Primitive Archer
Main Discussion Area => Bows => Topic started by: blackhawk on May 31, 2012, 11:35:09 am
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As the title states ive been wanting to try this for awhile now.....so yesterday i started thinking,plotting,planning,and drawing out a scale model of what im after. Now i havent attempted a horn bow yet so this is all new territory to me...and im usually too stubborn n cocky to ask for advice,but i think its wise i do this time.
The only person i know that has tried this was Tim Baker....hopefully Steve(badger) will chime in and give his thoughts on this one as he tested it with Tim. I dont know if he tried another one with wider working limbs than the first one(which was only 3/4"),and made the improvements on a second or third?? Steve do you remember the lentgh of the bow?
So heres my idea and drawing to scale so far(hope ya'll can read my chicken scratch)....its 51"ttt for a 50" ntn bow. 1.5" wide working limbs,and ill prob narrow it some at the handle area to around 1 1/8" or so. It will bend full compass thru the handle...the horn and sinew will feather into the fades of the levers,and then wrapped there for reinforcement. I am wanting to pull in at least 15" of reflex. Not sure if ill deflex the handle area,but i dont think i am. I have plenty of horn to play with and i can use only one strip of horn for the belly. Theres only 20" of working limbs,or should i say "limb". Im wanting to take it to 28" draw. Its a 60/40 lever to working limb ratio.
So heres my choices im at right now...i have HHB,osage,yew available for a wood core...some say osage is too heavy for horn composites,but this isnt a normal composite and all the weight will be down low and barely nothin out past the working limbs. And in my experience osage is the best wood for lever bows due to its toughness at super narraw scary ;) yew is lighter,but the levers will ding more easily as theyll be exposed....and im not to sure of HHB taking that much shear stress as its only 10" of working limb per limb. Now i know ya'll are gonna tell me maple..right? Well,i aint got none. I suppose i could go cut some tho. But this design doesnt look like it will be as stressed as a turkish horn bow so maybe the woods i listed wood work if done right. And wood i have to make sure i have matching grooves for the horn n core with this design? Adam states its not so important in lesser stressed designs to have matching grooves,but it increases the chances of longer lasting durablility in doing so.
So yes...i do have Adams book. Anyways heres the first scaled drawing
(http://i1181.photobucket.com/albums/x436/blackhawk28/2012-05-30_12-38-07_210.jpg)
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Go for it !!
Looks like a blackhawk bow to me !!
Have fun !
Guy
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Blackhawk,
I've also read Adam's book a time or two.
What about a Mulberry core?
I have some mulberry aging with just such a bow in mind.
Look forward to seeing this bow come together.
-gus
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i know nothing about horn sinew , but build it first using wood glued in reflex to scale . and then decide if horn sinew could improve on what you have . upside to this way is you have two bows to play with , one while you wait for glue to dry
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Crazy cool idea!! I hope it works, and can't wait to see some pics. A build a long would be awesome...hint, hint!!!
Tattoo Dave
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Blackhawk - i'm making one of these right now...I think this design has GREAT potential.
First osage will work but you will find that because there is such a difference between early/latewood then you will likely get depressions in the early wood. Trust me on this one. Of course the best way to overcome this if you are using osage is to use it 1/4 sawn. However it becomes less laterally stable this way.
Why not use some kiln dried maple? It works fine and will (obviously!) already be in board form. Flawless straight lines = essential, no matter what anyone tells you.
Maple is the key choice due to it's liking of glue and at the end of the day the master Turkish bowyers knew their stuff. Sure experiment away but they had already done all the experimenting and therefore KNEW (not guessed!) what to use. I managed to get away with using cherry for my core before I figured out everything I needed know to succesfully bend kiln dried maple.
Mulberry was used for the spliced in kasan/tips due to it being able to be bent like butter with steam. It's not really suitable for cores.
You definately want a diffuse porous wood for the core because these woods are more like homogenous materials compared to ring porous woods. I used elm on my very first core and it sheared along the earlywood..... I think osage works (but only just) due to it's bad ass toughness!
Matching grooves are not essential but if you follow Adam's technique of the scraper with the projecting/moveable foot then it isn't difficult. DO NOT touch the mating surfaces of the horn and core with bare hands - get yourself some cotton glooves.
Personally I think it's a better idea to have a rigid handle and fades. You need to really stress the horn or else it will be slow/soggy shooting. Don't worry about the horn/sinew not being able to take the bending
http://i492.photobucket.com/albums/rr283/mikekeswick/074-1.jpg (http://i492.photobucket.com/albums/rr283/mikekeswick/074-1.jpg)
Most Turkish bows are in the region of 44 -48 inch long and they have rigid kasans, the sal being less than a foot.
