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MikaNuotio
Joined: 06 Sep 2004
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jmpaaso
Joined: 25 Nov 2004
Posts: 32
Location: HML
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 Posted: 31.12.2004 20:03 Post subject: Re: Jousen rakentelua |
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hieman omia mielipieteitä. kaikki ei ole itse testattuja mutta luettuja.
Kaikki epoksit eivät välttämättä ole ihaantellisisa tai soveltuvia jousen laminointiin. johtuen lähinnä siittä että jotku epoksit ovat liian kovia/"lasimaisia" ja heti kun saumaa venyttää (jousen lapaa jännittää) sauma paukahtaa rikki kuin lasi. njet ist good. Eikkä jotkut soveltuu paremmin kuin toiset. Tosin 2 komp epoksit ovet yleisesti ottaen soveltuvia....mutta ei kaikki.
PUR/polyuretaaniliimat... vaikuttaisivat ihaanteellisilta mutta mieleen tulee sellainen juttu takavuosilta: lais/hiili-kuitu lavoissa käytettiin väliaineena mm polyuretaania (puun sijasta) homma toimi hiton hienosti hetken aikaa kunnes polyretaani alkoi murtua ja homma meni lööperiksi... voipi olla että PUR liimalla *saattaa' olla vastaavanlainen pitkäaikainen vaikutus? onko tietoa kellään?
Cascamite tosiaan tunnetaan tänäpäivänä (tieto on n. 1 vuosi sitten) "Extramite"- nimellä.. ja valmistaja on Humbrol.
Soveltuvia liimoja mm.
tuo kommentti paksummasta liimasaumsta panee puusepän niskaan näppylöitä... en tiedä varmasti mistä se tulee mutta yritän selventää omia mielipiteitä. Ilmeisesti on yritetty sanoa: ettei käytä liian suurta puristusvoimaa liimaus vaiheessa. Eliikkä monelle epoksi liimalla on sellainen taipumus puristua poijes liimattavasta saumasta JOS "puristus paine" on liian iso. Jokaisella liimalla on se oma ihaantellinen puristus paine/voima. PVAc liimoilla se on sen verran alhainen että wanha kunnon winka riittää puristamaan... epokseilla se vaihtelee mutta yleensä epoksit eivät kaipaa normaalia winkaa enempää (ja joskus sekin tuppaa olemaan liikaa jos puristimen vääntää kiinni otsasuoni pullottaen) . wanhoille fenoli(/resorcinoli liimoille ruuvi puristin ei riitä vaan vaaditaan hydrauli voimaa)...
Eliiiikkä, kannattaa selvittää mikä on kunkin liiman suositeltu puristus voima yleensä sen saa valmistajalta selvitettyä jos purkissa ei lue. En nyt tähän hätään muista (vaikka pitäisi) ulkoa mitkä ovat osviittaa asntavat nyrkki säännöt kullekkin liimalle... ehkä ky´syttäessä voin kaivaa tiedon esiin. :-)
Suurin osa jousen tekoon vaativissa liimauksiissa riittää tuo vinka mutta sen kanssa pitä huomioida että jos epoksia liimattessa vääntää puritimen "otsa suoni pullottaessa" niin todennäköistä on että liimaus voima on ollut liikaa ja varsinainen liima on pursunut poijes saumasta. joten sauma "ist kaputt"
No saatatte ajatella että saumasta ei saa pursua mitään ulos... okei - väärin . Yleinen tapa onkin ettää liimaa levitellään "liikaa" ja sitten kun laitetaan puristukseen , niin jokapuolelta olisi syytä pursuta edes vähäsen liimaa ulos... tämä nimittäin tuo sisällee jääneet ilma kuplat ulos( hyvässä lykyssä)
jotenka loppupäätös: paksu liimasauma ei ole hyvä juttu. siinä on liian paljon turhaa painoa, toisaalta se on varmempi kuin ihan hiuksen ohut liima sauma kun se on liian ohut. Liimasauman on oltava "just eikä melkein" . Näin ainakin puusepän mielipiteitä... toisaalta puusepän opissa harvemmin kohdataan jousen tekoon liittyviä perusoppeja, ellei sitten harrasta ... ja jokaisen normaalllin huonekalun liimauksen yhetydessä "piruuksissaan" tee muutomia koeliimauksia joita sitten testailee (tosin ei mitään empiirirstä) .
