Recurve Equipment tuning

8/10/2019 Recurve Equipment tuning

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Intermediate

Level

RECURVE BOW

EQUIPMENT TUNING

Module

FITA

CoachsManual


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Module

RECURVE BOW EQUIPMENT TUNING

FITA Coaching ManualIntermediate Level

Introduction, to tuning competitive recurve bows

Tere is no doub ha he bow you choose is an impor-

an consideraion, bu even more imporan han hebow are he arrows you choose. In he early days o com-

peiive archery, i was no uncommon or an archer o

pay a weeks salary or a dozen op qualiy ooed cedar

arrows. Remember, i is no he bow scoring he poins in

he arge; i is your arrow shafs. Successul bow uning

and accurae shooing can only be achieved by using ar-

row shafs ha are properly spined o your bow and ones

ha are consisen in heir spine, weigh and sraighness.

Follow he many available spine chars or compuer pro-

grams on he marke o selec he arrow size recommend-

ed or your draw lengh and bow poundage. Remember o

read all o he inormaion provided on he proper use or

he char oo. Te rue verificaion ha you have seleced

he correc spine will be deermined during he uning

process. Problems caused by improperly spined arrow

shafs will become eviden during uning. Beore uning,

be sure ha all arrows are sraigh, properly fleched, and

have perecly aligned nocks.

Shooing Technique

Your shooing echnique can have a large influence over

he dynamic spine value o your arrow. wo archers

shooing he exac same bow, same poundage and he

same arrow lengh may no necessarily shoo he same

arrow size. Usually, he archer who has beter line, (see

shooing orm chaper or deails on body alignmen) will

shoo a ligher (weaker) spined arrow han an archer who

has poor skeleal alignmen. Tis is because he archer

wih good alignmen creaes less side movemen o hesring on release resuling in less column loading o he

arrow shaf.

Insall All AccessoriesBeore saring he bow uning process, be sure o insall

every piece o equipmen on your bow ha you inendo use during shooing. Tis includes he correc bow-

sring and all atachmens o he bow sring, bow sigh,

sabilizers, arrow res, cushion plunger, couner weighs

ec. Choose all personal iems as well, like your ab, ches

proecor and any hing else you use when shooing. For

example, simply changing a sabilizer can have an enor-

mous effec on he une o your bow. Any adjusmens

made o he bow or changes in bow componens can and

usually will affec he une.

Once he equipmen is ully assembled, he nex phasein he process o achieving well uned equipmen is good

preliminary seup. I he iniial seup is done properly, he

uning process can be accomplished wih litle effor. By

ollowing he bow seup guidelines in he iniial prepara-

ion o your equipmen, you can eliminae mos or all o

he possible uning problems ha can make he process

ime consuming and unsuccessul.

Adjusmens made o he bow, changes in bow com-

ponens, or aleraions in shooing orm can affec he

une or your equipmen. Remember, you and your equip-

men share a unique relaionship and are oally ine-

graed. Any change o eiher will produce varying resuls.

During he uning process, i is vially imporan ha you

change only one variable a a ime. Oherwise, i is very

difficul o deermine wha adjusmen caused any group-

ing changes. I, afer rying all o he uning adjusmens

oulined in his chaper, your arrows sill do no fly rue, i

may be necessary o change your arrow size o a siffer or

weaker shaf and reune.Arrows in fligh spin, vibrae and oscillae in he hori-

zonal plane, and can oscillae in he verical plane wih a

misplaced nocking poin. Proper bow-se up and uning

will help minimize he orces on he arrow and help he

archer o achieve opimum perormance. Unorunaely,

here are many heories on arrow fligh and vigorous

mahemaical reamen o hese is a bi hard or mos

non-engineers o undersand. Te botom line hough, is

ha all archers can recognize he arrow fligh problems

and make appropriae correcions. Figures showing heroaion o arrows in he horizonal and verical panes are

shown below.


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Recurve Bow Equipment Tuning

In his secion on recurve bow uning i will be necessary

o discuss a number o differen ypes o risers since he

available adjusmen eaures differ in each case.

Te ypes o risers are:

Simple wooden sel or ake down bows.

Meal risers wih cushion plungers bu no weigh ad-

jusmen capabiliy.

Meal risers wih cushion plungers & weigh adjus-

men bu no limb pocke adjusmen capabiliy.

Olympic Recurve risers (weigh adjusable, cushion

plunger and limb alignmen capabiliy).

Forces acing on he arrow

For he purpose o simpliciy, all discussions rom his

poin on will be made in reerence o a righ handed arch-

er shooing a righ handed bow. I he archer is shooing

a lef handed bow he same commens apply bu in re-

verse.As he archer releases he arrow, he sring moves hori-

zonally o he lef (acing he arge) moving he nock o

he lef. As he sring sars o move orward moving he

nock end o he arrow, he poin end resiss his move and

his resuls in he arrow bending oward he bow. When

he arrow complees his iniial bend, he sring and nock

move back oward cenre and hen o he righ o cenre.

A his momen he ron secion o he arrow pushes

agains he sigh window ace or a cushion plunger i fi-

ed. All o his acion occurs in a racion o a second inhe firs several inches o orward ravel o he arrow. In

he nex horizonal bending sequence as he arrow leaves

he bow ace and arrow res he arrow is in a nearly ree

mode, only being held by he bowsring during his sec-

ond hal cycle. A he end o his complee cycle (bending

in oward hen bending away rom he bow), he arrow

nock disengages rom he bowsring sending he arrow

on is way o he arge. Tese acions o he arrow are

ermed Archers Paradox and are he cause o arrow vi-

braion and arrow horizonal oscillaion.

Figure .

Te drawing shows he posi-

ion o he fingers a ull draw

and a he ime o he release,

he pah o he sring and he

iniial bending o he arrow as

he sring propels i

oward he arge.

Figure .

Figure .


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FITA Coaching Manual Intermediate Level

Fron o Cenre Balance ()Arrows fly more accuraely and wih more sabiliy i hey

are ron heavy. Tis is paricularly rue o shooing in

he wind. Te erm used o describe he locaion o he

arrows balance poin is . I is defined as how ar he

balance poin is orward o he arrows mid poin and isexpressed as a percenage o oal arrow lengh.

