nodes...

[Lynn]

Pacecil
Your first picture shows us around 220 degrees of barrel movement with the node at 180 degrees.
Your second picture shows us the same thing only with a kink or flat spot at 180 degrees.
Your 3rd picture is the same.
Your 4th picture is the only picture close to what Bill describes.
I will use degrees instead of node and anti-node so I don't confuse you.
Bill is talking about the bullet exiting at 180 degrees like in your fourth drawing.
If you were to measure the barrels curve and plot it from 170 degrees to were the bullet exits at 180 degrees it would show a certain amount of amplitude.
If you then added a tuner to the end of the barrel weighing 13 ounces and the bullet once again exited at 180 degrees plot the same barrel curve from 170 degrees ro 180 degrees and the curve will appear flatter or wider.Wider in this case means if we extended the curve so it now ecompasses 360 degrees the circle created would have a larger radius.

If we put the anti-node or in this case 270 degrees at the muzzle when the bullet was exiting the barrel would be at its slowest point in the vibration pattern.If we then moved to 260 degrees and plotted a curve to the muzzle at 270 degrees it would have a certain amount of amplitude.If we once again added our 13 ounce tuner as above and re-plotted the curve from 260 degrees to 270 degrees the curve would once again be flatter and wider.See wider above.
In all of the models I have looked at they show the node and anti-node traveling down the barrels length but only your 4th picture shows one at the muzzle while the bullet exits.The rest show the bullet exiting at some point between 180 degrees and 270 degrees not at 180 degrees or at 270 degrees.
Waterboy

 

[Vibe]

Actually, you didn't answer, and according to the website you were online. Possibly, you chose to go back to work instead of screwing around. I'm gonna rephrase that last statement. It was made in haste. You are knowledgeable but just a little stiff in your thinking.

My computer is often on and logged in while I go to bed during the day. Be careful with assumptions. I've answered as best I could. LOL. I'm stiff, There's a pot calling the kettle black.
Watch again the animation of the Clamped-Free (Cantilever Beam) at
http://paws.kettering.edu/~drussell/Demos/Flexural/bending.html
If you can find where the shape EVER looks like the 2nd drawing here
http://benchrest.com/forums/attachment.php?attachmentid=8434&d=1251769026
Which is exactly what Bill claimed to be happening - and demonstrate it here. I'm sure we would all be grateful.

But (lynn) you will also notice that the "free" swinging end past the node does NOT remain parallel to the axis of oscillation like in the other drawings posted by pacecil either - it also changes in angular direction.

And you pretty much admitted that there is nothing wrong in the phrase "parallel node". That's all I needed to know.

You are very skilled at reading in just exactly what you wish to see then. And even then you must have had to put quite some effort into it.

The opinion of 10,000 men is of no value if none of them know anything about the subject.
- Marcus Aurelius--

 

[martin hammond]

Beau, varmit Al, one last try. if you time or tune a rifle with one velocity of ammo and that ammo is outstanding, with a variaton of 5 fps is the rifle really tuned? nipper just made a point that a lot of shooters run into. a rifle is bought and with that rifle is sometimes given tuned ammo. once that ammo is used then the rifle goes to pot. it takes me several hours and a bunch of ammo to tune a rifle, if it can be done faster and with less ammo I would like to know. and I don't think a person has to have a phd to be at the top of their feild. I think Bill Calfee, Harrry Deenen and others are head and shoulders above most and would like to know what they see that most of us don't. this stuff with nodes goes right over my head, as I'm sure it does to a lot of us. most feel a tuner helps good ammo and just want to be knowlageable not to mess it up.

 

[Tom C.]

gosh marty what time do you get up? all i can say is i don't much about
how this stuff works but it does. marty thanks again for tuning my 40
it shoots better than it ever has, come on down to the match in a couple
of weeks and i'll show you. hehe.

 

[martin hammond]

Tom, I'll see you in 2 weeks, one thing with shooting there is new perspectives all the time. if you look at the threads that get the most looks they always deal with ammo testing and tuning a rifle.

