Post by: joebuck on July 27, 2018, 09:58:29 AM
enough for my background..........Since 1992...my basic TD recurve bow building has been locate the center of riser then go 1.5" up and cut my radius shelf....Now i am gripping the string , 3 fingers, low wrist and the arrow is 1" above my fingers for 'crawl" or "walk".......................
So long winded.....are any of you setting your risers and or limbs up different for the crawl? I know archers have been string walking since maurice and will but now center of bow is 3.5" above nocked arrow.
Post by: joebuck on July 27, 2018, 12:31:38 PM
Post by: Mark Smeltzer on July 27, 2018, 01:49:28 PM
When I think about this stuff i throw in tiller also just to further confuse the issue. Even tiller or positive. On primitive bows some guys make the bottom limb shorter too. :dunno:
Post by: kennym on July 27, 2018, 01:51:54 PM
That seems like the bow center would be way too high? :dunno:
Post by: joebuck on July 27, 2018, 01:57:47 PM
Post by: joebuck on July 27, 2018, 02:13:25 PM
Kenny, you up to making lams out of all this persimmon? big boards are 2x12x8' :biglaugh:
Post by: Bvas on July 27, 2018, 02:39:06 PM
Tillering for string walking, I’d imagine that you would want to attach slightly lower than that. Just guessing??
Post by: kennym on July 27, 2018, 03:37:57 PM
i think on this bow i am going to attach riser to tiller board holder to exactly the place my grip pressure is by base of my thumb would be ( not center of throat of grip), then attach pulley rope to exactly where top of my index finger for three under would be................then tiller limbs accordingly....not jack with making one limb short or riser catawambpus...etc........................
Kenny, you up to making lams out of all this persimmon? big boards are 2x12x8' :biglaugh:
Any number!! :thumbsup:
Post by: Roy from Pa on July 27, 2018, 04:57:22 PM
Post by: stickmonkey on July 29, 2018, 09:17:06 AM
Post by: EwokArcher on July 29, 2018, 02:41:45 PM
Post by: Roy from Pa on July 29, 2018, 08:29:32 PM
That's not me.
I have hair..
:laughing:
Post by: kennym on July 29, 2018, 09:24:25 PM
Post by: Roy from Pa on July 30, 2018, 04:34:41 AM
:laughing:
Post by: joebuck on August 01, 2018, 09:04:15 AM
I am thinking if I lengthen the lower riser to make blue dot exact center of bow ( where now the throat of grip is the center) This would line up all three.....mathmatical center of the bow with the pressure point of correct grip and in line with my three fingers under?
Post by: EwokArcher on August 01, 2018, 09:44:25 AM
Post by: joebuck on August 01, 2018, 10:59:08 AM
Post by: EwokArcher on August 01, 2018, 12:04:26 PM
Post by: Mark Smeltzer on August 01, 2018, 12:13:25 PM
I guess they build the Yumi bow the way it is for a reason. If you figure it out let me know. :biglaugh:
Post by: joebuck on August 01, 2018, 12:16:10 PM
Post by: EwokArcher on August 01, 2018, 12:40:58 PM
Post by: stickmonkey on August 01, 2018, 01:51:20 PM
Post by: joebuck on August 01, 2018, 02:10:35 PM
I suggest that you build your bows as symmetrical as possible coming off the form, tiller them as a perfectly balanced bow out to about 20″ draw (pushing at center and pulling at center), then adjust the bow pivot position and string pulling position to match the intended shooter, and then finish tillering the bow out to full draw so the tips pull to the same distance. I think you’ll find that sliding the bow pivot up or down during the tillering process will result in a more balanced bow and limbs that are closer together in strength. What you end up is essentially a bow with equal length limbs and an asymmetrical riser. It works for compound and target bow manufacturers
Wow!!!!!!! Jim's webpage answered all my questions..........i hope he is right :bigsmyl:
Post by: joebuck on August 01, 2018, 02:32:27 PM
:dunno:
Post by: joebuck on August 01, 2018, 02:43:35 PM
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Post by: stickmonkey on August 01, 2018, 03:59:55 PM
Am i reading this right.....he says in this example....right side is upper limb. Last sentence says that making lower limb ( left limb) stronger would even tiller this bow out? seems backwards
:dunno:
Yes that is correct. More stress is placed on the lower limb as you move your hand down down the riser so keeping the left side 1/8" positive will aid it. A single point string drawing will not put the same forces on the string as the hand does however it does well enough that unless you want to go through the trouble to make a griping device that will mimic the pressures the fingers apply a little better. I made one a few years ago and still use it but again the gains from using it are very small. That said I am of the mindset of adding up all the little small performance eeks will eventually show bigger gains. I do those thing strictly for my own OCD.