FOCL/2 B

L=

100

Where: L is arrow lengh

B is lengh rom balance poin o ron o arrow

For oudoor shooing, many archers assemble heir ar-

rows wih quie a high Fron o Cenre balance poin,

hough his depends on he ype o arrows being assem-bled, he lengh o arrow and he poundage/speed o he

bow. Consideraion mus be given o acquiring a good

sigh mark a he longes disance being sho. For indoor

shooing a high Fron o Cenre balance poin may be

used bu be aware ha going oo high may be derimenal

o he perormance required.

Tuning and Bow Set-up

uning and bow se-up are he processes by which he

archer can adjus he bow and arrow so ha he fligh

problems caused by he Archers Paradox can be mini-

mized and good arrow grouping can be achieved. Te

uning process is a whole sysem process wherein he

bow, all o is atachmens, he arrow and he archer can

be brough ino harmony. Any change, simple as i may

seem, can affec bow une. Somehing as simple as a new

se o finger abs can have a dramaic affec on a finely

uned bow. Te uning process is a discipline wherein he

shooing characerisics o he arrow are modified o op-imize perormance. Bow se-up is a series o equipmen

based asks whereas uning is required o accommodae

he sho variaions caused by he archer. Properly made,

mached arrows will group ighly when sho ou o a

shooing machine however an archer shooing he same

equipmen will experience sho variaion.

Bow Se-upInsall All Accessories

Beore saring he bow uning process, be sure o insallevery piece o equipmen on your bow ha you inend

o use during shooing. Tis includes he correc bow-

sring and all atachmens o he bow sring, bow sigh,

sabilizers, arrow res, cushion plunger, couner weighs

ec. Choose all personal iems as well as, your ab, ches

proecor and anyhing else you use when shooing. For

example, simply changing a sabilizer can have an enor-

mous effec on he une o your bow.

Once he equipmen is ully assembled, he nex phasein he process o achieving well uned equipmen is a

good preliminary seup. I he iniial/preliminary seup is

done properly, he uning process can be accomplished

wih litle effor. By ollowing hese bow seup guidelines

in he iniial preparaion o your equipmen, you can

eliminae many o he possible uning problems ha can

make he process ime consuming and unsuccessul. Ad-

jusmens made o he bow, changes in bow componens,

or aleraions in shooing orm can affec he une o your

equipmen. Remember, you and your equipmen share aunique relaionship and are oally inegraed. Any change

o eiher will produce varying resuls. During he uning

process, i is vially imporan ha you change only one

variable a a ime. Oherwise, i is very difficul o deer-

mine wha adjusmen caused any grouping change.

Nock-o-Bowsring FiTe orce necessary o separae he nock rom he bow-

sring serving is very criical, especially on ligh draw-

weigh bows ( lbs. and under). Nock ension should

be igh enough so he arrow can easily suppor is own

weigh when he arrow is hung rom he bowsring in a

horizonal posiion bu weak enough so ha he arrow

will all i he sring is apped sharply wih your finger (see

figure below). In order o ge he proper nock fi you

can use eiher a large or small groove nock or adjus he

serving diameer by choosing differen serving hread di-

ameers. I he sring ension is oo loose, here is a danger

o he nock slipping off he sring a ull draw causing adry fire. Tis could no only damage he bow, bu can also

cause a serious bruise o he archers bow arm.

Figure .


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Insall he Arrow ResA wide variey o arrow ress is available o he archer.

Tey all have one hing in common hey mus be fited

so ha he angle o he arm assiss he arrow o say on

he res and does no allow he arrow o slide off he res

beore he sho is made (figure ). Ress range rom hesimple sick on plasic variey o adjusable meal arms

which move away rom he arrow as i is sho. Te high

speed films described earlier show ha he main uncion

o he res is o suppor he arrow during draw and dur-

ing he iniial movemen o he arrow orward. As archers

paradox akes place he arrow lifs off he res. Te res

needs o be adjused so ha he cenre o he arrow is con-

acing he cenre o he cushion plunger (Figure ), and

he suppor arm mus be adjused so ha i is no visible

pas he ouside o he arrow shaf when observed roman overhead view (figure ).

Figure

Angle of arrow rest arm &

Plunger alignment with the arrow.

Figure

Arrow Rest Arm.

Insall he Nocking Poin

Tis is a common sep wih all recurve bows. Insall a

moveable nocking poin on he bowsring. Clamp-on

ypes are saisacory and easy o insall bu affec arrow

fligh. We sugges ha you use a ie on nocking poin.

Incorrect Incorrect Correct

Incorrect Correct

Iniial Nocking Poin Posiion.

Figure .

Iniially, posiion he nocking poin on he bowsring

abou mm (/ inch) above square (Figure ).Te nock o he arrow will be placed above his nock-

ing poin. Afer his nocking poin is in place ie a nd

nocking above he firs one wih sufficien room beween

he wo poins so ha a nock will easily fi beween. Tis

will preven an arrow rom sliding down he sring during

shooing.

Tying on a Nocking Poin

Te ied on nocking poin is made wih a shor piece, -

cm (-) o he same serving maerial used o serve

he sring. Begin by ying an overhand kno around he

bowsring serving. Nex ake he ree ends, urn hem un-

der he bowsring and ighen he kno. Alernae knos

above and below he sring unil you have ied - knos.

End he nocking poin by ying he final kno in a square

kno. Cu off he loose ends o abou mm (/) lengh

and hea hem wih a mach or ligher. Tey will burn back

o he main kno and use he fibres o he sring you used

or he nocking poin. Tis nocking poin can be movedup or down he serving by wising i since i acs like a

nu and he served sring as he screw. Tis is he reason

you should use he same maerial as you used or he serv-

ing since you ge a perec hread mach.

90

Have the top of the

boom nock ing point

approximately 5

millimetres above

square.


