TUNING

Tuning is advanced process that should not be undertaken by beginner.
Tuning on one or two boomerangs will lead to more understanding than making hundreds & not alter them
Generally tuning is done by bending & twisting the boomerang although there are some other methods.
Hot tuning is a tuning boomerang with heating up . The best way to do is using microwave oven. It will permanently change shape of boomerang
Cold tuning is a tuning boomerang without heating up. It will not last. Cold tuning can't be applied for wood boomerang. Do not confuse a tuned boomerang with a warped one.

Some tuning methods are...

1. Bending
Bending means bending the arms ‘up’ or down. Bending is usually desirable in small amounts (eg arms are a few mm ‘up/down’ from resting flat on a table) for most boomerangs.
Bending up named dihedral / positive dihedral
will increase lift to the rang & produce a higher flight
Bending down named negative dihedral / anhedral
will decrease lift on the boomerang & produce a lower flight. It is rarely needed. It is sometimes used to keep a fast catch boomerang low.

2. Twisting

Twisting alters the angle that the arms push on the air with (angle of attack).
Twist the tips up at the leading edge (counterclockwise) to give a greater angle & named positive AOA.
This will increase the lift (and the drag a bit). Increasing the lift will reduce the range of the boomerang. You can also use twisting to alter the relative amounts of lift from the arms of a two blader, and thus gain some control of how rapidly the boomerang lays over (or not) in flight.
The secret with tuning by bending is to try small changes with many throws in between to see the effect.
A lot of bending is done in tuning an MTA boomerang but it is a complex issue.

Twisting clockwise named negative AOA (angle of attack)
will increase the overall flight of the boomerang

Bending & Twisting is easy & often used by thrower because of simpler. Some plastics and plywood can be bent temporarily, and slowly ‘relax’ to their old shape, or can be more permanently altered by warming / heating them first. We may use a microwave oven, a disposable lighter, or steam from a kettle for thick ply.

3. Weighting (least destructive)
Weights are added to increase the range, and so require more initial layover in the throw. Because coins change the shape of the whole aerofoil, watch out that you are not increasing the lift at the same time, which would tend to decrease the range, or make the boomerang fly too high. Adding weight to the lifting arm where it will decrease lift is what I most often do. A coomon tip is to tape a coin to the underside of the end of the lifting arm, near the leading edge, like shown:
Remember the picture on the left is looking at the underside of the boomerang, so the lifting arm now appears on the opposite side for a right handed boomerang. People virtually always add the weight to the lifting arm as this will generally stop the boomerang from ‘laying over’ too much and give a lower flight. A bit of weighting can make a lot of difference so remember to give yourself extra space after any changes. One penny coins are good, but people also use lead strip. Sometimes the range can be usefully increased by a few layers of tape with no coins / lead.

4. Flapping
Strangely, more drag can be beneficial at times. Most often this technique is used to stop boomerangs drifting downwind or to slow them down for an easier catch. Use a bit of sticky tape with a ‘pinch’ in it so that it sticks out from the surface. The more area sticking out, the more drag. I usually add the flaps to the top surface, as shown, but this is just a personal preference. The position of the flap is important ; nearer the tips will do the most to reduce spin, whilst nearer the centre / elbow will slow the boomerang down with least reduction of spin.

5. Drilling Holes
This is a more permanent way to add drag and very commonly used. Holes are usually about 3-5mm. Lots of fast catch and high wind boomerangs have holes. Holes near the tips do most to reduce spin, while near the centre they reduce speed.


6. Filing away material to change the cross section (most destructive)

Removing more material from the leading edge will reduce the amount of lift. This is useful because the boomerang will fly further, if you can throw it hard enough. (Throwing the same boomerang harder usually does not increase the range significantly: it just goes around faster). It is often particularly useful to alter the lifting arm in this way to reduce the amount of ‘laying over’ that the boomerang does in flight. Reducing the tendency of the boomerang to lay over will keep the flight lower, and may make it more circular. A boomerang with less lift will need more initial layover, when it is thrown. Basically, the less lift, the longer the range, the more initial layover. Having less lift from the lifting arm stops the boomerang laying over more and climbing too high as it flies.
Very long distance boomerangs have a cross section / aerofoil that is virtually the same for the leading edge as the trailing edge, and also as much material is removed from the bottom as the top so they are virtually the same on top and bottom surface.