Good luck.
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Ill first state here that my computer is still trying to process this all,so forgive me of my "thinking out loud here"....
Thanks for being my personal cheerleader guy ;)
Dont have any mulberry gus,but sounds like not so great for a core...and white mulberry was used..not sure what type you have? And what exact type of horn bow are you wanting to make?
Ken..ive already built plenty of lever bows self and grass backed with 0-3" of setback after all is said and done...and it seems like this is the best and most i can come up with as far as results there....so the horn n sinew wood allow me to put in a HUGE amount of reflex and keep it...if i was to induce that much in a wood backed lam or selfbow it wood not take the strain....im already straining them as far as they can go...horn n sinew are the next progression for me with them,and it seems only logical to do so,and i also think it has great potential
Dave...not sure about a build along as ive never done this before and wood be totally winging it...but maybe its a good idea to post my progress as i go for advice n tips from folks
Mike....(ill take a big deep breath before i start).....wood you care to share your specs of yours and the whys? If not here maybe send a pm if ya dont want all to know your secret powerhouse in the works...but if we collaborate together then i beleive much can be solved to figure out the best way for this design. I know maple is great as a core but its only so so for in levers,especially in a 60/40 ratio design with edge grain kiln wood(not good at all for lateral stability and wood need more mass to keep em stable being so long n narrow attached to highly reflexed limbs)...sooo what im looking for a wood that wood be a compromise between core and lever....im thinking a clean HHB stave might be the ticket...its good core wood,and the levers wood be in stave form,meaning the best for stability and rigidity,and you could go less mass as possible this way instead of any edge grain wood.......as far as the bendy handle i wood be able to retain a better string angle as levers arent gonna retain as well as a siyah does,plus you wood be able to really reflex it hard thru the handle and wood be stressing the horn plenty with only 10" of horn per limb.......the otheside to that is if i did put a stiff handle in i could do as Tim intended and did with the andaman holmgaard bows and make a long stiff center section,but still have the same ratio of working limbs as the one i drew up...thoughts there?? String angle wood be low,but limbs wood be stressed the same,and the mass in the working limb and levers wood be the same,and might have even greater cast this way as its a longer bow?? Ok my brain is hurting....i need to stop n take a breath............
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Chris, I am trying to recall the bow. Tim and I tested so many none of them really stand out anymore. The only one similar that I can recall was like 76" long. For a bow like this I would consider hackberry as a great core wood. Hackberry can be shaped with steam more than any other wood on the planet. I have alwasy felt if the Asians had known about hackberry they would have been using it. At 51" long your design looks very feasable. I would consider a stiff short handle. With the short working limbs and long levers you may not need more than about 6" reflex to get those limbs working. I would think that osage or locust would be ideal for the levers. Looking forward to seeing this one. After seeing your skinny tip locust bows I don't put anything past you at this point.
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Ill donate the hackberry sliver if you need some extra seasoned stuff.
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I wood think hackberry wood be a poor candidate as a core because its ring porous,and wood be poor for gluing.....but i wont dispute its bending properties ;)
Maybe there wood be a way to splice in osage levers in a maple core? Actually yes i do believe i could....just splice it out past the fades to the levers....but that wood account for more weight in the limbs due to being a lil wide at the base of the levers for the splice with reinforced sinew...?? Hmmmm??
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Blackhawk - i'll post some pictures tomorrow.
As Badger suggested locust might well be a great wood for the levers. Very stiff for it dimensional volume....
I only mentioned edge grain if you were stuck on using osage (early/late wood problems with flat ringed)for the core.
If you use maple/hornbeam then flat grained is best. I think hornbeam is too dense really for a core but would work i'm sure. Maple is the best all round bet IMHO because it glues excellently, steam bends too any shape needed,diffuse porous and works easily/consistantly.
Be careful of too much reflex in the working limbs as the layers are trying to seperate during bracing...better to reflex the handle (if stiff) and splice in reflexed tip sections with only a little reflex in the working limbs. The tip splice only needs to be a 1 inch wide v-splice also no need to reinforce it there so weight can easily be kept low.
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W splice front to back inside the fade ?!!
