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View Full Version : String travel is not just up and down



gstudt
02-25-2011, 07:41 AM
In a perfect would I would like to see my nock travel the full distance of the power stroke inside a tube not much bigger than the nock and never touch the tube.

With that said, I challenge this team on this forum to discuss and find a way to measure left to right string travel.

Whether you know if or not must of our Martin bows have a lot of left and right string travel. In the neighbor hood of 3/4". This is part of the reason why at the static position the sight pins are generally a fair amount left of the arrow shaft. (Right handed speaking).

The TRG has helped this problem a lot. How much??? I know the TRG tunes a ton easier. I want to measure it.

I have some ideas but really hard to explain.

OK archery Engineers let me know what you think.

Thanks
Gary

elkslayer4x5
02-25-2011, 12:17 PM
I think the I've X ed lateral string/nock movement out, when I started shooting thru. :D
How're you going to measure lateral string movement? Should be able to use a draw board, instead of measuring from bow to string, measure string to board at every inch of power stroke, Something alone those lines? :)

Spiker
02-25-2011, 06:31 PM
I was thinking the bow in a shooting machine, ruler positioned horizontally, and camera lined up behind it all.
Shoot the arrow and watch the video to see how far it moves left to right...

Hutch~n~Son Archery
02-26-2011, 02:32 AM
I agree with Spiker. I have a shooting machine and watching the string movement would be simple. The only thing is the video cam would have to be able to show super slow motion.


Hutch:cool:

archerx7
02-26-2011, 04:13 AM
I was thinking the bow in a shooting machine, ruler positioned horizontally, and camera lined up behind it all.
Shoot the arrow and watch the video to see how far it moves left to right...

I think this will be the most logical way to measure horizontal nock travel along with a high speed camera.

You also have to take into consideration the style of release being used, a double jaw caliper style release will allow for a more straight forward consistant release than will a single jaw or hook style release.

SonnyThomas
02-26-2011, 05:25 AM
In a perfect would I would like to see my nock travel the full distance of the power stroke inside a tube not much bigger than the nock and never touch the tube.

I would say, Good Luck. And then question, Why? Virtually all bows shoot better than the owner can.

With that said, I challenge this team on this forum to discuss and find a way to measure left to right string travel.

This has been done by virtually every bow manufacturer of today. Hoyt and Mathews had a contest going over nock travel. This with Mathews straight nock travel and the then new Hoyt Cam & 1/2. Neither won out as both were top dogs of the archery world and still are.

Whether you know if or not must of our Martin bows have a lot of left and right string travel. In the neighbor hood of 3/4". This is part of the reason why at the static position the sight pins are generally a fair amount left of the arrow shaft. (Right handed speaking).

I doubt the 3/4" side to side travel of the bow string. The sight pins being left of the string is something that has existed for all companies. For one, the bow string is not dead center of the riser or the limbs for that matter and of single cams only the top wheel has the string centered between the limbs. And then add in the natural torque all people exert on their bow.

The TRG has helped this problem a lot. How much??? I know the TRG tunes a ton easier. I want to measure it.

You would have to explain this. Having dealt with 3 TRG systems I didn't find a thing easier about tuning on any scale.

I have some ideas but really hard to explain.

OK archery Engineers let me know what you think.

Thanks
Gary

Another pet peeve of mine. Going to extremes over nothing. Again, bows can just plain shoot better than the owner. How can there be that much of problem when those Vegas boys and girls shoot perfect and near perfect scores? John Wheeler, Martin Staff shooter, nailed down a 900 and 72 smaller than a nickle X rings to set a new record for Bowhunter Freestyle. Bowhunter; no long stab, no sight magnification.

I go to one extreme. I French tune when Outdoor target and Field is the game.

