfully offer some criticism.
When we do the testing on an Apple Ultra Tuning Machine, we pull from the absolute center of the axles. This is done so as to establish a datum that can/will be the exact same test method no matter what the design of the riser.
There is a lot more set-up to getting the bow positioned properly for the nock travel test. It is done with precision so that the results can be compared using the same set of standards. If you pull a recurve bow from the center, you will get straight and level nock travel. If you pull a crossbow from the center, the same results. If you pull a two cam bow of any design cams from the center, ditto. If you pull a single cam (except for one particular design), the results will be quite different. Not only will it vary in both the level and straight modes; but, it will vary extensively from one manufacturer to another.
My criticism of anyone who pulls from the nock position is that they have no "datum". The nock position, if they use a bow square, will vary from bow to bow. It also becomes somewhat of an assumption as to specifically where that nock position must be.
Good work on your friend's MQ1. I have corrected many times this same problem with customer's bows. BTW, the timing issue can also affect the centershot positioning when a marginally spined arrow is being used.
When we do the testing on an Apple Ultra Tuning Machine, we pull from the absolute center of the axles. This is done so as to establish a datum that can/will be the exact same test method no matter what the design of the riser.
There is a lot more set-up to getting the bow positioned properly for the nock travel test. It is done with precision so that the results can be compared using the same set of standards. If you pull a recurve bow from the center, you will get straight and level nock travel. If you pull a crossbow from the center, the same results. If you pull a two cam bow of any design cams from the center, ditto. If you pull a single cam (except for one particular design), the results will be quite different. Not only will it vary in both the level and straight modes; but, it will vary extensively from one manufacturer to another.
My criticism of anyone who pulls from the nock position is that they have no "datum". The nock position, if they use a bow square, will vary from bow to bow. It also becomes somewhat of an assumption as to specifically where that nock position must be.
Good work on your friend's MQ1. I have corrected many times this same problem with customer's bows. BTW, the timing issue can also affect the centershot positioning when a marginally spined arrow is being used.
01-16-2002, 11:09 PM
#27
Join Date: Feb 2003
Location: Central Louisiana
Posts: 144
RE: Level nock travel?
Len, I am curious about something. If you take an average single cam bow and pull it from the center point axel to axel (as you do)and trace the nock travel then take that same bow and pull it from a point in line with the center of the berger button/rest mount hole 90 deg.(nock point) to the string what will the difference be in the nock travel path trace? I hope I asked this right and it makes sense.
01-17-2002, 12:57 AM
#28
Join Date: Feb 2003
Location:
Posts: 520
RE: Level nock travel?
Len I am in Ontario, and look forward to being down your way some day.
From what I understand of parts of your explanation of level nock travel, one of those Japanese bows with essentialy radicaly dissimmilar limb lengths would be guilty of unlevel nock travel. If so, that kind of gets to the point that the issue is a non-issue, at times. Of course with compounds we aren't in Kansas any more, so I don't know what happens there.
Len in addition to your extensive testing of nock travel as to where it is present, and by how much, have you been able to track any corelation to performance, and to what degree? So for instance on spine, is material.
One thing I hadn't thought about in years was that the early Mathews ads used to make a big deal about where they located the handle. I can't remember the point, but as a guess I would say they put the arrow at the middle, and the grip low, contrary to the then comon practice. Do you recall Len? Is this placement of the handle, which I would guess is comon on short bows today (and certainly not a "novel treatment as the IP lawyers say), also part of the nock travel issue?
From what I understand of parts of your explanation of level nock travel, one of those Japanese bows with essentialy radicaly dissimmilar limb lengths would be guilty of unlevel nock travel. If so, that kind of gets to the point that the issue is a non-issue, at times. Of course with compounds we aren't in Kansas any more, so I don't know what happens there.
Len in addition to your extensive testing of nock travel as to where it is present, and by how much, have you been able to track any corelation to performance, and to what degree? So for instance on spine, is material.
One thing I hadn't thought about in years was that the early Mathews ads used to make a big deal about where they located the handle. I can't remember the point, but as a guess I would say they put the arrow at the middle, and the grip low, contrary to the then comon practice. Do you recall Len? Is this placement of the handle, which I would guess is comon on short bows today (and certainly not a "novel treatment as the IP lawyers say), also part of the nock travel issue?