7. Combs
These are slots cut into the boomerang's edge. They give lots of wind resisitance and also increase range. They have more effect on the leading edges, near the tips.

Summary – Tuning

Mix & match until you have the boomerang tuned to your throwing style & remember when you have tuned the boomerang to fly a certain way under a certain type of wind condition. Do not expect it to fly perfectly an all conditions.

Tuning boomerangs also can give a lot of insight into how boomerangs work and controlling their flight, but take it slow. Change one thing at a time and make many throws to fully see the changes. Be prepared to alter your boomerangs after they have been made. Even if you ruin one, you can always make a new better one with what you have learned.

more about tuning, please visit the links below :

Boomerang Tuning by Kendall Davis

Flying Frog - B Manual

Gel's Tuning Tips 

BBS - Tuning

Performance Boomerangs
 by Mr. Zemanudesbois is very useful for asvence thrower :

BOOMERANGTHROWING AND CONSTRUCTION MISTAKES by Rediboom

KESALAHAN MELEMPAR & KONSTRUKSI oleh Rediboom

The boomerang flies straight forward:

Bumerang terbang lurus ke depan:

·    A right-hander threw a boomerang for left-handers or vice versa.

·    Pelempar boomerang kanan melempar bumerang kidal atau sebaliknya.

·    The profiled side of the boomerang did not face the thrower.

·    Sisi terprofil (cembung) bumerang tidak menghadapi pelempar (posisi boomerang terbalik)

·    You threw much too lightly.

·    Anda melemparkan terlalu lemah (kurang tenaga)

·    The angle to the wind coming towards you was not heeded; in this case the wind was coming from behind.

·    Sudut angin datang ke arah Anda tidak diperhatikan, dalam hal ini angin datang dari belakang.

·    The boomerang has a very negative bend.

·    Bumerang memiliki tekukan (dihedral) ke bawah (negative) yang terlalu banyak

·    The boomerang has nearly no profile which is the matter with some purchased boomerangs.

·    Bumerang hampir tidak memiliki profil (yg baik) yang merupakan masalah (utama) dg beberapa bumerang (murahan) yg kita beli (tidak berkualitas)

·    The boomerang is too heavy.

·    Bumerang terlalu berat.

·    The boomerang does not get enough lift.

·    Boomerang tidak memiliki daya angkat yg cukup.

·    The boomerang is a not returning boomerang, i. e. a boomerang for hunting.

·    Bumerang tsb adalah bumerang non returning (tidak kembali), contoh: bumerang untuk berburu.

The rotation of the boomerang constantly gets weaker:

Rotasi / spin bumerang makin lama makin lemah:

·    The boomerang did not get enough rotation when it was thrown.

·    Boomerang tidak mendapatkan rotasi/spin yg cukup ketika dilempar.

·    The boomerang lacks profile or the profile is made too blunt.

·    Boomerang kurang ( tidak) memiliki profil (yg benar) atau profil tersebut dibuat terlalu tumpul.

·    The surface is much too rough.

·    Permukaan boomerang terlalu kasar.

·    The boomerang has too many holes or brake flaps.

·    Bumerang memiliki lubang atau sayap (flaps) rem (drag) terlalu banyak

The boomerang flies parallel to the ground, then descends steeply and crashes down uncontrollably:

Bumerang terbang sejajar dg tanah, kemudian turun tajam & menabrak tanah tak terkendali:

·    With most throwings the reason is sickle throwing!

·    Pada banyak kasus lemparan alasan (utama)nya adalah pelemparan sabit!

·    The angle of inclination was nearly 90, it should be approx. 20.

·    Sudut kemiringan boomerang terhadap garis vertical (lay over) hampir 90⁰ (mendatar), harus +/- 20⁰ (miring sedikit)

·    The boomerang may be totally warped. Normally, both the wing endings and the rest of the boomerang should lie flatly, e. g. on a table board.

