Plunger button

PLEASE HELP TO FUND ARCHERY INTERCHANGE

A16KSB

Member
Hi All,
If an arrow is properly spined to a particular bow, is a plunger button required?
If the arrow bends around the riser and doesn't make contact, what is the purpose of a plunger button?
I know some use it for windage, if so haven't you changed the dynamic spine of the arrow?
TIA
 

Rik

Supporter
Supporter
The plunger doesn't affect the spine...? A properly spined arrow is the starting point *before* you set up a plunger. Trying to use a plunger to compensate for an incorrect spine is kind of pointless.

If you don't use a plunger, then presumably you would use some other sort of contact point? So basically doing a set up with a stiff plunger
 

A16KSB

Member
The plunger doesn't affect the spine...? A properly spined arrow is the starting point *before* you set up a plunger. Trying to use a plunger to compensate for an incorrect spine is kind of pointless.

If you don't use a plunger, then presumably you would use some other sort of contact point? So basically doing a set up with a stiff plunger
I'm a bit confused, Yes I agree t hat the plunger doesn't affect the spine, however doesn't it affect the dynamic spine if the arrow actually touches it as it leaves the string going down range.
I think what I trying to ask was if an arrow bends correctly, and doesn't touch anything on it's travels, then why is a plunger needed?
 

geoffretired

Supporter
Supporter
A plunger button allows different thicknesses of arrow shaft to be aligned with a slight off centre position. A fat arrow and a thin arrow without a button, would align differently and getting that right for the arrow and the bow would require packing out for the thinner shaft.
I think the stiffness of the button is important. It is different from shooting off a rigid contact point. Ithink James Park did a lot of work with this aspect and found the rigid button caused issues. A solid contact for the arrow would have similar effects to a rigid button.
Plus, a button provides an initial direction for the launch of the arrow. Changing the position of the button can change the direction of the arrow flight. That allows for the arrow to fly directly ahead so the sight windage won't need to be adjusted as the sight is adjusted for different distances are shot.
 

Timid Toad

Moderator
Staff member
Supporter
Fonz Awardee
Ironman
The button compensates for *you*. Your dodgy looses,
A trad archer shoots off the shelf and no button, only a pad to move the arrow across centreshot. They still have to have the right spine but spine steps are quite large and the only choice for fine tuning is centreshot or a longer or shorter shaft (no clicker to worry about either) They frequently have to iron out contact with the bow and have no compensation for an iffy loose.
So the button allows you to fine tune within your correct spine choice. And helps mitigate for your poor looses.

It clearly makes a difference because as soon as it was invented, everyone got one and started shooting it in international competition. But we've forgotten what it does and what its limitations are.
 

A16KSB

Member
The button compensates for *you*. Your dodgy looses,
A trad archer shoots off the shelf and no button, only a pad to move the arrow across centreshot. They still have to have the right spine but spine steps are quite large and the only choice for fine tuning is centreshot or a longer or shorter shaft (no clicker to worry about either) They frequently have to iron out contact with the bow and have no compensation for an iffy loose.
So the button allows you to fine tune within your correct spine choice. And helps mitigate for your poor looses.

It clearly makes a difference because as soon as it was invented, everyone got one and started shooting it in international competition. But we've forgotten what it does and what its limitations are.
Thanks, that sort of agrees with what I was trying to say. In a perfect world , i.e. perfect release and perfectly matched shaft a button with a spring would not be required as the arrow shaft would bend the correct amount to avoid any unnecessary contact, but something would be needed for it to initially rest on and do the initial guidance. My thinking is that whilst the arrow is in contact with the button and it is weak a stronger spring is used to reduce the flex, and when a stiff arrow is used a weaker spring is used to absorb some of the flex, however I'm happy to be corrected
So my thinking is that if an archer uses the plunger to adjust windage they have changed how much of the flex is being absorbed, and at the same time changed the centre shot.
PS I shoot trad off of the shelf and agree totally
 

Rik

Supporter
Supporter
Thanks, that sort of agrees with what I was trying to say. In a perfect world , i.e. perfect release and perfectly matched shaft a button with a spring would not be required as the arrow shaft would bend the correct amount to avoid any unnecessary contact, but something would be needed for it to initially rest on and do the initial guidance. My thinking is that whilst the arrow is in contact with the button and it is weak a stronger spring is used to reduce the flex, and when a stiff arrow is used a weaker spring is used to absorb some of the flex, however I'm happy to be corrected
So my thinking is that if an archer uses the plunger to adjust windage they have changed how much of the flex is being absorbed, and at the same time changed the centre shot.
PS I shoot trad off of the shelf and agree totally
Ah, yes. People misunderstand the whole "flex thing". That's not why spine is used for matching. So long as the shaft bends a bit, how much it bends is nearly irrelevant (so long as it's not extreme). But the bending frequency tends to go with stiffness, and when the shaft bends (the point in the cycle it's at when it passes the bow) therefore goes with stiffness. It's not how much it bends, but when.
Thing is, you can't change that frequency with the button.
You can alter the starting point of the cycle, and speed at which the shaft passes the bow, with draw weight and BH. String weight and shaft weight (point or back) also have some effect on that. You tend to see these thing referred to as "dynamic spine" but it's really just fiddling with the matching of the system, nothing to do with spine.
 

Whitehart

Well-known member
The button sets the launch angle of the arrow, the spring tension means the part of the arrow in contact for that short period keeps the arrow pointing in the right direction as the arrow initially starts to bend and offers a bit of smoothing out that a hard surface cannot do. Whilst it cannot change arrow spine, dynamic or otherwise it gives the archer the flexibility to make easy adjustments to the angle the arrow leaves the bow.
 

jerryRTD

Well-known member
Thanks, that sort of agrees with what I was trying to say. In a perfect world , i.e. perfect release and perfectly matched shaft a button with a spring would not be required as the arrow shaft would bend the correct amount to avoid any unnecessary contact, but something would be needed for it to initially rest on and do the initial guidance. My thinking is that whilst the arrow is in contact with the button and it is weak a stronger spring is used to reduce the flex, and when a stiff arrow is used a weaker spring is used to absorb some of the flex, however I'm happy to be corrected
So my thinking is that if an archer uses the plunger to adjust windage they have changed how much of the flex is being absorbed, and at the same time changed the centre shot.
PS I shoot trad off of the shelf and agree totally
You have to select the right spring to go in the button . get that wrong and you will find that the plunger will ;bottom out. that can give strange random errors.
I am old enough to remember when bow did not come with a bushing for a button, setting up was knife edged . .now you can tweak the button an get the nodes aligned.
 
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