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o find he limb cenre or a recurve bows, place a piece

o masking ape across he inside o each limb near helimb pockes). Measure he widh o each limb and make

a small verical mark on he ape in he exac cenre o

each limb abou cm ( in.) rom he limb pockes o he

riser. Be very accurae when doing his and measure sev-

eral imes o know you have locaed he exac cenre o

each limb. Tis mark will be used or arrow cenering. I

may be easier o see i he sring is cenralised i wo lines

are marked on he limb, insead o one, which are mil-

limeres apar. Wih one line his line would be hidden

behind he sring when alignmen is being checked. More

convenienly use commercially available Limb Line

Gauges available rom mos good archery shops.

Afer you mark he limb cenres on he ape or insall

he Limb Line Gauges, sand back and atemp o sigh

align he sring wih he marks. I you canno do his

you will need o eiher average he alignmen or i your

bow has he capabiliy o adjusing limb alignmen, do so.

Tis is mos easily accomplished by placing one marked

ape where he limb comes ou o he riser and one apea cm (in.) rom he bow ip on boh limbs (or use spe-

cific gauges). You can hen check he alignmen o he

marks o assess i he limbs are properly aligned (Figure

). Sand back and sigh hrough he sring o see i i

covers all marks. I no, make limb alignmen adjus-

mens as required.

Some bows may have a slighly ben riser or crooked

limbs. In his case, since he sring will no perecly bisec

he cenre o boh limbs a he same ime, you will need

o compensae or average he sring posiion or he slighimbalance. Tis does no mean he bow will no shoo ac-

curaely, i simply means you need o compensae or his

siuaion.

Figure .

Cenering he Arrow: Adjusing he Arrows Lef/Righ Posiion

Te objecive o arrow cenering is o have he arrow leave

he bow in he same verical plane as he average sring

orce moves. o accomplish his, he archer should sand

behind he bow which is held in a verical posiion and

sigh orward hrough he sring which is aligned wih

he bow cenreline. See Figure or proper arrow cener-

ing. Te arrow should be moved in or ou rom he bow

so ha he poin appears jus o he lef o he sring. For

bows equipped wih a cushion plunger his can be accom-

plished by urning i in or ou. Bows wihou a cushion

plunger can be buil ou rom he bow ace i he arrow

mus be moved lef however i he poin is already ouside

o he sring i is impossible o move he poin urher

righ because o he riser.

Figure . Figure .


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Align he Bow Sigh Pin or Aperure:Se he sigh pin or aperure on your bow sigh direcly

over he sring when i is aligned down he cenre o he

bow, see figure . Te one objec o he uning process

which ollows is o selec he correc arrow and bow ad-

jusmen so ha he arrow is aimed and moves orwardin he orce plane o he moving bowsring as he arrow

is sho. You will noice a number o archers whose sigh

is eiher ouside or inside he sring. Tis is because hey

have uned heir bows o an improper iniial arrow align-

men or are using arrows eiher oo siff or oo weak or

heir se-up.

Noes on Clickers

Tere are several hings o be aware o when using

a clicker. Be sure ha he arrow is well supporedon he res and no held in place only by he ension

o he clicker. Draw he bow a ew imes wihou he

clicker o make sure he arrow can be drawn and le

down wihou he arrow alling off he arrow res. Te

clicker ension and angle are imporan oo. Te clicker

should no be so siff ha i acually moves he cush-

ion plunger in or places a downward pressure on he

arrow. o es his, sand in ron o a arge (jus in case

you have an unexpeced loose o he sring ) and draw

he arrow hrough he clicker as i you were going o

shoo, bu do no shoo he arrow. Raher, wach only

he arrow on he res o deec any movemen o he

arrow a he momen he arrow is pulled hrough he

clicker and he clicker makes conac wih he riser. I

here is any movemen o he arrow, eiher a bounce on

he arrow res or he arrow moves ou due o cushion

plunger acivaion, you need o correc his. Tere mus

no be any observable movemen o he arrow when he

clicker is acivaed.

Se he Cushion Plunger PressureI he bow is equipped wih a cushion plunger, se he

plunger ension o o he ension o he lighes

spring. Te seting will change laer on in he uning

process. I you don use a cushion plunger, your uning

adjusmens are going o be ar more limied in he uning

process.

Seting Iniial Brace HeighSar wih he brace heigh a he lower end o he manu-

acurers recommendaion range or use he ollowing

char.

(. cm. cm)

(. cm. cm)

(. cm. cm)

(. cm. cm)

Te manuacurer recommended brace heigh seting isonly a guideline. Changing he brace heigh o a slighly

higher or lower posiion can affec arrow fligh and group-

ing. Te proper seting or bes arrow grouping perorm-

ance will be deermined laer in he uning secion.

Tilleriller is he erm used o describe he relaive bending

o boh bow limbs. I is assessed by measuring he per-

pendicular disance beween he bow sring and limb a

he end o he limb pockes. By convenion, he readingsare made in reerence o he upper limb reading. Hence, a

posiive iller is one where he disance rom he sring o

he upper limb a he limb pocke (a) is greaer han he

disance or he lower limb (b), see figure .

Figure .

A negaive iller is where he lower reading is greaer. For

many years i was acceped ha a posiive iller was re-

quired since he archer was grasping he sring above he

bow cenre and held he sring wih one finger above andwo below he arrow nock and was a resul o he pres-

sure poin o he hand on he riser. Recenly mos archers

adjus he iller o zero or leave i where he manuacurer

(a)

(b)


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made he limbs. Te later is probably a bad idea since

some limb pairs as purchased can have an iniial iller as

high as mm (/ inch).

Some archers and coaches eel ha i is necessary o

adjus he iller o keep he sigh seady on he arge. o

do his, make very small adjusmens o iller (less hanmm a a ime) and see how your sigh patern is affeced.

Anoher indicaion ha he iller is correc is he bow

hand will eel like one concenraed poin raher han

a sligh rocking eeling in he hand. On he oher hand,

many archers and coaches se he iller a zero and leave

i here.

One note o caution.Changing iller moves he loca-

ion o he nocking poin and is posiion mus be read-

jused afer each change in iller. Increasing iller moves

he nocking poin down and reducing iller moves henocking poin up in relaion o he arrow res. Te nock-

ing poin mus be relocaed afer each iller change. Do

no use iller adjusmens as a means o moving he nock-

ing poin since changes in iller affec how he bow per-

orms.