I'll go to my grave with this; Bow tuning is Secondary.

elkslayer4x5
02-26-2011, 08:56 AM
So it's not the arrow but the indian? :D

bfisher
02-26-2011, 09:52 AM
Sonny,

While I agree with you it would be nice to be able to visually see just how much lateral travel the string goes through on different model bows (slide/rod, roller guard, etc) and how much difference between longer ata bows vs. short ones, and how it correlates to cam lean.

On the other side of the coin the lateral travel couldn't be any worse than that of a finger shooter and the paradox involved. And frankly I know and have seen a few finger shooters that can shoot 590 or more on a Vegas face.

So this should just answer elkslayer4x5's question. Yeah, it's the indian.

SonnyThomas
02-26-2011, 03:24 PM
Sonny, While I agree with you it would be nice to be able to visually see just how much lateral travel the string goes through on different model bows (slide/rod, roller guard, etc) and how much difference between longer ata bows vs. short ones, and how it correlates to cam lean.
On the other side of the coin the lateral travel couldn't be any worse than that of a finger shooter and the paradox involved. And frankly I know and have seen a few finger shooters that can shoot 590 or more on a Vegas face.
So this should just answer elkslayer4x5's question. Yeah, it's the indian.

First, I would think with 3/4" lateral or horizontal nock/string movement we would have bows derailing to no end. As of the present most all derailing is shooter induced. Here, the shooter torques the bow either in drawing or letting down.

Lateral or horizontal string travel has a creature waiting to show if you really do have that movement. It's called the arrow rest. Think; Shoot through, prong style arrow rests. Horizontal center shot off. Eventually one prong or the other will show wear. No wear or very little wear would say the arrow is being driven fairly straight with the power stroke of the string. I would think if there were a fair amount of lateral or horizontal nock/string movement it would give a different horizontal launch to the arrow. But we that have shot our bows from max to minimum draw weight don't change our horizontal sight setting, only our vertical setting.

Now, for that power stroke of the string, from bow at rest to bow fully drawn. 2 thought; 1) One could possibly clamp a indicator on the bow and set it to the undrawn arrow (near the arrow rest). Draw the bow, twist to make sure torque goes to neutral and check indicator reading. 2) OR bow tested to be sure it is in fine tune. Install laser, shim to hit center of arrow at field point and center of string and draw bow. Will the laser stay on the string?

Hutch~n~Son Archery
02-26-2011, 04:27 PM
Take a look
http://www.youtube.com/watch?v=gIwZaV3e0sY
http://www.youtube.com/watch?v=jGo4FJ53nGI&feature=related
http://www.youtube.com/watch?v=9K6mnyLNOIk&feature=related
http://www.youtube.com/watch?v=hDV1pHtI7S8
Hutch:cool:

SonnyThomas
02-27-2011, 04:59 AM
Would take all day for those to load up with the dial up I have. Give details please.

Here's the thing about bows. They are mechanical, machines. Mechanically sound they repeat shot after shot. Hence, lateral/horizontal travel is consistent. Consistent meaning correct shot to shot, no error. Conclusion; No ill effect on accuracy.

Now, the compound bow has been around a few years. Every conceivable guide system for the cables has been tried, plus corkscrew cams that perform what the TRG system does. This was by Browning. Yes, draw bow and cams would corkscrew the cables off to the side. So, no guide rod, shoot through cables, double guide rod with no slides (cables slid back and forth on the rod), straight guide rods that minimized offset of cables (to the point fletching clearance became a issue), adjustable offset guide rods, plain guide rod slides, roller guide rod slides, roller guides, spring steel guide rods, stainless steel guide rods, carbon guide rods. and now the TRG system.

All the above applied to any one bow of the times have all done something, shot well and set records. Some records still standing.

Lateral/horizontal nock/string travel. If this was a problem I would think R&D would have eliminated this years ago. The compound bow and been up and running effectively for some 35 years.

Today, manufacturers are basically doing one thing, trying to catch your attention. Bows are basically perfect within themselves. Find one of the original articles of the Hooter Shooter; "Every bow we put through it shot groups of 2" or less at 60 yards." Another article of the Hooter Shooter; "/// accuracy wise, even weaker than desired spined arrows grouped outstandingly."

