Post by: Jeff Freeman on March 29, 2023, 04:47:30 PM
Post by: Jeff Freeman on March 29, 2023, 04:52:58 PM
I have been running a total of .004 tapers, .040 back .050 on the belly with a 17" riser. Fadeout width of 1.20 max.
Do I need more tapers,less tapers or a longer working limb and go with a 15-16 riser????
Post by: Jeff Freeman on March 29, 2023, 04:55:49 PM
28-29 is fine but that last inch or more. It's really adding on the poundage.
Any thoughts or suggestions 😀👍🏼
Post by: Longcruise on March 29, 2023, 07:50:31 PM
I do a 68" 1.125 at the fades, a 15" riser with .003 total taper and the same glass front and back that you use and a full length arc of reflex of about 1.25" with no wedges. It easily draws 30" without stack but next time around I'm adding a P lam. I'll be doing one of those up in a few weeks and I'll let you know how it works out.
Post by: bwatters on March 29, 2023, 08:05:24 PM
I used 2 thou taper overall and it worked quite well, however it was around 35# so take from that what you will.
Specs were:
0.040" glass back and belly
2 x 0.100" maple tapers (1 thou)
1 x 0.080" maple parallel
(for a total of 0.360" stack and 0.002"/" of taper)
68" long with an 18" riser, somewhere around 1.25" at the fades tapering down to just under 0.5"
Theoretically dropping the taper rate from 4 thou down to 2 or so should help keep the outer third of each limb from bending too much and hence should give you a bit more draw before the string angle hits that magic 90 degrees.
Post by: Stagmitis on March 30, 2023, 05:51:16 PM
Post by: Jeff Freeman on March 30, 2023, 06:04:36 PM
Post by: Stagmitis on March 30, 2023, 06:59:24 PM
Post by: Kirkll on March 30, 2023, 09:23:33 PM
I use a 20" riser and a 30" double ended power lam that extends those fades our 5" , and i use a tip wedge too. With an .004 forward taper i can get a 32" draw from a 66" bow without stacking. a 68" length isn't needed.....Only time i will shorten that riser is if i'm dropping below a 62" length.
Kirk
Post by: Jeff Freeman on March 31, 2023, 07:26:09 AM
Post by: Kirkll on March 31, 2023, 11:25:03 AM
But it can be done without it…. If you use an 18” tiller stick to hold the bow in a partially drawn position you can study the bend, make tiller adjustments and map the limbs easily.
I had a ball playing with different limb pad angles and different limb shapes and learning how all of these little things combined with taper rates, material types, and width profile all effect the draw cycle…. It’s a pretty large learning curve, but can be very satisfying, as well as challenging.
For prototyping limb design you can’t beat a take down design , and use an adjustable riser. Just changing the limb pad angle alone and increasing or decreasing the pre load using different string lengths can determine the potential characteristics for your limb shape…..
With TD limbs, once you have a form built, just shifting the stops where your wedge is located can change the whole limb’s dynamics. As well as your tip notch location and limb lengths…… it’s endless…
Once you find what you are looking for in terms of draw cycle and performance, then reverse engineer the TD bow into a one piece, and save a whole bunch of form building. Food for though…. Kirk
Post by: Stagmitis on March 31, 2023, 12:22:41 PM
Kirk how wide are you at the fade for the reccomendation above?
Post by: Jeff Freeman on March 31, 2023, 12:26:27 PM
Post by: Kirkll on March 31, 2023, 11:05:01 PM
Jeff I reread your initial post and noticed that your bows are wider at the fadeout than what I build so im not sure how usefull my post is.
Kirk how wide are you at the fade for the reccomendation above?
My rough riser thickness is 1.5” that typically comes down to 1.25” then I run a straight width profile from riser to tip width of 1/2” . Limb fades are about 6” to 7” past the riser on my TD version (long lean wedges) So at that point, I’m probably about an inch at the fades.
My one piece with the 20” riser fade to fade has a 5” power lam extension and simulates the same characteristics as the TD model. Here is a look at my riser. fades. Both the TD and the one piece I use an .004 FT and tip wedge.
Btw…. I always trap these limbs to the belly about 5 degrees through the working portion, and a bit more at the tip transition.
Post by: Stagmitis on April 01, 2023, 08:10:21 AM
Post by: Stagmitis on April 01, 2023, 08:12:15 AM
Post by: Kirkll on April 01, 2023, 11:08:01 AM
Gotcha! I found that moving past the 1" 125 Thou starts to get out of deep core territory :)
I’m kind of curious what you meant with this statement about “moving past the 1” 125 thou” and getting out of deep core territory… What exactly do you mean by this?