Seting he Final Brace HeighAll bows are differen, even bows o he same make and

model can have small variaions in limb lengh. Tere-

ore, i is imporan o locae a brace heigh ha fis your

paricular bow and shooing syle. Shoo a ew arrows a

he suggesed beginning brace heigh, hen unsring he

bow, add - wiss o he bowsring and shoo again.

Coninue his process unil he bow eels smoohes and

quiees when shooing.

I he bowsring is oo shor o allow a brace heigh

a he lower seting, use a slighly longer sring. I he

sring is oo long o allow a higher brace heigh (and

sars o kno-up rom oo many wiss), ry a slighlyshorer bowsring. Tere are many cusom bowsring

makers who produce srings o your exac specificaions

including lengh, ype o maerial, number o srands in

he sring and ype and colour o serving. I here are

a lo o wiss in he sring, i will ake ewer wiss o

increase brace heigh han i here are ew wiss in he

sring. Also, i is no recommended o have oo many

wiss in he sring or i will ac more like a spring han

a sring. Bu, here should be enough wiss o make i

look like a nice round cable.

TuningGeneral

Afer he bow is se-up as oulined above, he archer may

begin he uning process.

As described earlier, he finger release causes he arrow

o vibrae and o oscillae in he horizonal plane. Arrowfligh appears o ollow a snake like movemen patern.

Tese movemens o he arrow are caused by archers

paradox where he sring moves around he fingers on re-

lease. Te goal o uning is o selec and adjus an arrows

fligh characerisics o minimize hese effecs and o ge

he arrow o leave he bow wih zero deg. angular roaion.

I will sill be vibraing bu hese vibraions are dampened

ou in he firs -m o fligh by drag orces on he ar-

row shaf. uning will also minimize he archers shooing

orm variabiliy and help him ge smaller groups.Your shooing echnique can have a large influence

over he dynamic properies o your arrow. wo archers

shooing he exac same bow, same poundage and he

same arrow lengh may no necessarily require he same

arrow size. Usually, he archer who has beter line, (see

shooing orm chaper or deails on body alignmen)

will shoo a ligher (weaker) spined arrow han an arch-

er who has poor skeleal alignmen. Tis is because he

archer wih good alignmen creaes less side movemen

o he sring on release resuling in less iniial bending o

he arrow shaf.

As will be shown shorly, here are a number o iner-

acing uning variables which can be employed o bes

une your sysem. Tere is no one unique se-up o hese

variables o achieve he desired minimum group size you

are seeking. In ac, i is normal o be able o achieve a

good bow une wih more han one siffness grade o ar-

row. Wih his in mind, many people preer o une heir

bow wih a siffer arrow because i is believed o be moreorgiving. Forgiving in his sense is ha he arrow will

readily accommodae variaions in he archers shooing

echnique.

uning is bes carried ou as a saisical process. Each

arrow should be numbered o see i here is any fligh

bias, good or bad, associaed wih ha arrow. Te archer

should shoo more han he minimum o shos o charac-

erize heir arrow fligh. For example, i he mehod calls

or shooing or arrows rom a given disance i is sug-

gesed ha he archer shoos a leas shos. Te archercan hen eliminae or discoun any obvious poor shos

rom consideraion.


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Tuning MehodsTere are a number o uning mehods used oday bu

mos are eiher lenghy or inaccurae. Many depend on

he use o bare shafs as a primary reerence or fleched

arrow fligh. Bare shafs do no have good fligh charac-

erisics unless he bow is airly well uned. Some o heuning mehods used and commens on hem are:

Paper Tuning:Primarily a compound bow wih release

aid uning mehod. Because o archers paradox and he

resulan arrow fligh his mehod has litle validiy or

people using heir fingers o release he arrow.

Walk Back Tuning:Involves shooing arrows a disanc-

es o - meres wihou moving he sigh and aiming

a he same poin and hen analyzing he hi patern. Tismehod is no sufficienly sensiive in uning carbon/alu-

minium shafs bu is said o work saisacorily wih alu-

minium arrows.

Short Distance Tuning: Tis mehod involves shoo-

ing fleched arrows a a verical and a horizonal line. I is

used mainly o veriy nocking poin and cushion plunger

in/ou seting.

Bare Shaf Planing Test: Tis mehod compares he

grouping patern o bare and fleched shafs. I produces

good resuls bu shooing bare shafs beore a good une

is achieved may be rusraing or he archer.

Fletched Arrow Group Tuning:Tis mehod has been

used or many years and does no have a name. I is prob-

ably he simples mehod ha yields he bes resuls o

oher uning mehods and is highly recommended. I can

also involve shooing bare shafs bu no beore a basicune is esablished.

Tuning ToolsIn all o he uning mehods a number o variables can

be used o adjus he shooing characerisics o an arrow.

All o he ollowing deal wih he arrows dynamic spine

which is he amoun o iniial bend he arrow undergoes

as he sring is released. I is how weak or siff he arrow is

as i is sho. Mos requenly his characerisic is reerred

o as he arrows spine. Unorunaely, arrow manuacur-ers also use he same erm, spine, o describe he stiff-

nesso heir shafs. Tese wo spines are really static

spine or he siffness o he arrow a res as measured by

a spine or deflecion eser and dynamic spine which is

he bending characerisics o an arrow as i is sho rom

he bow.

Facors Affecing Dynamic Spine

Dynamic spine is affeced by a number o acors, mos owhich can be adjused o improve arrow fligh.

Adjustments to increase dynamic spine, making the ar-

row shoot stiffer

decrease poin weigh

add weigh o he nock end o he arrow

shoren he shaf

decrease bow weigh

decrease brace heigh. Be careul here as his gives a

longer power sroke hus makes he arrow seem weak-er.

increase sring weigh

change arrows o a siffer shaf size, i.e., lower saic

spine value.

Adjustments to decrease dynamic spine, making the arrow

shoot weaker or bend more

increase poin weigh

lenghen he shaf

increase bow weigh

increase brace heigh be careul here as his gives a

shorer power sroke hus makes he arrow seem siff-

er.

decrease sring weigh

change arrows o a weaker shaf size, i.e., increase sa-

ic spine value.

