Building a Hill Style Longbow, Problem

[Mike Taylor2]

I want to build a Hill Style Longbow for my Uncle, he's 6'6" and draws 31". My first attempt made weight at 28" but won't draw beyond 29" without jumping up 10lbs in weight. Talk about stacking.
This is a straight limbed longbow, narrow like a Hill and 72" long.

I suspect I have the incorrect ratio of tapers to parallels. I want the bow to come out to about 55lbs @ 31" draw.

Can anyone help tell me what I did wrong and how to fix it. I used 4 lams, 2 parallel & 2 with a .001/in. taper.

Thanks in advance.

[bjansen]

Lets see some full draw pics of that bow...might help

If I were to build that 72" bow, I would have used a:
- 14" riser
-.006 total taper per inch
- total stack of .525 including the glass
-1.10" wide at the fades to .500" tips

I know it is hard figuring out the long draws though...

[2treks]

I woulod think you need about double that taper,or more.
Brian is looking pretty good.

[Mike Taylor2]

It almost has to be the taper.  I had:
16" riser
.002/inch taper
Totalstack of .530
1.05 wide at fades to .5" tips

I also put in a .050 wedge in the tip to keep the bow tip from bending.

Any thoughts on tip wedges????

[Mike Taylor2]

What overall taper do you guys use in a Hill style for 28-29" drawlength.

[jsweka]

In a 68" bow for a 28" draw, I use a total of 0.002 taper/inch.

I'm pondering the advice from others above about going with more taper for a longer draw length.  In my thinking, wouldn't that cause the outer portions of the limbs to flex more, and the inner portions of the limbs to flex less upon draw.  Thus, your string angle would approach 90 degrees sooner with more taper and once you hit 90, that's when you start getting a lot of stack.  Or am I thinking about this all wrong?

[Mike Taylor2]

That's what I was thinking jsweka, in fact I almost put the lams in backwards with the thick part toward the tips.

I'm here to tell you with a .002/in overall a 72" bow stacks hard at 29" so there is something we don't understand.

[bamboo]

mike--i think you made the riser/limb butts way too narrow for a.002 taper[bending way too close to the riser and causing stack]--the hill would have .006 taper w/narrow riser/limb butts--bending further out from the riser

[monterey]

Originally posted by Mike Taylor2:
What overall taper do you guys use in a Hill style for 28-29" drawlength.

For all of mine I've used an 18" riser, .002 taper (one set of tapers), three parralels plus glass.  Width at fades has ranged from 1 1/4 to 1 3/8.  No tip wedges.

Four have had a mild back set starting 4" from the fades and ending in about 1 1/4" with the backset being almost a perfect circle radius.  Two are plumb flat.  The four with backset range from 66 to 68 inch ntn.  The two flat ones are 66 and 68 inch ntn.

Limb profile has been a very gradual taper in the first 7 to 9 inches from the fades and then a slightly faster taper to the tips.  Tip widths have ranged from 5/16 to 3/8.  None of these six have had an identical limb profile with some being a bit faster taper than others.

The reason for the TMI above       Is to preface the fact that  all  of these bows have stackless draws out to 30 and 31".

I'm befuddled.   :confused:  

I agree that increasing the degree of taper in the tapers you are using will cause the limb tips to come more quickly into a 90 deg angle and might increase stack.

The only thing that comes to mind is that maybe your tapers had way more taper than you thought they had???

[kennym]

Originally posted by bamboo:
mike--i think you made the riser/limb butts way too narrow for a.002 taper[bending way too close to the riser and causing stack]--the hill would have .006 taper w/narrow riser/limb butts--bending further out from the riser

My thought too.

The narrower the bow at fades, the more taper you can use, the limb has to have so much taper to bend the way you want it. you get lots more edge taper  going from, say, 1.5 to .5 than from 1.05 to .5

[monterey]

Kenny, I think you are onto something there.  I do think that if he tapered the limbs a bit faster and ended with a very narrow pin nock that it could work.

[monterey]

I dusted off another that goes way back.  This one is 68ntn, 18" riser, three parralels and one taper at .002.  Width at fades is 1 1/16",  six inches from the fades it is 1" wide,  twelve inches from the fades it is 3/4" wide and then 7/16" at the nocks.  FWIW, it has about 3/4" string follow.

Here is an FD curve for this bow.  It's a bit ragged using the bathroom scale.    

 

[kennym]

We really need a pic at full draw....

[Mike Taylor2]

I'll see if I can come up with a picture tomorrow.  

Thanks everyone for their help and ideas.  I tried on the other un-named site and either they knew nothing or weren't willing to help.  

This site is great.

[bamboo]

its definatly bending too much at the fades--
a 72" bow w/a .002 taper would easily draw 31"
i've got guys that are drawing 30"+ w/64"[.002 tapers x 1.25"fades]so a 72" should be smooth to 31"--we need full draw pictures too be sure--mike i pesonaly like the .002 taper longbow design---its a better[IMO]shot feel and bit faster--and stack is something even my toughest critics haven't mentioned --montereys force draw gragh shows the gain as smooth right off the  gragh

[Mike Taylor2]

Here are a few pictures and some updates.  Definately too much bend at the fades, Looks like the 8" wedge was a bad idea also.

The bow is actually:
16" Riser
1 1/8th wide at fades
5/8ths at tips   will be 1/2 when finished
Total stack of .530
4 lams-  2 Parallel... 2 lams .001/inch taper
8" wedge in tip-starts at .050 and tapers


 

 

[kennym]

The left limb looks  fairly good to me, the right is bending a little much at the fade, or the pic is making it look like it.

Overall, it looks pretty good tho. When you get the limbs skinnied down at tips, it may help you a bit.

Have you checked weight every inch out to the desired draw length to see where it starts gaining faster?

All bows feel like they stack to me after about 55# LOL

[Mike Taylor2]

Everything looks fine to 28".  The picture is at 28".

From 28" to 29" the bow gains 8 pounds.  Afraid to pull it any further than that.

[bamboo]

#8's huh?!?!??kenny's right --it doesn't look bad--they all feel a little wierd at first!narrow the tips to a 1/2"--but start the taper [narrowing] 12" in from the tips--then i would trap it starting 2in outside the fades and round it more pronounced as i moved out towards the tips--also try sanding the glass on the outer limbs to try and get more outer limb bending--it ain't over yet!!go easy and try not to cause any more inboard limb bending--i think you still have a shooter in there

[2treks]

Notice what the string loop is doing in the nock groove,or at the belly side of the nock groove. That is not helping the stacking problem at all.Opening the top of the groove may help some.
The outter third of your limb looks stiff,and as Kenny said,after you skinny the tips up, that might help as well.
Most hill bows will use a tip wedge about 2-3 inches below the nock. 8" seems long for this bow. Also,I would run some sandpaperon the edges of your limbs to prevent the splinters from lifting.That can make a guy cry,so I've been told.
Hope this helps. nice looking glue lines on that wedge.

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