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Dang Mike..ya beat me to the punch ;)..ive been wanting to try this for a year now...looks like your the guinea pig tho ;D...n maybe ill wait till yours is done to start mine so i know what to improve upon 8)........cant wait to see pics of your creation,and hopefully maybe some stats with it,like widths,lengths,and your limb to lever ratio??........i do have a clean Hophornbeam stave that might work,it has a 1/4" knot dead center of the handle,but if i make it stiff handled then it wood be fine cus the rest of it is clean as a polished whistle. Ill put some pics up of it tonight....it has a wee lil bit of twist,but i could easily heat shape and correct it after i tillered the core. Im trying to stay away from too many splice jobys...but if its not acceptable ill look for a plain sawn perfecto maple,whether it be a tree i cut or a board. I do have locust to sacrifice for levers,it does seem like a good candidate for the levers......you realize how hard those puppies are gonna slam home? >:D
Keep waving those pom-poms guy ;)
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......"you realize how hard those puppies are gonna slam home? "
Chris, surprisingly on a very fast well designed bow the tips don't slam home. The leverage is such that the arrow effectively slows them down to a near stop just before leaving the string. When they slam home you loose tons of energy. That why the light tips are so effective, partly because they accelerate faster but largely because they carry less momentum and are more easily slowed by the arrow.
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......"you realize how hard those puppies are gonna slam home? "
Chris, surprisingly on a very fast well designed bow the tips don't slam home. The leverage is such that the arrow effectively slows them down to a near stop just before leaving the string. When they slam home you loose tons of energy. That why the light tips are so effective, partly because they accelerate faster but largely because they carry less momentum and are more easily slowed by the arrow.
Then that explains why my lever tipped bows are so quiet,and ZERO handshock...and now when i shoot an "average" built bow i think its shocky.....
So let me rephrase...."you realize how hard those ARROWS are gonna slam home".... ;)
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Why not an HHB core? Its light, strong, and fast.
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so heres a possible candidate.....its a hophornbeam stave....as mentioned its clean thru where the working limbs will be....it just has one lil nipple knot dead center of the handle/stave....and you can see where the one limb just twists a wee lil bit.....its 60" long,1"+ thick in the limbs,1 1/2" thick handle section,and about 2" wide at the widest right now
so if i were to try and use this piece; here wood be my plan of attack (short version)
1. finish shape and tiller core to about an est. 30 pounds @28",except leaving the lever section with extra meat for string adjustments later
2. induce reflex to the side profile in limbs,handle,and a lil more in the levers to give me around 4-6" of setback in the core(might have to go more than that).....i wood have to thoroughly clean and degrease after
3.glue horn
4.check tiller an make adjustmenst if needed,but i wouldnt be pulling very far...just enough to get a good read
5. sinew reverse braced first course..wait a week
6. second course twisting up string for more reflex...wait a couple weeks
7. third course the same way,then let cure n season as long as i can bear to wait
hows that sound? doable? i know its a lil unorthodox from how a true asiatic is made,but i think it wood work...and any adjustments with string tracking i can make by reducing the levers when said and done,and or heating and moving them to line it up dead center down the levers and handle.....just speaking outloud here...if anyone has any other thoughts or ideas then please feel free to add,as to this is why i started the thread
heres the pics of the stave........or not,my photobucket is all messed up right now and not showing my pics.....ill try resizing n doing it thru the attachments here
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lets see if this works
(http://i1181.photobucket.com/albums/x436/blackhawk28/100_0099.jpg)
(http://i1181.photobucket.com/albums/x436/blackhawk28/100_0098.jpg)
(http://i1181.photobucket.com/albums/x436/blackhawk28/100_0097.jpg)
(http://i1181.photobucket.com/albums/x436/blackhawk28/100_0096.jpg)
(http://i1181.photobucket.com/albums/x436/blackhawk28/100_0095.jpg)
(http://i1181.photobucket.com/albums/x436/blackhawk28/100_0094.jpg)
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blackhawk i got all the confidence in the world that you won't screw the pooch on this, can't wait to see what ya come up with, Bub
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The arch nemisis better not rare its ugly face................GLUE!
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Use collagen glue.
Pictures coming later of my attempt.....