Liimasauman paksuus riippuu.
A. käytettävästä liimasta
B. puristus voimasta
mikä sitten on se optimaali? -en tiedä, se vaihtelee.
Sitten vielä se kolmas tekijä: liimattavat puulajit? kaikki liimat eivät välttämättä sovellu suoraan kaikille puulajeille... ihan esimerkkinä kun teak viilua liimataan vaneri/LASTULEVY/MDF tms niin pvac pelkästään ei sovellu... teak kun on nk. rasvainen puulaji niin olisi syytä jkoa acetonilla putsattava pinta just ennenkuin liimaa jotta varmistaa liimasauman kestävyyden. jotkut epksit kuuleman mukaan soveltuvat suoraan ilman acetoni käsittelyä (en tiedä. tämä on wanhojen gurujen mielipide)
periaatteessa kaine mitä olen lukenut koskien pvac liimasta (erikeeper/66/B3 jne) niin sen EI pitäisi soveltua metsästys jousen laminointiin! Siis tämä on luetun pohjalat ja sen mitä olen em liimoja käyttänyt. Tosin olen tehnyt yhden 55# pyramiidi jousen jossa kärki nokit ja kahva on pvac liimattu ja toistaiseksi on kestänyt... voipi olla että kestää hyvinkin ottaen huomioon että jotkut palstalle kirjoittaneet (+muutomat muut) ovat kirjoitelleet kokemuksistaan pvac "laminoiduitsa" jousista) hyvinkin positiivisiä kokemuksia...mutta oliko kellään nk. metsästys vahvuinen jousi?
elikkä nämä mietteet tällä erää... Rauhallista vuoden vaihtoa... ja siittä uutta vuotta myäs.
trev. Juho Paaso
-Epokshit
-Ristiinlinkityt PVA liimat väri kellertävä(PVA II (cross linked polymer)color Yellow)
-Polyuretaani puuliimat
-Cascamite liima (Cascamite was the name of a general purpose powdered resin glue suitable for all kinds of applications. It is now marketed as Extramite and I think it is made by Humbrol.)
-Eläinliimat
...
Ylipäätään hieman paksumpi ja täyttävämpi puuliima on soveliaampaa laminointiin kuin ihan ohut.
...
Kuinka nopeita tälläiset jouset ovat keskimäärin.
http://www.primitivearcher.com/articles/howfast.htm
Jousenselkä (backing)
http://www.primitiveways.com/cordage_backed_bow.html
http://www.primitiveways.com/secrets_of_sinew.html
http://www.primitivearcher.com/articles/hick-back.html
http://tradarchery.prohunternetwork.com/redrover.html
...[/quote]
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MikaNuotio
Joined: 06 Sep 2004
Posts: 534
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| Posted: 31.12.2004 20:10 Post subject: |
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Paksumpi liima, ei paksumpi liimasauma. Kova puristus ja liika pursuaa pois ja liimasauma on näkymätön parhaassa tapauksessa.
Moni tekijä käyttää liimaa jonka notkeuden voi itse sekoittaa halutuksi. Eriasia on huonekaluteollisuudessa jossa käytetään ohuita maitoliimoja jotka toimii tarkoitukseensa hyvin.
Menneiden vuosien kehnot polyuretaaniliimat ovat historiaa mutta niitä kyllä oli. |
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jmpaaso
Joined: 25 Nov 2004
Posts: 32
Location: HML
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| Posted: 01.01.2005 04:27 Post subject: |
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noh..okei en sitten lukenut tarpeeksi tarkkaan tuota -ok <paksumpi liimasauma kontra paksumpi liima>
Kuitenkin, (edelleen intän kuten joskus tapana on ;-) ) mm. epoksi liimojen kanssa ei (monen) voi jouhentaa tai paksuntaa liiman nk "ford" tms. arvoa ( juoksevuutta) epoksi liimoilla sekoitus on se mitä se on ja piste! joitain poikkeuksia on: esim sekoittamalla "pii-tuhkaa" liimaan- mutta ei läheskään kaikissa ja pii-tuhka kaikessa viattomuudessaan on ilmeisesti aika pahaa ainetta (vaatiii jonkinmoiset hengitys suojat yms) ! Eli ei ihan joka pojan ainetta. Jotain epokseja voidaan saostaa /paksuntaa tms. em. tavalla ilman että liima sauman kestävyys kärsii mutta... eivät kaikki. Tämä "tieto" taas on 'experimental' rakentamisen tiimoilta...