 

[Tom C.]

so you're saying it's not just because it's a beau, lyn, calfee thread.
well heck marty start your own. call it HOW I TUNE MY RIFLES works
for me. we used to have an old backwoods guy here that could point
and shoot grouse on the fly with his old .22 rifle. i said how'dyou do that,
he said i don't know but as long as i get 'em i don't care. i got somethin'
for the table tonight. you don't have to be a rocket scientist to press
the ignition button.

 

[Lynn]

Vibe
I am trying to bring the smart guys like yourself TOGETHER with Bill Calfee's writing style so TOGETHER you guys can help me out.I want all of the credit to go to the smart guys and Bill Calfee I just wish to shoot my rifles with the tuner adjusted properly and trounce the competition at each and every match.
You guys keep posting the second picture by Pacecil and it is not what Bill Calfee shows in his pitcure.PLEASE STOP POSTING IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!

In Bills picture the node is 180 degrees from the receiver AND the muzzle is 180 degrees from the receiver.The node and the muzzle are TOGETHER!!!!!!!!!!!!!!!!

If you draw a line of the vibration pattern from 160 degrees to 180 degrees and you then dampen the vibration pattern what happens to your line????????
It gets flatter and wider does it not???????????

Now as you already know the node is around 2-7/8 inches back from the muzzle without a tuner.If we add length to the barrel by installing a weighted tube do we move the node to the muzzle or do we get closer to the anti-node or to help out Pacecil do we move closer to 180 degrees or 270 degrees along the vibration pattern??????
Shhheeessshhhh.
Waterboy

 

[Boyd Allen]

I think that there is a lesson here. If Bill had simply said that he has been able to configure a tuner so that it does not require any further dial-in after the initial setting, and described his procedure, without any discussion about why or how it works, think of all the "ink" and heated discussion that would have been saved. Everyone could have come up with his own reasoning as to how it works. As long as the procedure was accurately described, and it worked, what would have been lost...and gained. Sometimes, saying "I did this, and this is what happened, and it has happened that way repeatedly." may be a better approach, even if you "know" how it works. Just a thought...

 

[Fred K]

Good Points Boyd
Fred K

 

[Vibe]

You guys keep posting the second picture by Pacecil and it is not what Bill Calfee shows in his pitcure.

Other than the position - where Bill moved it to the muzzle - yes it is. It still shows the "flat kink" that cannot be formed.

The node and the muzzle are TOGETHER!!!!!!!!!!!!!!!!.

that is the objective of Bills endevors.

If you draw a line of the vibration pattern from 160 degrees to 180 degrees and you then dampen the vibration pattern what happens to your line????????
It gets flatter and wider does it not???????????.

Flatter is important - "wider" is a side effect of that where "flat" is all amplitude less than X, but the node itself is still just a single point.

Now as you already know the node is around 2-7/8 inches back from the muzzle without a tuner.If we add length to the barrel by installing a weighted tube do we move the node to the muzzle or do we get closer to the anti-node or to help out Pacecil do we move closer to 180 degrees or 270 degrees along the vibration pattern??????

Waterboy

With a large enough weight you would be putting an inertial "fix" to the muzzle end of the barrel - but at that point you would be tuning closer to a 1/4 wave free swinging set up due to the increased droop from gravity cause that would be a very large weight.

Bills claim of a tuner requireing no further adjustment has yet to be substantiated by reports to this forum - even for "just" the limited velocity ranges involved in rimfire- at least as far as standing up to various other changes over time. I can go with a tune that will self compensate for some range of SD. But it would seem that changes to overall dimensions due to temperature changes might still cause it to require some seasonal tweaking.

Lynn, as far as moving an anti-node to the muzzle...I don't think that that would be of any real benefit. Though the Browning Boss method was to modify the timing of the "beyond the node" swing to the point that the bullet exits on the end of the upward swing at the "stopped" point. With the slowest bullets in the SD exiting at the true stopped point and faster ones slightly lower - resulting in a self closing group at a given range.