Tere are some limiaions in applying hese changes. Te

poin weighs are deermined by wha he archer can pur-chase. I he archer is using aluminium arrows he can add

lead o he inside o he poin o increase is weigh. I is

obvious ha you can cu off some o he arrows shaf o

shoren i bu you can lenghen he shaf wihou pur-

chasing new shafs. I you increase bow weigh you may

ge o he poin he bow is oo heavy or you o conrol.

BowsringServing weigh (cenre serving) can affec dynamic spine.

For example, monofilamen cenre serving will cause hearrow o reac siffer han ligher weigh nylon cenre

serving. Simply changing rom a meal nocking poin o

a ie-on nocking poin can have a noiceable affec on


11/17


arrow spine due o he weigh difference beween he wo

syles o nocking poins.

Objecive o Bow TuningTe goal o uning your bow is o se i up so ha you

can ge he smalles group possible wihin your shooingabiliy.

Many people look or he bes arrow fligh or being

able o shoo bare shafs ino he fleched shaf group.

Tere are many incidences where elie archers ge excel-

len groups wihou perec arrow fligh. I is also normal

or he bare shafs o hi jus ouside he fleched shaf

group. Since bare shafs are ligher han fleched shafs

and have a no rear weigh (he flechings), depending on

he disance being sho, i migh be expeced ha he un-

fleched shafs would hi higher and o he lef (righ handarcher) o he fleched shafs.

Saring he Tuning ProcessFollow he many available manuacurers spine chars o

selec he arrow size recommended or your draw lengh

and bow poundage o use as a saring poin in develop-

ing he proper arrows or you. Read all o he inorma-

ion provided on he proper use o he char. Many peo-

ple have ound ha he arrow sizes recommended by he

manuacurer is a leas one siffness grade oo siff so i

may be wise o ry he arrows or pick one grade less siff

shaf as a saring poin.

Verificaion ha you have seleced he correc spine

will be deermined during he uning process. Problems

caused by improperly spined arrow shafs will become

eviden during his process. Beore uning, be sure ha all

arrows are sraigh, properly fleched, and have perecly

aligned nocks. Now ha you have compleed he prelimi-

nary adjusmens and properly se up your bow, you areready o sar he uning process.

Esablishing a Basic TuneI is suggesed ha you begin wih he Bare Shaf es.

Shoo bare shafs a a arge a m. In his way you will

see how he shaf leaves he bow and you can adjus your

nocking poin and cushion plunger as needed. Adjus he

nocking poin as shown in Figure .

Figure .

Figure .

Fishtailing: (caused buy mismatched arrowspine).I he arrow leaves he bow wih he nock end leaning o

one side or he oher, fishailing occurs. Te nock end o

he arrow will appear o move rom side o side as he ar-

row ollows is fligh pah. See Figure .

Figure .

Using he Bare Shaf Planinges o correc fishailing,

coninue o shoo hree fleched shafs and wo or hree

idenically aimed unfleched shafs. Again, make sure hebare shafs will hi he arge beore moving back urher

han yards. I he unfleched shafs impac lef o he

fleched shafs, he arrow is oo siff (or a righ-handed

archer, opposie (weak) or a lef hand archer). I he bare

shafs impac more han o inches ( o cm) a

yards, his will mean ha he bare shafs will be well away

rom he fleched shafs a a longer disance like me-

ers and may no even hi he arge. In his case, is no

likely ha any decrease he spring ension on he cushion

plunger will be much help. I is beter o use a more effec-ive gross adjustment, or a combinaion o adjusmens

beore working wih he cushion plunger (making sure

ha he cushion plunger is sill se a a medium spring en-

Arrow shafs are w ithout etchings.

Te nocking point is too high.

Arrow shafs are w ithout etchings.

Te nocking point is too low.


12/17


sion). I your bow weigh is adjusable, increase he bow

weigh by approximaely pound. An adjusmen more

han one pound is no recommended unless he archer is

in very good physical condiion and even hen an archer

should never increase more han pounds a a ime as i

could have derimenal affecs on shooing echnique andpossibly induce an injury. Oher gross adjusmens ha

will improve he spine compaibiliy o an arrow ha is

oo siff are an increase in arrow poin weigh and a reduc-

ion in he number o srands in he sring (reducing he

physical weigh o he bowsring). In he same relaion,

a decrease in he weigh o he cenre serving maerial or

a decrease in he lengh o he cenre serving will have a

similar effec as well as a reducion in he weigh o he

nocking poin (example: changing rom a meal nocking

poin o a ie-on ype).I he unfleched shafs impac righ o he idenically

aimed fleched shafs (weak), (or a righ-handed archer,

opposie (siff) or a lef hand archer), decrease bow

weigh slighly (i your bow weigh is adjusable) and or

decrease arrow poin weigh. Here, he bow weigh would

be your bes adjusmen o move he bare shafs ino or

near he same group as he fleched shafs. Going down

in bow weigh is no a problem oher han losing a litle

arrow speed. Your equipmen is basically uned when

he bare shafs and fleched shafs impac a he same or

very near he same locaion. Once you have compleed

he Fine uning process do no be surprised i he bare

shaf impac changes. I is common on a well-uned bow

o have he bare shafs impac a differen locaion han

he fleched shafs. Usually, a good une will have he bare

shafs impacing close o he fleched shafs in he hori-

zonal plane, bu i he nocking poin heigh is no correc

he bare shaf impac posiion may be slighly higher or

lower han he fleched shafs impac posiion.

Cushion Plunger SetingWhen correcing fishailing using he Bare Shaf Planing

es, use he cushion plunger or fine adjusmens only and

no or large horizonal adjusmens. I is imporan o firs

have good spine compaibiliy or he bow beore using he

cushion plunger o correc gross errors in spine. In he fine

uning process, he cushion plungers abiliy or improving

grouping will become eviden. Also, i is imporan o noe

ha when adjusing he cushion plunger ension, i will al-mos always affec nocking poin heigh as well as dynamic

spine. Don be surprised i he bare shaf impacs change in

heigh as well as horizonal impac.