elikkä liiman paksuuden/notkeuden valinta ei aina ole "tosta noina vaan" itsestään selvyys...
sitten tuo "maitoliima" termi... noh en ole toistaiseksi kertaakaan kuullut termiä "maitoliima" käyettettävän muualla kuin verhoilu tai kangas puolella... (huom . ei "PUU"sepän työssä, vaikka pintakäsittely ja verhoilu sitä liippaakin läheltä) joten en osaa sanoa siittä muutta kuin että olen liimannut nahkaisen nuoliviinin (mallia. robin-hood/Howarda Hill) sillä ja se on kestänyt hyvin;-) tosin siinä on kunnon tikkaus lisänä!
jotta minun kommentteja ei ammuta alas.. haluan ilmaista vaan että suurin osa Mika Nuotion kommenteista näyttäsi olevan ihan asiaa.... ja "NE osat jotka eivät välttämättä ole TAI josta minulla on joitain eriäviä mielipiteitä..." NIIN minä nyt korrektisti yritän tuoda ilmi omat näkemykseni...!
ei millään pahalla... mutta kunhan sanon. :-)
| Mika Nuotio wrote: | Paksumpi liima, ei paksumpi liimasauma. Kova puristus ja liika pursuaa pois ja liimasauma on näkymätön parhaassa tapauksessa.
Moni tekijä käyttää liimaa jonka notkeuden voi itse sekoittaa halutuksi. Eriasia on huonekaluteollisuudessa jossa käytetään ohuita maitoliimoja jotka toimii tarkoitukseensa hyvin.
Menneiden vuosien kehnot polyuretaaniliimat ovat historiaa mutta niitä kyllä oli. |
T-
Juho Paaso
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Juho Paaso |
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MikaNuotio
Joined: 06 Sep 2004
Posts: 534
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| Posted: 01.01.2005 12:36 Post subject: |
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| 'Maitoliimoilla' tarkoitin yleisimpiä valkoisia PVA puuliimoja kuten Kiilto puuliimoja jotka sopivat ponttaukseen vallan mainiosti mutta ovat 'purukumimaisia' rasitukseen joutuessaan ja eivät ainakaan voimmakkaaseen toistuvaan rasitukseen sovi hyvin. |
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Juri
Joined: 20 Oct 2004
Posts: 3319
Location: Vantaa
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| Posted: 01.01.2005 22:30 Post subject: |
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| Ei kannata kuitenkaan sekoittaa kaseiini- eli maitoliimaan. |
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MikaNuotio
Joined: 06 Sep 2004
Posts: 534
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| Posted: 02.01.2005 14:33 Post subject: |
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Itselleni on aika tuntematon ks. maitoliima tai kaseiiniliima tai lukkoliima tai kylmäliima... En ole koskaan tarvinnut.
'Maitoliimani' tarkoittanee maitomainen tai ohut liima..
... |
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jmpaaso
Joined: 25 Nov 2004
Posts: 32
Location: HML
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| Posted: 03.01.2005 09:16 Post subject: |
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Olen käsittänyt että nykyään "maitoliimalla" tarkoitetaan sellainen valkoinen kumimainen(latex?) erittäin juokseva ja nopeasti kuivuva liima joka soveltuu lähinnä tekstiilien liimaukseen ei oikeastaan puun.. Kiilto taitaa valmistaa sitä. Liima on tosiaan purkkamainen.