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blackhawk...Last year or so I put horn on the belly of hickory that was bamboo backed a few times.First tillering the bamboo backed hickory to about 45 pounds first.64" bows,6"non working handles.Holmgaard designs.One eighth thicknesss of horn will give you at least 15 to 20 pounds more on the bow.I used smooth on glue and just sanded lengthwise with 36 grit on surfaces to be glued.It holds fast no problem,no wrapping with horn fading into fades and levers.Only about 4" of induced reflex though.Really don't think it needed to be bamboo backed either.A little more work than heat treating bellies,but still very durable and fast.The reason I tried horn was two fold the compression strength of horn being 4 times that of wood and the weather resistant quality of the smooth on and horn.I've seen your designs and finished bows on this forum and have no doubt your project will be a success.I'm gonna try some ironwood or I suppose it's hop hornbeam.Never tried it before.It's still drying.Might put horn on or heat treat the belly.Most of my bows are osage and hickory.I shoot a 28" draw around 55 pounds comfortably.I'm not a flight bow maker by no means but do like the 10 to 15 fps faster above standard shooting standard arrows.Now if I could just shoot those 30 yard shots in a 4 inch group consistently it would be nice.LOL.I've been tuning bamboo and spruce footed arrows with osage and have concluded the best bow in the world shooting a bad arrow won't look as good as a mediocre bow shooting a tuned arrow.LOL.Put the best of both worlds together and meat is made a lot more easily.Good luck with your project.
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Oh forgot to mention the horn glued on after tillering BBH stayed in tiller every time which is a nice.Trapping the horn and side tillering a bit helped and reduced limb weight.I've got a freind who's going to glue up a laminated bow handle and all using horn on back and belly.Edge ringed osage core.I'm skeptical of not sinewing the back or at least some flax on there as horn is not as good in tension as compression I told him but it's his baby,and since I've never done it that way before who am I to say it won't work.
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Thanks for the support Bubby
Thanks for sharing your experiences beadman....sounds like a cool bow...ive been tossing around making a boo backed horn bow with a core too in this style with a lil more reflex than yours to compare the two....with a boo backing you can finish it up right away and not have to go thru the time sinew backing it,and waiting on it to cure......maybe after i get the sinew on this one,and while its curing ill attempt a boo backed one.....i think you could still pull the bow into lots of reflex with the boo and have it hold up,but ya might not retain as much reflex as a sinew backed one
One other thought ive been thinking is i wonder if a 60/40 ratio is too much,and the working limbs dont have enough power to throw the levers(the longer the levers the more power is needed to throw them)?....maybe a 50/50 is better....i still havent figured out what ratio works the best for lever bows cus they all shoot well
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Chris, I don't think 60/40 would be pusing it. I think your idea is great. The ultra light limbs would compliment a short working area closer to the handle, The closer you are bending to the handle the more energy you are storing. With ultra light limbs you are not paying the penalty for moving too much mass, I would give it a go.
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Sweet pulling bows are what I like and try to make all the time.I guess a more ambtious bow maker should have about a half dozen bows in the works to stay busy all the time so that waiting for sinew to cure is more bearable.LOL.Most of mine retain some resting reflex after settling in.I have a freind that is a quite a tester of his bows and found that with two same bamboo backed bows one with 1/2 inch of follow was only a couple fps slower than the other with 2 inches of reflex.I guess it's true that you really don't start losing much noticable cast speed until you have about 2 inches of follow or more.I hate any follow at all and am obsessed about having none at all.One of these days I'll do a sinew job and will probably get hooked by it.I need good sealing on that sinew for those foggy early morning deer hunts.LOL.
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Thanks for your confirming thoughts on the 60/40 ratio steve...i think thats about as far as a ratio you could go before you wood get diminishing returns,cus any further and it wood be too much lever for a working limb to move,and wood be an underpowered lever. Like a 4 cylinder engine trying to move a semi rig to speak in an extreme analogy..lol. and i agree with getting my bend right up to the handle for proper energy storage
Beadman...the whole string follow argument is a huge misunderstanding by most...i could go on n on with plenty of examples and reasons why a bow with some string follow can outshoot a bow with a couple inches reflex,even when same wood and draw weight n length in different bows.....theres a ton of dynamics involving that. If you detest follow then youll absolutely love the end results of a properly made and tillered sinew backed bow....go for it,just use hide glue please ;)
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Why not an HHB core? Its light, strong, and fast.
The cores properties as a self bow wood are pretty much irrelavent on a composite, it's really only acting as a stable gluing surface for the horn/sinew. What really matters is it's ability to accept glue well because the last thing you want is for the horn to delaminate. It's important that it isn't very dense to keep the overall weight of the limbs low. Hornbeam would probably work fine in my opion but it's just a bit dense.