Post by: stickmonkey on August 01, 2018, 04:07:26 PM
Now this scenario seems exactly what i was asking...
No surprise here. Its an asymmetrical design with both the grip and pull point being 1" Below the center of the string and bow. I am understanding that your asking about tilling to a crawl which is above the center by a few inches. The thing is you dont know the crawl till you tiller and shoot the bow so in the end its just a guess on tillering but if you dynamic tiller as we have suggested based on the drawing method it may help you make the bow quieter. in the end it may just be a wash on whats gained vs longevity of the bow.
Post by: joebuck on August 01, 2018, 04:13:01 PM
I use to shoot 3 under with arrow right under my eye.......just never felt i had a solid anchor......moving to the crawl and placing my index in corner of my mouth while keeping the arrow still under my eye.............has been Awesome
Post by: stickmonkey on August 01, 2018, 04:17:05 PM
How high above the normal nocking point on the string is your new nocking point/Crawl?
Post by: joebuck on August 01, 2018, 04:25:37 PM
Crawl "tick" bit me months ago and have decided to build a new bow and go to thinking about tiller and set up....my style has changed to low wrist, three under and dam carbon arrows!! ...........
the bow i am currently shooting i made 15 years ago and adjusted 10 years ago to even tiller....i moved string knock up to accommodate crawl and not really really shooting bullet holes in paper...I love the crawl setup so got to thinking......i want to set up my new bow to be a tack driver shooting the crawl technique
Post by: joebuck on August 01, 2018, 04:28:55 PM
Jim Thorne Fig. 11 and explanation is Exactly how my bow is set up now.
Post by: stickmonkey on August 01, 2018, 04:33:17 PM
Not sure SM if i understand your question.......but my project is for my new bow i am building...havent built one in 5 years and/or since i have changed shooting styles. ..........i shot for 20 years high wrist and split instinctive.. The last 10 i have basically shot three under and sighted down arrow like a shotgun.........
Crawl "tick" bit me months ago and have decided to build a new bow and go to thinking about tiller and set up....my style has changed to low wrist, three under and dam carbon arrows!! ...........
the bow i am currently shooting i made 15 years ago and adjusted 10 years ago to even tiller....i moved string knock up to accommodate crawl and not really really shooting bullet holes in paper...I love the crawl setup so got to thinking......i want to set up my new bow to be a tack driver shooting the crawl technique
When you say crawl I think of a fixed crawl but that is a mistake on my end as you are not fixed?
I have been building all my bows for three under with even tiller and even center on the riser , center shot and using carbon arrows , micro dia ta boot :) finding its quieter than tillered for split. Both are tillered in the same way Jim said so they are balanced at draw and timed to the gripping pressure on the riser.
Post by: stickmonkey on August 01, 2018, 04:35:37 PM
I moved knock up about 1.25"....my arrow is right under my eye and my index is in corner of my mouth
Jim Thorne Fig. 11 and explanation is Exactly how my bow is set up now.
In Jims fig 11 BOTH the grip center and string nocking point have been move down, not up. If you reverse that and move them both up then the top limb will need a little more strength to it to time correctly
Post by: joebuck on August 01, 2018, 04:40:11 PM
Post by: Bvas on August 01, 2018, 09:20:48 PM
Am i reading this right.....he says in this example....right side is upper limb. Last sentence says that making lower limb ( left limb) stronger would even tiller this bow out? seems backwardsThe right limb is not bending more. The bow is tipping in the cradle towards the stronger limb.
:dunno:
Post by: joebuck on August 02, 2018, 09:07:24 AM
Post by: TradBowyer on August 02, 2018, 04:45:26 PM
Post by: Bowjunkie on August 02, 2018, 05:07:46 PM
Bvas is absolutely correct. His bow/heavy parallel is tipping on the tree. Compare just the 'handle area' of both pics. It's tipping, I promise. Ya gotta be super careful and understanding of this, or your assessments surrounding dynamic balance will be wrong, usually completely converse of the truth, and any following efforts, misdirected.
If a bow on the tree is allowed to tip without resistance, the STRONGER limb(relative to the shooter's holds) will come down farther... and the hook on the string(string hand fulcrum) will generally always follow a plumb line straight down the wall. The key to this method is to adjust relative limb strength so that the bow isn't tipping at full draw.