I during he uning process you are unable o ge he

unfleched shafs o impac near he fleched shafs in

he horizonal plane, i will mos likely be necessary o

change arrow sizes. Your arrows migh be oo weak (he

unfleched shaf impacs o he righ o he fleched shaf

or righ-handed archers) or oo siff (he unflechedshaf impacs o he lef o he fleched shaf or righ-

handed archers). I, afer compleing his es, he bare

shaf impac is more han inches ( cm) o he righ

(weak) or lef (siff) o he fleched shafs a yards

( m), you will mos likely need o change shaf size.

However, beore going o his more cosly invesmen,

make sure you are no having a alse uning indicaor

caused by a clearance problem. Usually, incompaible

arrow spine is he bigges cause o a clearance problem,

bu no always.

Clearance

o check or clearance, use dry powder oo spray, dry

deodoran spray or similar produc applied o he las

quarer o he arrow shaf, fleching, arrow res assembly

and sigh window near he arrow res. Do no disurb he

powder sprayed on he arrow and bow while preparing o

shoo. Te arrow should be sho ino a firm arge so ha

i will no penerae o he powder area. Ten check he

powder on he arrow o see i here are any marks indica-

ing an impac beween he arrow and bow.

Correcing Clearance ProblemsI you are no achieving good arrow clearance, and he ar-

row fleching and bow make conac, opimum grouping

canno be achieved. By examining he areas where he dry

powder spray is scraped off, he naure o any inererence

can be deermined, and he posiion o he fleching as he

arrow leaves he bow can be idenified. I here is a clear-ance problem, his can usually be seen in he arrows fligh

o he arge. A erm used o explain he visual fligh disur-

bance is called Minnowing. Like fishailing or Porpoising,

Minnowing describes a specific arrow fligh disurbance.

Minnowing will appear o look much like fishailing ex-

cep ha he ail o he arrow appears o move rom side o

side more quickly, and he amoun o side swing is usually

much less han in fishailing. See Figure .

Figure .


13/17


Minnowing indicaes inadequae clearance and is caused

by he rear porion o he arrow (usually fleching) con-

acing he arrow res or cushion plunger. Te ollowing

procedures can help you correc clearance problems ha

cause minnowing:

I he arrow fleching is hiting he arrow res, ry ro-

aing your arrow nock o a urn. Coninue roa-

ing he nock in -urn incremens unil clearance is

achieved.

Make sure your arrow res suppor arm does no pro-

rude pas he ouside o he arrow shaf when he ar-

row is resing on he suppor arm and is lying agains

he cushion plunger or side loading device. See Fig-

ures 5 & 6.

Choose a lower profile fleching.

Follow he procedures or uning Adjusmens or

nock indexing and arrow res se up.

Make sure he bow hand is well relaxed o eliminae

bow hand orque.

Move he cushion plunger slighly ou rom he bow

o help increase clearance i he oher uning modifi-

caions have no effec.

Trouble-Shooing Arrow Groups

You may have heard someone say, I your arrows group

well a yards, hey will group a any disance, or, I

your arrows group a long disances, hey will group a

shor disances. In some cases, neiher saemen is rue.

Tere may be a minue disurbance in he equipmen ha

affecs he equipmens poenial or superior accuracy

causing poor arrow grouping. Wha ollows here is inor-

maion ha will help you perorm he fine uning adjus-

mens necessary o eliminae mos or all o he minue

uning problems.

Many archers have experienced one or all o he ol-lowing arrow grouping/arrow fligh combinaions: poor

arrow fligh and good grouping. Tis is commonly he

resul o a siff arrow. Te arrow yaws slighly as i leaves

he bow, bu usually recovers quickly and ofen produces

very accepable grouping.

Good arrow fligh and poor grouping. Alhough his

seems conradicory, he phenomenon is somewha com-

mon and relaes o he uning mehod used, or a lack o

fine uning. Having perec arrow fligh, or having he

bare shafs impac exacly wih he fleched shafs usinghe Bare Shaf Planing es, does no always mean your

arrows will group well; i only means he arrows fly well.

Te secion on Fine uning will assis you in obaining

opimal grouping rom your equipmen as well as good

arrow fligh. I is bes o work oward good arrow fligh

and good grouping as his wil l produce he mos consis-

en resuls in any weaher and especially windy condi-

ions.Arrow grouping paterns ofen reveal probable arrow

fligh problems. wo o he mos common grouping in-

dicaors or deermining arrow fligh problems are de-

scribed below.

Excessive DragI he arrow has oo much drag, ha is he flechings are

oo large or he flech are off-se oo much, i can cause

excessive drag and grouping will ofen suffer a long dis-

ance. For example, i shooing FIA disances o , , and meers or men and , , and meers

or women, you may experience good grouping on all

disances excep or he longes disance. I his is he

case, he arrow mos likely has oo much drag. Exces-

sive drag will cause he arrow o become unsable due

o he rapid decay o is orward velociy. When orward

velociy drops oo quickly, insabiliy occurs. Tis un-

sable fligh causes poor grouping a long disances and

exreme vulnerabiliy o wind drif. On lighweigh ar-

rows, i is very imporan o reduce drag o a minimum

o mainain maximum downrange velociy. Tis can be

done by reducing he size (heigh and/or lengh) o he

fleching or by reducing he angle o he fleching, or

boh.

Insufficien ClearanceA clearance problem will usually have he opposie effec

o excessive drag. Mos ofen arrow grouping is accep-

able a longer disances, however, he shorer disancegroups are no reduced in size proporionaely o hose

a he longer disances. Tis siuaion commonly resuls

in shor disance scores ha are significanly less han

wha he longer disance scores would indicae. I his is

a amiliar scenario, look or a clearance problem or micro

disurbance wihin he bow and arrow sysem. o correc,

see he secion on Clearance.

Adjusing he Bow and Arrow Sysem

I you are having problems uning your bow, you willneed o make some modificaions o your equipmen o

achieve a beter une. Here are some suggesions:


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Bow Weigh AdjusmenVirually all arge qualiy recurve bows have an adjus-

able draw weigh sysem. Bow weigh adjusmen should

be he firs uning consideraion i your arrow reacion is

significanly siff or weak. I is imporan no o increase

bow weigh more han one o wo pounds as i could havederimenal effec on shooing echnique. Here is a good

guideline o ollow o know i you can physically handle

any increase in bow weigh. Simply draw and hold your

bow a ull draw or seconds. I i you can hold he

weigh or an enire minue, you can handle he one o

wo pound increase. I he arrow reacion is oo siff when

applying he bare shaf uning es, increase he draw

weigh. I your arrow reacion is oo weak, decrease he

draw weigh.