Perinteinen maitoliima on sitten tuo mainittu kaseiiniliima... Sen valmistamisessa on käytetty maidon heraa... jotenkin. Siis täysin orgaaninen liima ja ei missään nimessä vedenpitävä ja kaiketi kohtalaisen altis mikrobeille/homeelle... en suosittele käytettävän jousen rakenteluun ellei sitten hae "extrme tyyppistä hupia itselleen"
Tosin jousia on kait joskus kaseiini liimoista tehty (ennen maaliman sotia?). Eikös niissä TBB1-3 kirjoissa ollut jonkinlaista osviittaa antavaa vertailua liiman kestävyydestä? itse en nyt muista ulkoa tuotakaan.
| Mika Nuotio wrote: | Itselleni on aika tuntematon ks. maitoliima tai kaseiiniliima tai lukkoliima tai kylmäliima... En ole koskaan tarvinnut.
'Maitoliimani' tarkoittanee maitomainen tai ohut liima..
... |
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Simo Hankaniemi
Joined: 08 Jul 2004
Posts: 4937
Location: Turku
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| Posted: 08.01.2005 03:33 Post subject: |
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Uutta jousta ei todellakaan kannata vetää heti täyteen mittaan. Moni jousi on rikottu tästä säännöstä poikeamalla. Puu ei alussa ole vielä oppinut taipumaan, joten jousi täytyy ajaa varovasti sisään ammuskelemalla vajaalla vedolla. Ja ennen ensimmäistä ammuskelua jousta voi pitää vireessä ehkä tunnin pari.
Koeammuntojen jälkeen jousen tapuminen kannattaa tarkistaa, sillä toinen lapa saattaa antaa enemmän myöten, jolloin vahvempaa lapaa on kaavittava siklillä tai muulla aseella kevyemmäksi. Tällä tavalla sitten jatketaan vetoa pikku hiljaa pidentämällä, kunnes vedetään täysi veto. |
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MikaNuotio
Joined: 06 Sep 2004
Posts: 534
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MikaNuotio
Joined: 06 Sep 2004
Posts: 534
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| Posted: 29.04.2005 15:08 Post subject: |
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Kestävän tuntuinen profiili saarnijouselle.
"It has settled in at 43Lb at 25", shoots 500 grains at 141 FPS. 54" long, 2.5" wide, mild bend in the handle.
Ash wood with a wallnut stain to bring out the grain, and satin polyurethane finish." |
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MikaNuotio
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muokkaus
Joined: 21 Oct 2005
Posts: 40
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| Posted: 22.10.2005 23:31 Post subject: |
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| Muotteja. |
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MikaNuotio
Joined: 06 Sep 2004
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Pitkäjousi
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| Posted: 15.11.2005 20:04 Post subject: |
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The bows that I build are hunting bows, not speed demons (but they are not slow either). I want a bow that will send a 500- to 600-grain arrow into the vital area of the game that I?m shooting at. I?m after quietness and accuracy, with enough force to bring the animal down as quickly as possible. I am a hunter, usually the last one back to camp. I don?t baby my hunting gear; I use it. This article is geared toward building your first or second bow.
I own a traditional archery shop and teach people how to build selfbows. The wood that I use the most is osage because it is ?drag-through-the-brush tough.? If you don?t use osage, make the bow longer and wider, depending on the wood chosen. I cut my own wood ? it?s not that hard. Look for the straightest tree that you can find that is free of limbs and big knots if possible. The bark should run straight up and down, not curve around the trunk. I look for a diameter that is 12 inches or larger because the larger the tree, the flatter the back of your bow. Also, larger trees give you more staves.
Once the tree is cut down, seal both cut ends with yellow carpenter?s glue, then split the log with a sledge hammer and wedge. Let the split log cure for about two years. If you don?t want to wait that long, there are plenty of wood dealers in this magazine. I?m sure any of us would be happy to talk with you.
Tools to Use
The tools that I use are as follows:
? old drawknife
? farrier?s (horseshoer?s) rasp
? small rasp rounded on one side
? medium-size pocketknife
? small chainsaw file
? various grades of sandpaper
? band saw or hatchet
? tillering string
? tillering board (or another set of eyes)
? various sharp objects
In regard to the hatchet, the second size up in the leather-handled Eastwing is the best. I find the cutting edge is thin, so it doesn?t tend to bind up as much. Try any other tool that you think might work. Use a chunck of scrap wood if you have any doubts.