 

[B. Harvey]

I believe the 'parallel node' Bill refers to is simply the old, 'make a pencil bend trick' we all learned as kids. The node is a finite point of very small length, not the .5" or so some talk about. NO, set your rifle up on a rest and place a small diameter wire on the muzzle, or slightly behind, then start tapping the barrel and the wire will move to the node.

A fixed-free beam is a quarter wave machine, a fixed-fixed beam is a half wave machine. If you look at where the node is on the barrel (without a tuner), and measure back to the action (other node), this is your half wavelength.

An 18" half wave will equal a frequency of 375.1094 Hz at 68 F. This half wave equals a 36" full wave. Since you would have another 4.5" of barrel, this would equate to 5/8 of a full wave. You would think getting the middle of the anti-node to the muzzle would be of great benefit, but you would need to make your barrel a true 1/4 wave machine to do it.

Since our barrels are telling us we are at the 5/8 mark, if we could get a profile large enough to increase the frequency to get another node in the barrel, then we would be closer.

To get closest to having the anti-node at the muzzle, you would have to move the node rearward. I know of no way to do this.

I don't think it would help much seeing as how each rifle is it's own law.
I have a friend with a rifle identical to mine, his is tuned at 5.5 oz, and mine at 10 oz. Proves there is no use worrying about where that stupid node is.

 

[D R Greysun]

Nodes, anti-nodes, parallel-nodes & commodes....!

Mr. Bill Calfee, contemplating the 'node', 'anti-node' and why God gave him the gift to build 'killer' RFBR rifles (& pistols). Y'all have a large holiday and take some time to node off.

D R
Shoot straight, shoot often!

 

[pacecil]

Lynn, with reference to post 121

The use of degrees to denote a position along the barrel is causing me a little bit of a problem. This may depart from a great many opinions given in past, but the barrel is not bent into the shape of a sine wave as it vibrates. It probably comes closer to being just a series of parabolas joined together. Lets just agree that "180 deg" means the position of a node, but forget about using degrees to correspond to any other position.

Now with that out of the way lets get to your basic question. That is ....How is the barrel bent without a tuner as it passes through the node compare to how it's bent when you add a tuner? Now bear with me on this next statement. When we talk about "barrel passing through node", we are talking about the barrel stopped in an instant of time. That instant is when the barrel has reached maximum amplitude at one end or the other of the cycle. The barrel swings from a maximum angle to the axis, through a parrallel position, to an angle opposite to the first. So the real question you're asking is ...Do these maximum angles get larger, or do they get smaller when you add a tuner?

The angles get smaller when you add a tuner.

 

[Lynn]

Other than the position - where Bill moved it to the muzzle - yes it is. It still shows the "flat kink" that cannot be formed.

Vibe
The statement "other than the position" doesn't sound very engineering accurate in a post were everyone is so critical about terminology.

Flatter is important - "wider" is a side effect of that where "flat" is all amplitude less than X, but the node itself is still just a single point.

Vibe
The node is still a single point but on both sides of the single point the normal arc is now flatter and wider.If you re-read Bills posts he said it is a arc with a very large radius.Flatter and wider seems to resemble very large arc.


Bills claim of a tuner requireing no further adjustment has yet to be substantiated by reports to this forum -

Vibe
If look at the posts on the centerfire forum and the posts on the rimfire forum or even the posts by Beau there are plenty of shooters saying once the tuner is set you never touch it again.This is not a new claim but one that has been around for quite some time now.


Lynn, as far as moving an anti-node to the muzzle...I don't think that that would be of any real benefit. Though the Browning Boss method was to modify the timing of the "beyond the node" swing to the point that the bullet exits on the end of the upward swing at the "stopped" point. With the slowest bullets in the SD exiting at the true stopped point and faster ones slightly lower - resulting in a self closing group at a given range.

Vibe
I think you just said exactly what Bill has been saying.The "Stopped Point" is then made wider and flatter with the additional weight of the tuner causing the Parallel node.
If you plot a section of barrel from zero degrees to 10 degrees from the receiver and you plot a second plot from 260 degrees to 270 degrees they would look parallel to each other and one would be at the muzzle.