·    Boomerang mungkin bengkok terlalu banyak. Seharusnya, kedua ujung sayap dan bagian lain bumerang membuat permukaan datar/rata, contohnya bila boomerang diletakkan pada papan/daun meja (harus menempel semua)

·    Arm 1 gets too much lift.

·    Lengan 1(sayap depan/leading wing) memiliki daya-angkat (lift) terlalu banyak.

·    The shape of the boomerang gets its average maximum lift far in front of its center of gravity.

·    Bentuk bumerang memiliki daya-angkat (lift)  maksimum rata-rata jauh di depan pusat gravitasinya.

The flight line is circular, but the boomerang grounds on its way:

Jalur penerbangan melingkar, tetapi bumerang jatuh ke tanah dalam perjalanan (sebelum sampai ke pelempar):

·    Thrown to(o) weakly!

·    Dilempar terlalu lemah

·    The angle to the horizon is too wide.

·    Sudut (lemparan) ke cakrawala (arah mendatar / garis [rata-rata] air) terlalu lebar (di bawah/ atas  garis air terlalu besar)

·    The angle of inclination is too small or even negative.

·    Sudut kemiringan ke luar (lay over)  terlalu kecil (kurang) atau bahkan negative (bagian atas boomerang miring ke dalam).

·    One or more wings have a negative horizontal bend.

·    Satu atau lebih sayap memiliki tekukan horizontal ke bawah  (dihedral negatif)

·    The shape of the boomerang gets average maximum lift right above or behind its center of gravity.

·    Bentuk bumerang memiliki daya-angkat (lift) maksimum rata-rata tepat di atas atau di belakang pusat gravitasinya.

·    With multiwinged boomerangs the whole in the center is too big.

·    Pada bumerang banyak sayap (lebih dari 2)luas penampang inti (bagian tengah) terlalu besar (luas)

The boomerang lands too far to the right of the thrower:

Bumerang mendarat terlalu ke bagian kanan (belakang) pelempar:

·    The angle to the wind coming towards you is too wide/ with the left-hander too small. (it was thrown "into the wind" / "away from the wind".)

·    Sudut antara angin datang dengan arah Anda (pelempar) terlalu lebar => bila menggunakan boomerang tangan kanan (butka) / (&) bila menggunakan boomerang tangan kiri (butki) : sudut terlalu kecil. (Bumerang dilempar "ke dalam angin" untuk butka / "menjauh dari angin” untuk butki.)

The boomerang lands too far to the left of the thrower:

Bumerang mendarat terlalu ke kiri pelempar:

·    The angle to the wind coming towards you is too small/ with the left-hander too wide. (it was thrown "away from the wind" / "into the wind".)

·    Sudut antara angin datang & arah Anda (pelempar) terlalu kecil (untuk butka) /bila dengan butki : terlalu lebar. (Bumerang dilempar "jauh dari angin" utk butka / "menjadi angin" utk butki.)

The boomerang lands too far in front of the thrower:

Bumerang mendarat terlalu jauh di depan pelempar:

·    Angle of inclination was too small.

·    Sudut kemiringan boomerang terhadap sudut vertical (lay over)  terlalu kecil (boomerang hampir  tegak lurus)

·    Arm 2 does not get enough lift.

·    Lengan 2 (belakang / trailing arm/wing) tidak memiliki daya angkat (lift) cukup.

·    The multiwinged boomerang does not get enough lift.

·    Pada bumerang banyak sayap (lebih dari 2)  tidak memiliki daya angkat cukup.

·    Check the wind direction.

·    Periksa arah angin.

·    There is no wind at all!!!

·    Tidak ada angin sama sekali!

·    The boomerang needs to get more wind.

·    Bumerang perlu mendapatkan angin lebih besar.

The boomerang lands too far behind the thrower:

Bumerang mendarat terlalu jauh di belakang pelempar:

·    Angle of inclination was too wide.

·    Sudut  kemiringan (lay over) terlalu lebar ( terlalu miring / hampir tertidur)

·    Arm 1 does not get enough lift.

·    Lengan 1 (depan / leading arm / wing) tidak memiliki daya angkat cukup.

·    The multiwinged boomerang gets too much lift .