On the other hand, if a bow on the tree is clamped or otherwise held so that the handle area stays level, the WEAKER limb will come down farther(relatively speaking again), and the string hand fulcrum will drift off of the plumb line, toward the stronger limb. The key with this method is to adjust relative limb strength so the hook follows the plumb line.
So long as this is understood, either method will work to dynamically balance a bow, assuming all else is properly set up... i.e. you are in fact holding and pulling from the proper places... as the archer will.
Post by: hightop_hunter on August 05, 2018, 12:05:19 AM
Post by: Roy from Pa on August 06, 2018, 01:40:18 PM
Post by: styksnstryngs on August 06, 2018, 08:04:25 PM
Post by: Roy from Pa on August 06, 2018, 09:35:33 PM
Low, medium, or a high grip and grip shape determines how your trees cradle is setup.
Post by: hightop_hunter on August 06, 2018, 09:38:41 PM
Thanks Roy for the tips
Post by: joebuck on August 07, 2018, 09:24:33 AM
Post by: joebuck on August 08, 2018, 10:26:19 AM
As of last night of shooting my current bow i have set up....with a light smell of Silver patron present....here are my dedutions
1. My current 58" curve.....just doesnt like a "crawl" set up...Arrows fly erractic.
2. The high string angle on the nock really pushes down on back of arrow at release to cause a low nock at impact.
3. Crawl it seems is for longer bows 64" 68" ( less string angle)
4. All my deciphering on where the balance center vs true center of the riser vs low grip..yada yada....doesnt matter my bow is too short. No tiller adjustment will lesson the string angle of a 52" string braced to 29.5"
5. Split finger still casts the prettiest arrow i can throw out of any bow... But Been too long on the dark side to go back. Three under it is
6. my future/ make this current project as usual design as my 58" but 2" longer on limbs
Post by: stickmonkey on August 08, 2018, 10:50:33 AM
Recurves are not as stable as deep core hybrid or longbows so using an existing bow that was not tillered/timed for how your shooting it adds to the instability of the limb causing erratic flight and oscillation. I have a 56” extreme hybrid that has a higher shelf , 2.5”, than my normal 1”. I simply tillered the limbs to where I am drawing from and it shoots just like the others set at neutral.
If you want a recurve you may consider a deep core recurve limb or an extreme hybrid but I think as long as you time the limbs from where your drawing it on the string you will be fine.
Post by: joebuck on August 08, 2018, 11:36:17 AM
Nuts and bolts of my deductions...the Crawl is for longer bows, period..
I only went to the crawl because i love the solid anchor in corner of my mouth yet my arrow is right under my eye like a shotgun...so deadly a system at 20 and in.. it's like pointing a shotgun at deer at 18 yards..
i have an unlimited supply of grizzly sticks :bigsmyl: well almost......going to try different spines
Post by: stickmonkey on August 08, 2018, 12:08:56 PM
The shape of the shooter face plays an important role in choosing a style and anchor that’s often overlooked. Three under puts the nock under my dominat eye but I have to push hard and deeply into the corner of my mouth to get the same with split finger. When I started 30 years ago I shot split finger as it kept the arrow inline under my dominant eye but as I matured and gained weight in my face my anchor had to change to keep the same alignment.
The crawl is nothing new and the bows length doesn’t matter if it’s tillered to where your drawing on the string. Yes The higher you go on the string the steeper the angle but that angle doesn’t cause an torsional instability to be induced reguardless of the bows length. The erratic light is a product of the limbs not being timed to the where your drawing on the string.
Time to build it and see.
Post by: joebuck on August 23, 2018, 09:58:42 AM
Tillering for the Fixed Crawl...to the nuts and bolts.......I tillered the bow by placing the fulgram of handle on pulley board wall exactly where pressure is for my heel/base thumb. Then i hooked up pull down hook on string exactly where my middle finger ( center) of my 3 under grip. I then tillered the limbs at 30" to Even tiller on the wall graph. Interesting point here is .........this bow upper limb is 1/8" negative tiller at brace.! Since it is shooting like a lazer with bareshafts...........I am cool with a slightly stronger upper limb at brace. not sure of the physics or what but second set of limbs will be in works soon to get more data.
Right Now for my Data and stats to build a bow for fixed crawl
60" T/D recurve ( 27 " limbs and 16" riser)
50# at 29"
1/8" negative tiller at brace upper
Even tiller at 30"
590 gr arrow 171fps at 29"at 50#
500 gr arrow at 50# at 29" 190fps at 10gr/per pound