One thing that I want people to know is that it?s not that hard to build a good bow. There?s enough material on this subject, it?s just hard to decide which one to choose (books, videos, etc). I think that I?ve seen or read all that there is available. It is a lot better to research than to use the ?trial and error? method that I used years ago. Just remember that anybody can build a good bow. You just have to be persistent and willing. The only thing that really matters in the finished bow is that you are proud of it (no other person?s opinion matters) and that it has enough rear end to hunt the game that you are after. In my opinion, this type of hunting or shooting is for self-satisfaction. You?re not going to take as much game or get as high a score at 3D shoots right away but, when it all comes together, these are some of the most fulfilling moments that you will ever have.
Selecting the Stave
The bow we are going to build is going to be 66 inches long, or longer, depending on draw length. The widest point on the bow is about 1 3/4 inches. You need a stave that is about 2 x 70 inches (or bigger). If you have ever built bows before, then you must be thinking that this bow is overbuilt. Yes, it is, but it will also give you years of faithful service. If anyone says that they are not accurate, well, all of the meat in my freezer didn?t crawl in there by itself! A good friend of mine, whose bow was built at my shop, has taken first place in the selfbow class for the last three years at the Texas State Longbow Championship. Although this type of bow is overbuilt to some, to me it is just what I need.
If you are using osage, the back and sapwood need to come off and a growth ring needs to be chosen for your back. There are various opinions on the thickness of the rings. The thicker the ring, the easier it is to work, but I?ve seen some good bows made with very thin rings. This is one thing about osage ? I?ve seen bows made of osage that should not have lasted more than two minutes after being strung, but they shoot for years. I?ve made some of them, and they still shoot. The ring that you want is the hard, thicker, darker one, not the light-colored, porous, spongy one. Let?s say it is 1/8 to 1/4 inch thick.
Study your stave very closely before you even take the bark off. Look for knots and pins, any curves in the grain, cracks, etc. I?ve been told that I look like I?m in a dazed state while I?m studying a stave or a rock that I?m knapping. They will let you know what they need done if you can figure out the way to listen to them. Really little things will jump out at you and say ?do this.? The funny thing is that at times it takes a little looking to get hit with something so simple that I think my son could have done it faster (and he just turned 2)!
Shaving the Bark
Take it slow, as if you?re getting paid by the hour. It took me around 30 to 40 hours to complete my first bow, and it is still shooting today. I prefer to take the bark and sapwood off with my hand axe. Just hold the stave in your off-hand with one end on the ground. A small square of plywood on the ground will prevent your axe from hitting rocks and such. Use small downward strokes. Don?t try to take off too much at one time. You have to be very aware of where any knots, pins, or dips in the grain are. If the wood starts to split out too far, turn the stave over and stop it from the other direction. Remember, go slowly, and don?t try to see how fast you can build a bow. Take your sweet time and smell the wood shavings. If you don?t like using the hand axe, try using a drawknife. Use a bowhorse or a solid bench vise and take your time.
Always keep your eyes out for knots. Do not cut through them, even if you have to go down a few rings after the sapwood is gone. When you come to a knot, you must leave it raised. Most of the time, the tree has grown around and over the area, leaving the area beefed up because it needs to be. It?s like if you were hunting in South Texas and dropped your pack to go on a stalk. Later, you come back and lever your pack out of a foot of dust with the end of your bow. You know where it is by the raised area in the dirt. It?s the same with your knot. Each layer of dust is a ring. Don?t dust them flat. Always follow the grain of the wood, whether it?s around or over.
Removing Sapwood
Now, you have you have to take the sapwood off. Use an axe, drawknife, rasp, or whatever. It doesn?t matter what you use, just use what you like and what does the job well. If the stave is wide, leave it that way for now. Choose the ring for the back of your bow (the side away from you). Just keep enough wood for your handle thickness back to belly. Find a ring that you can live with ? the thicker the better, but you can only work with what you?ve got. To work down to your ring, you will go through the thin, light, porous rings and around, over, to the side of knots. You will know where most of them are if you?ve been on the ball.