Post by: Stagmitis on April 01, 2023, 11:52:06 AM
Post by: Kirkll on April 01, 2023, 01:55:59 PM
I can build an exact Howard Hill replica you could not tell the difference in when strung that provides a HUGE gain in performance and no hand shock.... Funny thing is.... I did this 10 years ago and the HH cult wouldn't touch them.... I never took a single order for them... This was because of the unstrung profile wasn't straight.... I guess they use those things as spears on occasion.... :dunno: :dunno: The second reason was they shot the arrows too fast, and didn't have that "Thump" after the shot..... You know... that hand shock that requires holding the bow just right so you don't loose your dentures after the shot.... "You gotta learn how to shoot these bows." was the common response to hand shock issues.... Well.... i gave up trying to cater to that crowd, and took the offering off my website. I haven't built one in many years...
Getting back to core to glass ratio..... This is a key factor in a bows performance from one bow to the next.... a 60# bow vs a 30# bow has a large difference in core to glass ratio using the same thickness glass on each one. The 50-60# bow will always out perform the 30# at the same GPP arrow weight.
Trying to get two identical bows to perform the same at the same GPP arrow weight at different draw weights and draw lengths is very tough to do without matching core to glass ratio. Kirk
Post by: onetone on April 01, 2023, 03:47:49 PM
Post by: Longcruise on April 01, 2023, 05:58:51 PM
It's true. I've been shooting that style for a long time. Never had any issues with hand shock. Some shooters had HS with some of the same bows that i had none??? :dunno:
Post by: Jeff Freeman on April 02, 2023, 11:58:31 AM
Kirkl here the pictures you requested.
Post by: Jeff Freeman on April 02, 2023, 03:15:10 PM
I'm thinking shorten the riser from 17-1/2" to 15-1/2" might do it. Sticking with my same taper rate and glass thickness. JF
Post by: Kirkll on April 02, 2023, 03:30:21 PM
Same here Longcruise. I can shoot my longbows no problem. Others try them that shoot a medium to high grip. Recurve and they say it shocks their hand. I just laugh. I try to tell him but they don't get it.
Kirkl here the pictures you requested.
Oh i get it.... But you guys can have your teeth rattling low performance ASL bows. I'm not drinking that cool aid... :biglaugh:
As far as getting a smoother draw with lower PPI at longer draw lengths on a straight stick with low pre load at brace goes..... A longer power wedge pushing the working limb out further will help, but i think extra length is your only true option for a 30-32" draw length.
Here are the #001 Boot Hill Express pics...... This one has zero hand shock. BTW... i ran the power wedges up the belly ramps on this one, but modified it later on using a double ended PW on the back of the riser.... Much easier to lay up.
Post by: Jeff Freeman on April 02, 2023, 03:46:19 PM
Post by: Kirkll on April 02, 2023, 08:42:22 PM
Having only 3.1 PPI between 29-30” isn’t what I would call stacking… That really isn’t bad….. but if it jumps up to 4PPI from 30-32” , then you’ll need some changes. Good luck with that….
Post by: Jeff Freeman on April 02, 2023, 08:48:06 PM
Post by: Stagmitis on April 03, 2023, 08:28:41 AM
170`ish Fps @ 9 gpp with fingers on what appears to be a slight string follow is really good speed! Imagine throwing a little backset into it!
Post by: Jeff Freeman on April 03, 2023, 08:35:48 AM
Post by: Kirkll on April 04, 2023, 09:40:59 AM
of course you can’t use them as a spear anymore, and you will be shunned by the died in the wool ASL fan club… I wasn’t very popular at the Long Bow Safari at all. :biglaugh: :biglaugh: :laughing: :laughing:
Post by: Longcruise on April 04, 2023, 11:10:01 PM
Post by: Kirkll on April 06, 2023, 01:05:06 AM
Backset ASLs go way back. The longbow icon, Hill, made backset bows.
Yup…. But the vast majority of the HH fan clubs out there love their straight unstrung profile that kicks like a mule….. These guys would tell me, “You just need to learn how to grip it just right to shoot this type bow.”
And I’d tell them them them “ I already know the best way to grip one of those bows….. put it in someone else’s hand.”
Then I had a conversation about building a “String follow” bow for a guy…. I’m thinking why on earth would you purposely build a bow with string follow? I still cant wrap my head around that one…. :dunno: :dunno:
it don’t make sense to add more limb mass just so your unstrung bow has a
reverse reflex…. What’s the point?