·    Bumerang banyak sayap memiliki daya-angkat terlalu banyak.

·    Check the wind direction.

·    Periksa arah angin.

·    The wind is too strong.

·    Angin terlalu kuat.

In the first half of the flight line, the boomerang descends, but then crashes down in the second half:

Pada setengah pertama dari jalur penerbangan (jalur berangkat), bumerang turun, tapi kemudian menghunjam ke bawah pada setengah kedua (jalur kembali)

·    The angle to the horizon is too wide.

·    Sudut ke garis datar terlalu lebar.

In the first half of the flight line, the boomerang flies close to the ground, but then rises steeply in the second half:

Pada setengah pertama dari jalur penerbangan (jalur berangkat), bumerang terbang dekat dengan tanah, tetapi kemudian menanjak/naik tajam pada setengah kedua (jalur kembali)

·    The angle to the horizon is too small.

·    Sudut ke garis datar / cakrawala terlalu kecil.

The boomerang does not fly horizontally and even rotates in the wrong direction:

Boomerang tidak terbang mendatar dan bahkan berputar ke arah yang salah:

·    Arm 2 gets too much lift when compared to arm 1. 

 (Sometimes caused by the shape of the boomerang, i. e. when arm 2 is bigger, wider and thicker than arm 1.)

·    Lengan 2 (trailing arm/wing) memiliki daya angkat terlalu banyak jika dibandingkan dengan mengangkat lengan 1.

(Kadang-kadang disebabkan oleh bentuk bumerang, misalnya bila lengan 2 lebih besar, lebih lebar dan lebih tebal dari lengan 1.)

·    Shape of boomerang gets average maximum lift behind its center of gravity.

·    Bentuk bumerang memiliki daya angkat maksimum rata-rata di belakang pusat gravitasinya.

·    Boomerang is warped.

·    Boomerang dalam keadaan bengkok.

The flight line of the boomerang resembles an "S" in the final flying phase (compare to preceding point):

Jalur penerbangan bumerang menyerupai huruf "S" dalam fase akhir terbang (dibandingkan dengan titik sebelumnya):

·    Arm 1 gets too much lift when compared to arm 2.

·    Lengan 1 memiliki terlalu banyak daya angkat jika dibandingkan dg lengan 2.

·    Boomerang shape gets average maximum lift too far in front of its center of gravity.

·    Bentuk bumerang memiliki daya angkat maksimum rata-rata terlalu jauh di depan pusat gravitasinya.

·    Boomerang is warped.

·    Boomerang dalam keadaan bengkok.

The boomerang performs a circular flight line, keeps standing still above the thrower and falls down in direction to the center point of the flight line:

Bumerang ini melakukan jalur penerbangan melingkar, terus berdiri diam di atas pelempar dan (lalu) jatuh mengarah/menuju titik pusat jalur penerbangan:

·    Angle of inclination is too wide

·    Sudut kemiringan (lay over) terlalu lebar

·    Thrown too hard.

·    Dilempar terlalu keras.

·    Arm 2 gets not enough lift.

·    Lengan 2 tidak memiliki daya angkat cukup.

·    Make profile at the front edge blunter.

·    Buat(lah)  profil di tepi depan lebih tumpul

The boomerang makes some additional loops in the final phase:

Bumerang membuat beberapa putaran tambahan dalam tahap terakhir:

·    Thrown too hard!

·    Dilempar terlalu keras!

·    Boomerang does not have enough air resistance.

·    Boomerang tidak memiliki hambatan (drag) udara yang cukup.

Advanced throwers use the "mistakes" described above usually to profit from their effects within a special situation (e. g. competition).

Pelempar mahir kadang menggunakan "kesalahan" yang dipaparkan di atas justru untuk mendapatkan keuntungan dari efek “kesalahan” dalam situasi tertentu (misalnya kompetisi).

What is called a "mistake" by us is therefore a subjective term and depends on whether a particular throw is successful or not for each individual person.

Apa yang dimaksud "kesalahan" oleh kami karena itu istilah subjektif dan tergantung pada apakah lemparan tertentu berhasil atau tidak untuk masing-masing individu.