 

[Beau]

My computer is often on and logged in while I go to bed during the day. Be careful with assumptions. I've answered as best I could. LOL. I'm stiff, There's a pot calling the kettle black.
Watch again the animation of the Clamped-Free (Cantilever Beam) at
http://paws.kettering.edu/~drussell/Demos/Flexural/bending.html
If you can find where the shape EVER looks like the 2nd drawing here
http://benchrest.com/forums/attachment.php?attachmentid=8434&d=1251769026
Which is exactly what Bill claimed to be happening - and demonstrate it here. I'm sure we would all be grateful.



You are very skilled at reading in just exactly what you wish to see then. And even then you must have had to put quite some effort into it.

Vibe,

I just got in from Missouri so I'm a little too tired to joust with you tonight. Just remember if everybody agrees, discussion will stop. 'Cause everybody is happy.

I think your picture #2 is showing the clamped barrel or rod as it may be, but remember I'm tired. If so, the top one is what Bill demonstrates. I'll look at it closer tomorrow.

The Parallel Node is like saying the blowing wind. If it's not blowing, it's not wind, but the adjective doesn't make it wrong. Even Pacecil said the node stayed parallel to the axis.

 

[Lynn]

Pacecil
If you look at your pictures they show us more than 180 degrees and less than 270 degrees or 3/4 wave length.The nodes are at 0 degrees 180 degrees and 360 degrees along our wave with the anti-nodes being at 90 degrees and 270 degrees.The wave itself looks more like a spiral staircase and the muzzle as Varmint Al has pointed out and it makes a sweep and does not cut a straight plane.
If you plot a 10 degree sectrion of the barrel from the receiver or 0 degrees to 10 degrees forward of the muzzle you would get what resembles a straight line.Our half wave is roughly 21 inches long with a peak to peak maximum amplitude of 0.004 inches or 0.002 inches to a single point located exactly at the anti-node or 90 degrees.
If you plot a second plot using (X,Y)co-ordinates from 260 degrees to 270 degrees or just before the 3/4 wavelength anti-node to the anti-node and you superimposed it over your first plot you get instant "parallel node".
It isn't a single point but if you plot it out it fits Bills description to a tee.
Waterboy

 

[Beau]

Beau, varmit Al, one last try. if you time or tune a rifle with one velocity of ammo and that ammo is outstanding, with a variaton of 5 fps is the rifle really tuned? nipper just made a point that a lot of shooters run into. a rifle is bought and with that rifle is sometimes given tuned ammo. once that ammo is used then the rifle goes to pot. it takes me several hours and a bunch of ammo to tune a rifle, if it can be done faster and with less ammo I would like to know. and I don't think a person has to have a phd to be at the top of their feild. I think Bill Calfee, Harrry Deenen and others are head and shoulders above most and would like to know what they see that most of us don't. this stuff with nodes goes right over my head, as I'm sure it does to a lot of us. most feel a tuner helps good ammo and just want to be knowlageable not to mess it up.

I think understanding the nodes is for development, not actual use. One last try, once the rifle is tuned, it's tuned if you did it right, you should not have to change it for various velocities. If you do, you're wasting your time and probably making your gun shoot worse. What nipper said, if I got it right was that his gunsmith told him he should never have to move the tuner over five clicks in either direction. Weigh the movable part of the tuner, determine how much mass you're actually moving and how far and tell me what that would do. Or I can tell you. Nothing noticeable.

 

[Vibe]

Other than the position - where Bill moved it to the muzzle - yes it is. It still shows the "flat kink" that cannot be formed.

Vibe
The statement "other than the position" doesn't sound very engineering accurate in a post were everyone is so critical about terminology.

And yet it is accuate. The "Image #2" is EXACTLY what Bull claimed to be seeing - seems it is an almost exact duplicate of his drawing. He just wanted to move the "flat kinked spot" to the muzzle.