01-17-2002, 08:17 PM
#30
Join Date: Feb 2003
Location: Baltimore Maryland USA
Posts: 1,385
RE: Level nock travel?
8Pt: "If you take an average single cam bow and pull it from the center point axel to axel (as you do)and trace the nock travel then take that same bow and pull it from a point in line with the center of the berger button/rest mount hole 90 deg.(nock point) to the string what will the difference be in the nock travel path trace?"
It actually looks worse as you get away from the center of the string towards the nock position. The higher you would go, the worse it would get. Determining that exact point on the string where the nock would cross the berger hole is more difficult and wouldn't yield data as repeatable/comparable by using the same datum on all bows. Also, while it is on the machine, we can do many other things like check for weak limbs. I hope I have answered your question correctly.
Ossage: "Len I am in Ontario"(I really would have sworn you hailed from Missouri!<img src=icon_smile_wink.gif border=0 align=middle>) "and look forward to being down your way some day." Please, by all means, stop by the shop.
"From what I understand of parts of your explanation of level nock travel, one of those Japanese bows with essentialy radicaly dissimmilar limb lengths would be guilty of unlevel nock travel." Not necessarily so. If I remember what they look like, they have not only different length limbs but also different diameter limbs; thereby making the draw weight different from top to bottom limb. Why don't you send me one of those bows and I'll check it for you? . "Of course with compounds we aren't in Kansas any more, so I don't know what happens there." No, like I said above, I think we're in Missouri! <img src=icon_smile_big.gif border=0 align=middle>
"Len in addition to your extensive testing of nock travel as to where it is present, and by how much, have you been able to track any corelation to performance, and to what degree?" I can tell you that the earlier one cams, as I stated many times, was horrible when compared to the newer one cams. This was, in part, a major problem to good arrow flight and selection. The degree of error was a major variable, as I also said, and correlation would be impossible unless you told me to what we had to compare it. If it wasn't a problem, why then did they "fix" it?????
As I indicated to 8Pt above, the location of the nocking point can have an affect on the nock travel. The one cam showed a much more severe affect than did the two cam bow. For test purposes, I used a one cam and two cam version of the same model bow.
I hope this answers all you questions correctly. Let me know when you're shipping that Japanese bow. <img src=icon_smile_wink.gif border=0 align=middle>
It actually looks worse as you get away from the center of the string towards the nock position. The higher you would go, the worse it would get. Determining that exact point on the string where the nock would cross the berger hole is more difficult and wouldn't yield data as repeatable/comparable by using the same datum on all bows. Also, while it is on the machine, we can do many other things like check for weak limbs. I hope I have answered your question correctly.
Ossage: "Len I am in Ontario"(I really would have sworn you hailed from Missouri!<img src=icon_smile_wink.gif border=0 align=middle>) "and look forward to being down your way some day." Please, by all means, stop by the shop.
"From what I understand of parts of your explanation of level nock travel, one of those Japanese bows with essentialy radicaly dissimmilar limb lengths would be guilty of unlevel nock travel." Not necessarily so. If I remember what they look like, they have not only different length limbs but also different diameter limbs; thereby making the draw weight different from top to bottom limb. Why don't you send me one of those bows and I'll check it for you? . "Of course with compounds we aren't in Kansas any more, so I don't know what happens there." No, like I said above, I think we're in Missouri! <img src=icon_smile_big.gif border=0 align=middle>
"Len in addition to your extensive testing of nock travel as to where it is present, and by how much, have you been able to track any corelation to performance, and to what degree?" I can tell you that the earlier one cams, as I stated many times, was horrible when compared to the newer one cams. This was, in part, a major problem to good arrow flight and selection. The degree of error was a major variable, as I also said, and correlation would be impossible unless you told me to what we had to compare it. If it wasn't a problem, why then did they "fix" it?????
As I indicated to 8Pt above, the location of the nocking point can have an affect on the nock travel. The one cam showed a much more severe affect than did the two cam bow. For test purposes, I used a one cam and two cam version of the same model bow.
I hope this answers all you questions correctly. Let me know when you're shipping that Japanese bow. <img src=icon_smile_wink.gif border=0 align=middle>