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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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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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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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Recurve Bow Equipment Tuning
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
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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.
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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 .
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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.
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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
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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.
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