Flatter is important - "wider" is a side effect of that where "flat" is all amplitude less than X, but the node itself is still just a single point.

Vibe
The node is still a single point but on both sides of the single point the normal arc is now flatter and wider.If you re-read Bills posts he said it is a arc with a very large radius.Flatter and wider seems to resemble very large arc.

Lynn - your appologetic interpretation of what Bill is trying to say has never really sounded like what Bill was sayiing. I think you are closer. But "flatter" is not "flat" and a node is still only one point wide, and that portion of the "arc" is still not parallel to anything.

Bills claim of a tuner requireing no further adjustment has yet to be substantiated by reports to this forum -

Vibe
If look at the posts on the centerfire forum and the posts on the rimfire forum or even the posts by Beau there are plenty of shooters saying once the tuner is set you never touch it again.This is not a new claim but one that has been around for quite some time now.

And yet all of those posters are STILL speaking of making adjustments - completely defeating any claims that they "never touch them again".

Lynn, as far as moving an anti-node to the muzzle...I don't think that that would be of any real benefit. Though the Browning Boss method was to modify the timing of the "beyond the node" swing to the point that the bullet exits on the end of the upward swing at the "stopped" point. With the slowest bullets in the SD exiting at the true stopped point and faster ones slightly lower - resulting in a self closing group at a given range.

Vibe
I think you just said exactly what Bill has been saying.The "Stopped Point" is then made wider and flatter with the additional weight of the tuner causing the Parallel node.
If you plot a section of barrel from zero degrees to 10 degrees from the receiver and you plot a second plot from 260 degrees to 270 degrees they would look parallel to each other and one would be at the muzzle.

.
This having to re-edit the HTML is fun...not.
And no they would not be parallel - one will have a positive slope and the other will have a negitive slope (or vice versa). They might be "close" to being "parallel" - but unless you are going to start accepting 9s as 10s or Xs because they were "close" to being in the bullseye, you don't really want to continue using that excuse. Because you'd eventually have to start accepting 8s and then 7s.

No. Bills claim was that the "stopped point" would be "stopped" regardless of the speed of the ammo - What I'm describing is only stopped for a relatively narrow range of speeds, and will DEFINATELY need to be "readjusted" for any particular speed range.

 

[Vibe]

One last try, once the rifle is tuned, it's tuned if you did it right, you should not have to change it for various velocities. If you do, you're wasting your time and probably making your gun shoot worse. What nipper said, if I got it right was that his gunsmith told him he should never have to move the tuner over five clicks in either direction.

Never having to move the tuner is not the same as never having to move the tuner over five clicks in either direction - Which is it?

Weigh the movable part of the tuner, determine how much mass you're actually moving and how far and tell me what that would do. Or I can tell you. Nothing noticeable.

If you can tell that it improves or degrades the accuracy AT ALL then it is no longer "Nothing noticeable", but is instead VERY noticeable. That seems to be one of the problems of this discussion - sinply trying to discount those observations which do not seem to fit the preconceived conclusion.

 

[martin hammond]

I re-read nippers post, I do not beleive his riflemaker tuned his rifle. I should be getting another rifle back from a bedding job, at that time I will write down how I tune. right now I write notes on the usbr targets shot while tuning. when my rifles are tuned you can interchange on the same target good lots of ammo and not miss a beat. Tom C came up and shot with me a month ago, he was shooting a psl target with my 40x. it has a Stith stock, Sitman bedding a jewel trigger and a Harrell's tuner with 5oz of weights. I timed it using 3 seperate speeds of ammo. Tom was shooting eley black box 1069 speed. after target 18 he used the last of it, I didn't see any setting on my bench, and said to him here use this it will go in the same hole. I handed him an open box of team 1056 speed. his reaction was no way, I said shoot it and see. he did not miss a beat on that target. Beau, I know my rifles are tuned and timed right, unless Bill Calfee is pounding smoke and tuned the rifle without you knowing it I am not convinced a rifle can be timed properly with a few shots. if it can be done me and a lot of others would love to know how.