BowsringBowsring weigh can have a significan effec on arrow

spine. Increasing or decreasing he number o srands in

he bowsring can influence he arrows dynamic spine

enough o require a shaf size change o up o one ull size

weaker or siffer. I your arrow reacion is oo siff, decrease

he number o srands in your bowsring. I your arrow re-

acion is oo weak, increase he number o srands. Serv-

ing weigh (cenre serving) can also produce he same e-

ec. For example, monofilamen cenre serving will cause

he arrow o reac siffer han ligher weigh nylon cenre

serving. Simply changing rom a meal nocking poin o

a ie-on nocking poin can have a noiceable effec on

arrow spine as well due o he weigh difference beween

he wo syles o nocking poins.

Poin and Inser Weigh

Te arrows dynamic spine can be uned by using various

poin and/or inser/ouser weigh combinaions. I yourarrow is oo weak, go o a ligher inser or poin. I your

arrow is oo siff, ry a heavier inser or poin. Coninue o

change inser and/or poin weighs wihin an accepable

balance poin range ( F.O.C.).

Documening EquipmenOnce you have compleed he Bare shaf Planing es and

beore saring he fine uning process, i is imporan o

wrie down he exac measuremens o your bow. Having

all o he equipmen inormaion documened will allowyou o reurn o he iniial setings i somehing srange

happens during he fine uning process. When your bow

and arrow are ully compaible and opimum arrow fligh

and grouping have been achieved, hen you will wan o

re-documen he equipmen or uure reerence.

Following is mos o he inormaion ha should be

included in he documenaion.

a. Nocking poin heigh.

b. Brace heigh.c. iller.

d. Number o srands in he bowsring and ype o mae-

rial.

e. ype o cenre serving and end serving.

. Bow sring weigh (use a grain scale).

g. Weigh o bow a ull draw weigh.

h. ype o sabilizers used, lengh, amoun o weigh on

each rod ec.

In oher words, everyhing you can hink o o documenyour equipmen.

Nex, number all o your arrows. Tis enables you o plo

groups and o plo each individual arrow. Tis process is

very imporan in discovering which arrows group con-

sisenly and hose ha don. Anoher good rick is o

place a small do on one flech each ime ha arrow his

he ring (bes o do his only or he longer disanc-

es). Prety soon, i is clear wha arrows you will wan o

use in compeiion.. he ones wih he mos dos!

When you are ready o sar he fine uning process,

use a new cm arge ace and use i as he ploting ar-

ge. Tis will allow you o record each arrow impac and

he number o ha arrow o deermine common impac

poins or each arrow in he bunch.

Prepare o shoo rom a disance you are mos com-

orable wih rom 40 o 70 yards or meers, on a ace

size you are comorable wih, and depending on your

skill level.Shoo an end or wo o warm up beore saring he

ploting process.

Afer warming up, shoo a group o 6 o 10 fleched

arrows.

Wrie down he number o each arrow and he impac

poin on he sample ploting arge.

Shoo a leas wo groups beore making any adjus-

mens. Remember o make only one adjusmen a a

ime. When making a uning adjusmen, use a differ-

en coloured pen or each ime an adjusmen is madeor use anoher ploting arge so he resuls are no

conused.


15/17


Examine he groups or paterns o see i he group is

more verical han horizonal, more horizonal han

verical or i here is no discernable patern.

Reading he Ploted Arrow Groups

Careully examine he arrow grouping paterns you plo-ed. Noe he differen shapes o he groups and how

he adjusmens alered he arrow impac and size o he

groups. Examine each arrow by is number. ake careul

noe o any arrows ha did no group consisenly wih

he oher shafs. Monior hese shafs o see i hey are

consisenly ou o he group as you will probably wan

o mark hese shafs so you will know no o use hem in

compeiion.

Verical grouping paternsI he groups are more verical han horizonal, adjus he

nocking poin (. mm) eiher up or down. Shoo an-

oher wo groups and plo he arrows in he same man-

ner as described above. For uure reerence, be sure o

wrie down your bow adjusmen on each arrow group

you plo. Measure he disance beween he high and low

arrow o deermine an average beween he groups. Tis

will help o ideniy i he high and low arrow impac has

improved or no in he nex grouping sequence. I i has

improved, make anoher adjusmen o (. mm) in

he same direcion and shoo anoher wo ends. I he

high and low arrow impac is beter, coninue in ha di-

recion unil you achieve he mos consisen group eleva-

ion. Obviously i he verical impacs are worse, go back

o he original seting and make he same adjusmen in

he opposie direcion.

Horizonal grouping paterns

While uning, remember o coninue he documeningprocess on each ploted arrow group or he one uning

variable ha was changed. For horizonal adjusmens i

is bes o adjus only he cushion plunger spring ension,

no he in/ou posiion o he cushion plunger. Make

adjusmens o he cushion plunger spring ension in

urn incremens only. Shoo wo groups and measure he

arhes lef and righ arrows (eliminaing arrows where

known misakes were made in he echnique). Make he

firs spring ension adjusmen eiher siffer or weaker

and shoo wo more ends. Again, i he group becomeswider, go back o he original seting and make an adjus-

men o urn in he opposie direcion. Compare he

groups you jus sho and deermine i hey are geting

beter or worse. I he groups improved, make anoher

adjusmen o urn in he same direcion and shoo

anoher wo ends. Coninue his process unil you have

achieved he ighes possible grouping in he horizonal

plane a ha disance. I he groups do no change, con-

inue ollowing his procedure unil he groups improveor become wider. A he poin where he groups jus sar

o ge wider, go back urn o he previous seting and

make a small nocking poin adjusmen. Remember, ad-

jusmens o he cushion plunger will ofen have some

effec on he nocking poin and i may be necessary o

make small adjusmens o he nocking poin during he

cushion plunger adjusmens. Here is where you should

see some significan group changes (hopeully much be-

er). Remember o make only one adjusmen a a ime. I

he groups become worse, go back o he original nockingpoin seting and make he same adjusmen in he oppo-

sie direcion o compare. Coninue his process unil he

bes possible groups have been achieved wih his single

adjusmen. Ten, sar making urn spring ension ad-

jusmens o see wha happens o he grouping paterns.