Bottom line; We are the problem. :mad: :D

Hutch~n~Son Archery
02-27-2011, 05:28 AM
Sonny, There is so many vid's out there that show both up and down and left and right movement. Alpine seemed to me to be the worst 3/4' might be an understatement. As far as effect on the shot, none of what I could see. But as far as an effect on noise I imagine it would be great. Some of the high speed shots showed bows worked very smooth and some very unpredictable.
Long and short of it. The smoother the draw cycle the better the bow in launch.

Hutch:cool:

copterdoc
02-27-2011, 10:07 AM
The only accurate way to measure lateral nock travel, is by measuring it in degrees, and converting it to inches.

By mounting a laser to the riser, and drawing the bow back with a precision machine (draw board, or hooter shooter), that allows the riser to pivot freely, you can measure the amount of shift in degrees. as the bow is drawn.

lateral nock travel does matter. It is a big problem, and it limits how bows can be designed.

Hutch~n~Son Archery
02-27-2011, 10:13 AM
The only accurate way to measure lateral nock travel, is by measuring it in degrees, and converting it to inches.

By mounting a laser to the riser, and drawing the bow back with a precision machine (draw board, or hooter shooter), that allows the riser to pivot freely, you can measure the amount of shift in degrees. as the bow is drawn.

lateral nock travel does matter. It is a big problem, and it limits how bows can be designed.

So if I put my bow in my shooting machine. and mount a laser to my riser and point it directly at the string. Then draw it back. This will tell me if the string has lateral movement right.

Hutch:cool:

SonnyThomas
02-27-2011, 11:54 AM
So if I put my bow in my shooting machine. and mount a laser to my riser and point it directly at the string. Then draw it back. This will tell me if the string has lateral movement right.
Hutch:cool:

Basically, yes, as long as the riser is allowed to pivot as copterdoc noted.

Hutch~n~Son Archery
02-27-2011, 11:56 AM
Basically, yes, as long as the riser is allowed to pivot as copterdoc noted.

Not a problem with my machine. I might have to try it and see.

Hutch:cool:

SonnyThomas
02-27-2011, 12:38 PM
The only accurate way to measure lateral nock travel, is by measuring it in degrees, and converting it to inches.

By mounting a laser to the riser, and drawing the bow back with a precision machine (draw board, or hooter shooter), that allows the riser to pivot freely, you can measure the amount of shift in degrees. as the bow is drawn.

lateral nock travel does matter. It is a big problem, and it limits how bows can be designed.

Agree greatly on the 2 paragraphs above, but 50/50 on the 3rd. First, I am no whiz bang when it comes to bows of any kind, but being a machinist for the better part of 35 years I've learned "checks and balances - stress in relationship to." Now, of the 3rd the problem isn't big as in bad or people couldn't shoot to save their lives. And lateral/horizontal nock/string travel doesn't just come from the guide rod. Bow string off center to limbs and riser is related to cam design.

So we can discuss this to death and beyond and we will still have to shoot our bows as we have been.

Good, bad or indifferent, I've made up mind I want a "clean" riser and don't want the TRG system if the rod hole for it has to be open to depth of the hole. My opinion, the hole is ugly and I can see edges of the slot chipping or busting out. And this TRG system was part of the origin of this thread.

I'll even go one step farther by saying I won't buy a bow with a built in quick disconnect. It's no different than the hole of TRG rod. I see the paint rubbing off now and the aluminum will start wearing next either from rubbing or some one banging things around. Screw up the opening and there is no way to fix it other than welding. Who wants their bow welded or want one that has been welded? Right along with this, I don't seen anything quick about it. Quick is 3/4 turn or like mine, snap on, snap off.

copterdoc
02-27-2011, 03:55 PM
So if I put my bow in my shooting machine. and mount a laser to my riser and point it directly at the string. Then draw it back. This will tell me if the string has lateral movement right.