Place your stave in a bowhorse or vice. I start on the very end and work toward the other end. That?s not the only way to do it, but it is a pretty safe way. You will be going one ring at a time. Even if your ring is two or three down, go just one ring at a time. Do not try to go two rings at a time. This will give you valuable practice working knots and show you how to work the wood.
When you come to a knot or pin or just a spot that you think may give you trouble, don?t go after it with a large tool. Use a small rasp or file, pocket knife, sandpaper, or whatever, but take plenty of time and work down slowly. On knots, stop an inch or two shy all around them. I work around all of them and then come back to them last. This leaves you with the entire back complete with islands to finish. A thin-blade pocket knife and medium sandpaper work for me. I start in the center of the knot and work to the outside of the islands using the blade as a scraper. If the blade starts jumping, use a different angle. If you get chatter marks, sand them smooth and then keep going. The chainsaw file works well on knots if you use long sweeping strokes. Once you finish the entire back, sand it down to get out any tool marks that might be there. Don?t go overboard on the tops of the knots and sand through them.
Laying Out the Bow
If you left your stave wide, you can layout your bow to avoid problems. Start by leaving your stave an inch longer on both ends than your finished bow. My draw is 29 1/2 inches if I draw it all the way back. My bow is 66 inches long. Most say 66 for 28 inch draw and two inches longer or shorter for every inch added or subtracted in draw length. You may have some cracks in the ends of your stave once you come up with your length. Leave an inch on both ends for now. You can cut the ends down and get as many as you can out later.
Now, take a chalk line and snap a center line down the back. Then, get a pencil and go over the chalk for a line that will last a while. Measure and get the middle of your stave. Go two inches above and two inches below center and put two more marks. Now, go down the entire stave with lines one inch on either side of your center line. Trim to these lines with your bandsaw, hand axe, or nail file. Measure now from the center of your bow to the ends. Use half of that to get your mid-limb mark. Go from the edge of the mid-limb mark to the ends 1/4 inch over from the center line. You can use a yardstick or chalk line. Cut to these lines. Once you have these lines cut out, go the handle. You have a center mark and two others above and below.
Now, figure how wide you want your handle. This is also your choice ? some people like the feeling of a 2x4 in their hands while others like it a bit smaller. Put lines for the handle width, then four others for the flares (see illustration A). I use the bandsaw, but a coping saw works great. Whichever you use, be very aware of where the blade is on the other side of where you are looking. It is very easy to cut more than you planned, so cut a little at a time to be safe. Just as with everything else so far, you can leave more than you need and slim it down later with less aggressive tools. With this done, it should look like a bow from the back.
Now, with the stave on its side, mark lines from the handle to both tips (see illustration B). You can do this on both sides, so that you don?t overcut. Once this wood is removed, the bow building really begins.
Starting to Tiller
Tillering is only as hard as you make it. The process is to remove wood until the limbs bend evenly at the poundage and draw length that you need. Right now, the bow is just shy of about 500 pounds at 2 inches of draw with 1/4 inch brace height. We probably need it about 50-60 pounds at 28 or 29 inches. What works best for me at this point is a solid bench vise and rasp. Right now, your stave is straight from either end of the handle to the tips. The area above and below the handle is a fading slope to the limbs called a ?fadeout? (see illustration C). I don?t know of any hard and fast rules on the fadeouts. They should be a gentle transition, not abrupt. Look at as many bows and pictures as you can. There is a wealth of pictures in the back issues of Primitive Archer.