Obviously i he groups are consisenly GREA, sop

and re-documen all he setings.

Te fine uning process is a dynamic relaionship be-

ween he nocking poin heigh and he cushion plunger

spring ension. Any change o one affecs he oher and i

is imporan o undersand his relaionship. When mak-

ing only one adjusmen a a ime, you will find he abil-

iy o coninually compress he up/down and lef/righ

grouping paterns ino he bes possible grouping your

skill level is capable o. Afer compleing his procedure,

you should find a combinaion o adjusmens ha will

eiher slighly or significanly improve arrow grouping.

Once you have compleed he long disance uning,

move o yards ( m) and see i he bow coninues ogroup well here oo. I should, bu i no look or a clear-

ance problem. By shooing all your compeiion disanc-

es a he end o he fine uning, you will have confidence

in knowing ha your equipmen can perorm well a any

disance when shooing compeiion.

Fine uning he brace heigh

Finding he correc brace heigh or your bow can, in

many cases, grealy improve consisency and grouping

and should be considered as a fine-uning adjusmen.Te char below shows he maximum range o brace

heigh or mos modern recurve bows. However, hese

are exreme a he high and low end o he range and


16/17


somewhere in beween is mos likely where your final

brace heigh will end up. Changes wihin he brace heigh

ranges shown can affec arrow spine as much as chang-

ing he arrow poin and/or inser weigh approximaely

grains. Remember, i is bes o shoo your bow a is

smoohes and quiees seting. Te char below showsa range wide enough o creae a beween size arrow

spine.

Maximum Recommended Brace Heigh Range orMos Compeiion Recurve Bows (by bow lengh)

- o (. cm o . cm)

- o (. cm o . cm)

- o (. cm o . cm)

- o (. cm o . cm)

Brace heigh is a fine uning adjusmen and should be

done in small incremens. When working hrough he

fine uning process, ry making a small brace heigh ad-

jusmen o see how i affecs grouping. I he sring has

very ew wiss, i will ake more urns o achieve a spe-

cific change han i he sring has numerous wiss. Make

adjusmens in very small incremens o a a ime

and see how he groups are affeced and noe any changes

in he sound and eel o he bow. I he sring has many

wiss, i will ake only one or wo urns o achieve he

brace heigh change. I he sring has very ew wiss,

i may ake or more wiss o achieve he same resul.

Ideniying Specific Arrow ProblemsYou may find an arrow ha does no group well wih he

oher arrows in he se. Examine i beore you discard ha

arrow or reire i rom compeiion. Someimes a prob-

lem is easily idenified and oher problems are no so evi-den. I a shaf is cracked or dened i should be discarded.

Some arrows may seem fine, bu hey may have problems

ha are no obvious and can cause he arrows o group

poorly. Te ollowing lis idenifies common arrow prob-

lems, which may cause inconsisen or a sray impac.

Arrow SraighnessArrows mus be sraigh or igh grouping. Sraighness

should be wihin . or beter or bes grouping. Tis

also depends where he bend is locaed. A sligh bend

near he nock end o he shaf may cause a greaer impacvariaion han a larger ben ha is over he ull lengh o

he shaf.

Crooked NocksTere are several ways o check nock sraighness, includ-

ing commercially available nock gauges and special ar-

row spinning wheels. Make sure he nocks are absoluely

sraigh. Crooked nocks can cause severe accuracy prob-

lems.

Nock Indexing

I is possible ha one nock in he se may be urned more

han he ohers. A clearance problem resuls i he nock

is roaed oo ar, orcing he fleching ino he arrow res

or cushion plunger when sho. Make sure all nocks are

indexed he same and ha he spacing beween he wo

clearance fleches (he wo vanes ha clear pas he ar-

row res and cushion plunger) is he same. When flech-

ing, i is common or some flech o be spaced closerogeher han ohers on he shaf. Always choose he

wo vanes ha are urhes apar o use as he clearance

flech.

Loose or Damaged Fleching

Fleching ha is slighly damaged will no usually affec

arrow grouping, bu i he fleching becomes even slighly

deached rom he shaf, he arrow will no group wih

he ohers. Te arrow may no even hi he arge pas

yards (meers). In he case o hard plasic vanes, i he rear

o any vane is ben, i will also cause a change in impac.

Loose Poins/InsersMany archers are no aware o his poenial problem.

Poins mus be properly insalled wih good ho mel ad-

hesive or epoxy, depending on he shaf maerial. Care-

ully ollow he insrucions on poin/inser insallaion

rom he arrow manuacurer. Some brands o ho mel

are ofen britle and may racure when he arrow impacshard arge but maerials. I he cemen racures or he

poin is improperly insalled, i can resul in a separaion

beween he poin/inser and he shaf. When separaion

occurs and he arrow is sho, he separaion o he bond

beween he shaf and poin can cause he poin o vibrae

agains he shaf wall affecing he arrows naural re-

quency o vibraion and arrow accuracy. o es or poin

vibraion, hold he arrow a ew inches below he fleching

and lighly ap he poin on carpe or grass. I you hear a

buzzing sound, he poin/inser is probably loose. Heaand pull ou he poin/inser and properly reinsall., You


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may also ge he same buzzing sound i you ap he arrow

agains he sring beore loading.

Arrow WeighArrow weigh is an imporan consideraion or ourna-

men archers and should be checked. I you have arrowsha consisenly impac a litle high or low o your group

i may be due o a sligh weigh variaion. A mached se

o arrows should have no more han a hree grain spread

beween he heavies and lighes arrows in he se. op

ournamen archers requenly mach heir arrows o one

grain or less.

In conclusion, don be araid o make uning adjusmens

as i is he bes way o learn how you and your equipmeninerac. You will learn a lo in he process and as long as

he equipmen is well documened, you can always go

back o he original setings.

Recurve Equipment tuning

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