Here is where i'm upto at the moment. I found a nice piece of locust to use for the levers! Maple working limbs and a lump of hickory for the handle. I've just got to fit the main limb/handle splices a bit better. Glue them up and then cut and glue the lever splices.Groove horn and limbs and glue up then reduce width and thickness of the core and then get it sinewed.
http://i492.photobucket.com/albums/rr283/mikekeswick/P1000721.jpg
http://i492.photobucket.com/albums/rr283/mikekeswick/P1000717.jpg
http://i492.photobucket.com/albums/rr283/mikekeswick/P1000715.jpg
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Its looking good mike...i see your gluing up the limbs to the handle setback....are you going to do the same when you glue in the levers? And are you going to slightly reflex the locust levers too prior to gluing them in? Maybe splicing everything the way your doing is better than what i planned with one piece of wood as you can line everything up dead nuts straight,and glue it all together in setback instead of having to heat induce the shape?? Hmmmm....more questions to ponder....oh and what limb to lever ratio are you using?
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blackhawk....yes I agree I've had my eyes opened wider for a while now about the dynamics of bow making.Thanks to friend bowyers and the TBB series.Seemingly never ending path.Which is good.Yes hide glue would be my choice with sinew.Just gotta make sure to let it dry properly before tillering.LOL.Got some knox gelitan and rabbit hide glue.Wintertime by my wood stove with hickory and sinew and cabin fever seems the time for me to get after those type projects. Nothing as easy and durable as a well tillered self bow though.Mike's right about these cores and their functions.Dynamics there too with density etc.Good luck with your projects. Remember success or so called luck by some is where preperation and practice meet.Thanks for sharing.:)
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Its looking good mike...i see your gluing up the limbs to the handle setback....are you going to do the same when you glue in the levers? And are you going to slightly reflex the locust levers too prior to gluing them in? Maybe splicing everything the way your doing is better than what i planned with one piece of wood as you can line everything up dead nuts straight,and glue it all together in setback instead of having to heat induce the shape?? Hmmmm....more questions to ponder....oh and what limb to lever ratio are you using?
Hmmmmmmmm.....questions indeed! Thats what I like about bow making - the never ending journey with no fixed destination...
I don't think there is any right or wrong really - if you can get it to work then it must be at least partially right.
I'll measure it all up and get the ratio for you.
Yes i've just heat bent the locust into a little reflex,not much because the tips will want to twist if it's excessive and then you would need to start drifting away from the advantages of these bows.
I made the handle set back because I figured it's probably the safest way to get the horn preloaded enough. The picture I posted earlier with the (not classic shape) Turkish bow shows how much it can bend,that bow is a C shape when un-strung...I plan on making the bending section very short on this bow. I'm not sure on the best way to taper the width in the bending section for maximum efficency. Badger??? ;)
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Maybe ill try it my way then n see what happens....if your making a 50/50 ratio or more then i wouldnt hardly taper the width to your working limbs IMHO,but thats just what i have found out works best for selfbows,and you might be able to taper a wee little more cus its horn,but not much.....that width will help you pull in and retain more reflex and acts as a stabalizer base to the narrow levers..thats just what ive found out in my experiences with them
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The working limbs are 13 inches (think i'll go for safety with this one!) and the tips are 15 inches long.
I got the main splices glued last night and will do the tips today sometime.
Pics to follow.
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Cool mike..thanks man for sharing your info....sounds like your going for a 60" bow then....cant wait to see your shaped frame
Right now im thinking of taking the advice of puttin in a short stiff handle and adding that to my length and making it 56" long ntn....that still gives me the same 10" working limb and 15" levers with a 60/40 ratio....i wanna bow i can shoot...i can shoot 50" bendys,but there a wild mustang to control,and putting a lil more length n stiff handle will help,plus itll give me a lil more reflex to start with,and a lil better string angle at full draw;but thats still good stats for getting that horn to work for me.
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Was just about to cut the tip splices and realised, after comparing it to my Turkish hornbows, it was way too long in the working limb. So i've cut off about 4 inches. The tips are spliced in and glued now so will be able to get some pics tomorrow.
I've got quite high hopes for this one....200fps @ 10gpp??? I don't think so but it's got the potential to be fast I think. Maybe this design is the one for the 200fps challenge with a bit of devolpment and tweaking.
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Mike...im thinking that this design is best between 60-70 lbs to try and best the 200 fps challenge...because there isnt much mass weight difference in the levers between a 40 lb bow and a 60 lb bow...and at 10gpp arrows its still maybe feasible to get them going that fast....once you start shooting the heavier arrows and weights it might be too much...i have a hankering that the sweet spot wood be between 60-70 lbs....im trying to shoot for around a 60 pound bow with mine......thoughts from anyone else on this?
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just saw this post and I have no input or experience on this subject but really look forward to a build along from you. Something I always wanted to try. The way you crank out bows I have a feeling you will make it work or learn from your mistakes real fast. Keep us posted!