When tillering, the idea is to remove wood evenly from the entire length of the limb. If you take too much out of an area or the limb does not have a taper from handle to tip, you will get a hinge. If this is not corrected, then start your next stave. To fix a hinged area, take wood from either side. Just go slow ? if you start going fast, stop and come back later. Work each limb until they flex a little. Check this by putting a limb tip on the floor and holding the bow straight up and down, one hand on the handle and one on the other tip. Push away from yourself. Don?t try to pull a muscle, just flex it and look down the limb. You?re looking for a nice bend all through the limb (no hinges or stiff spots). Remove wood where it doesn?t bend and leave it alone when it bends too much. It?s going to take you awhile to get there, so turn on the radio. If you can get a laminated bow to practice bending on, it will help. Get your bow to bend enough to get a tillering string on, or you can use a bow stringer with large cups. (A tillering string is just an extra-long bow string ? you can tie one end off and use the loop on the other end). All we need for now is a brace height of about 3 inches. Don?t go overboard and take off too much wood. The bow should still be plenty stout now.
Using a Tillering Board
It?s now time for a tillering board (a 2x4 with a V cut in one end and notches down one side). Put the strung bow in the V and pull the string down and put it in a notch. Or, have someone hold the bow by the handle and step on the string and pull up. Only pull a few inches right now. You want the limbs to bend almost all of the way to the fadeouts, but not at the tips. Let the tips stay stiff, about 6 inches or so. If the tips have flex in the last 6 inches, the bow will be rather slow.
When the bow gets within about 25 pounds of the final draw weight, you want to put down the big rasp and go to a scraper knife and a finer rasp. Every time you remove wood while tillering, flex the limbs about 20 times so they can adjust to the new stresses they?re being put through. Just draw the bow, or stand on the string and lift up (just several inches right now). Try not to stress the bow past what you want the final draw weight to be. As you inch toward the draw length and weight, you want to watch the limbs closely for any stiff or weak spots as it is being drawn. Get someone to draw it while you?re watching. Look from both sides and from a distance and close up. Then, switch to see if both of you are seeing the same thing. If not, get a third person to look.
Fine Tillering
Slowly creep toward the final weight, but leave it about 5 pounds heavy for break-in and final sanding. As you are going, keep the belly flat and the sides the same thickness. At times, a growth ring can be much thinner on one side of the bow than on the other, so you can?t always go by the feathering of the rings on the belly. Tillering can be like hitting your head on a brick wall at times ? it just gives you a throbbing headache. It could be very helpful if you made some little bows out of scrap wood (about two feet long). They will teach you a lot in a short time and, if they break, it doesn?t matter. If they don?t break, then you have something to shoot in the house! I also tell people who are building bows with me not to worry if their bow breaks. It?s just a piece of wood ? go get another one.
As you get close in tillering, just use your knife because I think that I once lost a good 10 pounds of bow weight with one rasp stroke. The brace height should stay as low as your feathers will allow (about 6 inches for now). In the finished bow, keep it as low as the bow will shoot it. While tillering, leave the bow strung. Put the handle in a padded vice and take a little off. Then, flex the limbs 20-30 times. Repeat this until finished.
Breaking in the Bow
To break the bow in, it?s best to short draw at first. If, after you have sanded out all tool marks and shot the bow, you discover that it is too light, cut the tips down the same on both ends. This is why we left the bow long. Put new grooves in with a chain saw file. Never groove the back of string nocks like those on glass laminated bows. After the bow is sanded and rubbed smooth with steel wool, get a spoon and a glove. Put your thumb in the spoon and rub every inch of the bow to press all of the wood fibers together. Use a good pressure. With the bow held in the light, you can see where you have been.
Finishing Touches
Shoot your bow several days to make sure nothing changes, then put a finish on it. I use Tru-Oil gun stock finish. Just rub it on and let it dry. Rub lightly with steel wool and repeat. Apply at least five coats ? use more if you like. I?ve always put on a horn shelf and grip, but this is your bow, so do what you like.
A person who wants to build a bow can do so with only the information given in this article, but there is so much more information available. The Traditional Bowyer?s Bible should be a must-read. In the long run, there is nothing better than hands-on experience. Attend as many shoots, shows, and knap-ins as possible. Devour any information that you can on the subject and use what you like. The only person that you are out to impress is yourself. Get all of the back issues of Primitive Archer, read any books that you can find, ask questions, take a class, and finally, make a big pile of wood shavings and dust.
I hope to see you in a hunting or fishing camp. Spend as much time in the outdoors as you can, pass it on to your children, and be safe. |
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