Hutch:cool:
Don't point the laser at the string.

Aim it at the wall in front of the arrow.

copterdoc
02-27-2011, 04:00 PM
Agree greatly on the 2 paragraphs above, but 50/50 on the 3rd. First, I am no whiz bang when it comes to bows of any kind, but being a machinist for the better part of 35 years I've learned "checks and balances - stress in relationship to." Now, of the 3rd the problem isn't big as in bad or people couldn't shoot to save their lives.
It's not about accuracy.

It's about accuracy potential with shorter bows, higher let-off, and bigger broadheads.

It's about making a bow that is impossible with lateral nock travel. Take for instance, the Liberty I bow. It has zero nock travel, because it has laterally balanced cams, and shoot-through cables, as well as a shoot-through riser.

It would not even be shootable, if it had an offset cable guard.

Hutch~n~Son Archery
02-27-2011, 04:00 PM
Don't point the laser at the string.

Aim it at the wall in front of the arrow.

copterdoc Explain!

Hutch

copterdoc
02-27-2011, 04:04 PM
copterdoc Explain!

Hutch
Here is a video showing 3rd axis shift. http://www.youtube.com/watch?v=mXI29xQtqwc

Start at 49 sec in.

3rd axis shift, is lateral nock travel. You are pulling the bow by the string. When the string moves to the side, the riser twists and follows the string.

Hutch~n~Son Archery
02-27-2011, 04:09 PM
I forgot about that vid thanks copterdoc. When I get a chance I will have try it.

Hutch:cool:

SonnyThomas
02-27-2011, 08:12 PM
I'll go shoot my bow and have fun.....

gstudt
02-28-2011, 07:24 AM
Since I don't have time to type it all out.

Please visit www.tilttamer.com

I agree with all his findings at tilt tamer. However, he doesn't and will not tell how to measure it.

I want to measure it.

Another note, yes you can shoot 300 60xs on a 5 spot or 300 30 x's on a Vegas at 20 yards with about anything. So does it matter?? YES it does when you shoot further distance and with broadheads it matters or with less than perfect arrow spine/setup. You get the string traveling straight in all directions you can shoot about anything at any distance and group really well even when you screw up.

Can I shoot better than a poorly shooting bow. Yes, I can.

Keep up the good work. I like the thinking and opinions both ways.

SonnyThomas
02-28-2011, 11:06 AM
"Another note, yes you can shoot 300 60xs on a 5 spot or 300 30 x's on a Vegas at 20 yards with about anything. So does it (lateral/horizontal ?) matter?? YES it does when you shoot further distance and with broadheads it matters or with less than perfect arrow spine/setup. You get the string traveling straight in all directions you can shoot about anything at any distance and group really well even when you screw up."


Excuse me. What further distance or distances are you talking about?

First, average distance for taking a whitetail deers remains at 19 yards.

Second, Outdoor Target and Field has some pretty good distances, right out to 80 yards. I have seen 890s (correction) shot in Outdoor target and I've seen high 550s shot in Field. Not too long ago, last year or year before, a perfect 560 was recorded at a national event. Now, the 80 and 70 Yard Walk Ups have a 5.18" diameter bull's eye. When I shot field I prided myself in ripping that bull's eye to pieces and drilling the X heavily. In State competition I've cleaned the 80 Yard Walk Up twice, hitting the 80 yard bull's eye in two others (missing the 50 or would have cleaned them). I also cleaned the Hunter 70 yard twice, Xed it clean once. I did this with two different bows. One a true target bow, 56 or 57 pounds max. The other was my Hoyt UltraTec 3D bow where I had to de-tune it to get down to 280 fps (282 fps actual). Now, cranking at 295 fps it shot just as well. This bow has the Red Line single cam with floating yoke - yes, with so much cam lean. [Another pet peeve of mine, worrying about cam lean. Excessive, yes, correct. A little and bow shoots good, worry about something else.]

The above said, all fixed broadheads are not created equal. However, it takes quite a bit of tinkering to get some to shoot as well as a field point, not due to lateral/horizontal nock/string travel, but due to the broadheads design. I know of only one that says he gets super accuracy with a fixed broadhead cranking near 300 fps. At what distances, I don't know. A well known Professional Hunter says he can tune a spade to shoot. So tuning a broadhead should be a little easier :D

Not a believer in shooting game past 40 yards I don't see this lateral/horizontal nock/string travel issue (I will not call it a problem) doing any harm or causing excessive tuning to shoot this distance.

And then there is that Randy O. breaking balloons at 200 yards.

And then the ASA Long Shot is always in the 90 yard range and always shot with the same bows used during the events.

My longest shot ever taken was on a Delta Buffalo at 110 yards. It was a Long Shot where it was the next target after the 40 target 3D event. We were allowed 3 shots. I changed only my vertical sight setting and drilled the 10 ring with my 3rd shot.

Okay, we know we have straight string travel, but at a small degree from true bow center. What proof is out there that says we need straight string travel back to true bow center?

gstudt
03-11-2011, 04:04 PM
I collected some measurements on several bows in the same way with the same tools. It is not perfect but good enough to show the picture of how much lateral torque these bows have (generally speaking only).

I completed the measurements 8 feet infront of a right handed bow. I put the bow in the hooter shooter and started to draw the bow just enough to get it to center in the grip with pressure. I then put the hooter shooter laser tool on the side of the riser and pointed it towards the wall 8 feet away. I marked the wall where the laser was pointing. Then I pulled the bow to my full draw 27 3/4" using the hooter shooter. Back to the laser on the bow in the same spot and pointing to the wall. The laser was 100% of the time pointing to the right at full draw compared to at rest on the bows tested.

Year, Model, cable gaurd system, distance
2011 Alien Z Roller Guard 3.5" (Stock)
2010 Alien Z Off set steel rod 2.25" (Modified)
2009 Warthog Off set steel rod 2.75" (Modified)
2011 Nemisis Straight Carbon Rod 2.187" (Stock)
2011 Firecat 400 TRG 1.875 (Stock)
2011 Onza 3 TRG 1.0" (Stock)
2011 Nemisis Tilt Tamer <.5" (Same Nemisis)

I know this is not how to measure left and right nock travel properly but it is the best I can do to try and find out what is going on and if I have changed it when modifying the cable rod.

The TRG system does appear to do what it is designed to do.
The Tilt Tamer is even better just because it is adjustable. If you could move the TRG system left and right on the cable rod it would also be better than a stock TRG system.

Any guess on which bows are a fist fight to tune and which ones tune easy?

I'm currently shooting the Onza 3 and will be working to make the Nemisis better and see if I can shoot it better or as good as the onza.

bfisher
03-11-2011, 04:08 PM
I'll take a guess and say the hardest ones to tunee are those with the roller guards.

gstudt
03-11-2011, 04:13 PM
I'll take a guess and say the hardest ones to tunee are those with the roller guards.

All I know about tuning roller guards is not much.

I always take them off for this reason and never even try, but I bet it is not fun.

archerx7
03-11-2011, 06:03 PM
Its really not any more difficult to tune a roller guard bow than one with a rod and slide.....the center shot is really the only thing that changes, and it dosen't change by much.

SonnyThomas
03-12-2011, 04:17 PM
Tuned a Alien X today - roller guide. I don't care for rollers. I eye balled center shot, shot, made slight adjustment and pretty much drilled a bullet hole. Owner could not.

SonnyThomas
03-14-2011, 07:17 AM
I'm still at a loss. Do you think correcting the out of square string travel is going to improve your shooting? If so, won't it improve the next shooter's skill? And then you're right back where you were to start with. I know beyond doubt that the only way to improve my shooting is for me to improve, not the bow.