Hill style build need help

[Danjoseph]

You might reconsider the limb length differential.   Hill style bows with a shortened limb are known,  but with the precision tapers we use now.

Longcruise thanks for your reply...but I didn't understand your quote above about why I should reduce the length differential could you please clarify...and yes thanks for the tip about reducing taper rate if I taper the glass I definitely need to take that into account.
Regards, Dan.

[Danjoseph]

hill style longbow specs...
Taking glass taper into consideration...all else the same...

ntn 66
Riser 14
Draw Weight  50 to 55#@28"
Forward Taper 0.0056 including glass taper
Fade Width 1.125
nock width 0.49
stack at butt 0.54
Upper Limb Length 26.875
Lower Limb Length 25.125
Upper Fade Depth 0.505
Lower Fade Depth 0.495
Riser Offset 0.875
Glass Percentage Fades 19.14
Glass Percentage Tips 22.57

Taper the fiberglass on back and belly so that the fiberglass tips are at about .04" thick to reduce fiberglass to wood ratio at the tips to about 22%

All suggestions are welcome...
Regards, Dan.

[Stagmitis]

Plan one
* Your best option!-

ntn 66
Youre on the cusp-  66" will give you a shallower string angle W/ better accuracy. Wanna get fancy? go 65"

Riser 14
* Perfect!

Draw Weight  50 to 55#@28"
* Okie dokie!

Forward Taper 0.005
* You can go to .006 without a whippy ended bow at that bow length and riser combo-Also futher reduces limb mass. I would also add a 3" .40 glass tip wedge.

Fade Width 1.125
* I like mine narrower but string alignment becomes a challenge the narrower you go. Stay with that width for your 1st

nock width 0.4375
* Too narrow-you will lose stabilty in outer third of limb-I would go .470- .490  for your 1st bow if you must go below .500 

stack at butt 0.530
I am assuming glass+core


Upper Limb Length 26.875
Lower Limb Length 25.125
*1.75" or even 2.00" shorter lower limb works. I like 1.5

Upper Fade Depth 0.499
Lower Fade Depth 0.491
????????????????

Riser Offset 0.875
* Just make ramps even

Tip Depth 0.365
* It is what it is relative to tapers/glass

Glass Percentage Fades 20.20
Glass Percentage Tips 27.39
* If you want a whippy ended bow certainly do this! Rather go .50 belly .43  back to reduce limb mass-adjust stack accordingly.

I am sure all of us would love to see a build along! Aslo what about pics of your KennyM R&D bow you were going to post? 

[Longcruise]

Longcruise thanks for your reply...but I didn't understand your quote above about why I should reduce the length differential could you please clarify...and yes thanks for the tip about reducing taper rate if I taper the glass I definitely need to take that into account.
Regards, Dan.

I'm suggesting that both limbs be the same length.   There is no advantage to building in that difference.   If anything,  it makes tillering unnecessarily complicated.  Also,  the lower limb will be strained more than the upper which could result in the lower limb taking more set over time. 

Obviously,  stagmitis differs on that.   Probably many others do as well so read and think it through for yourself.  I certainly don't have a monopoly on facts. 

[algstick]

Dan,
Don't let the shorter lower limb confuse things.
build your riser symmetrical and place the shelf of the riser 1-1/4" to 1-1/2" above the centerline of the bow . This will have you shooting the arrow close to the centerline of the bow as possible and will create a built-in positive tiller at the same time. you should have a lower limb that is 1-1/4" to 1-1/2" shorter than upper limb as measured from fadeout to nock. this will minimize adjustments for tiller later. if you will notice the dimensions that were provided to you indicate this layout. I would save tapering the fiberglass for another build, you will have enough to deal with keeping the string tracking down the centerline of the bow.
this is certainly not the only way to layout a bow, just my 2 cents. Good luck and don't kid yourself,,,,, this will not be your last bow build, LOL

[algstick]

correction the lower limb will come out 3/4" to 1" shorter than the upper limb. My bad. (I never measure that, just lay the bow out like I described)

[Danjoseph]

Stagmitis thanks for your reply.....yes I will go with the 66" ntn plan but I just need to clarify the following...

[Riser Offset 0.875
* Just make ramps even

And you also mentioned that if I want whippy tips to do the following

    Glass Percentage Fades 20.20
Glass Percentage Tips 27.39
* If you want a whippy ended bow certainly do this!   

I didn't understand.... what will give me a whip ended bow is it the glass/wood ratio that is too much at 27% at the tips or is tapering the glass a problem....please clarify.

I would have posted pics of my rd bow but someone said to start another thread for that, moreover i don't want this thread to deviate to rd bows..so I'll start another thread and post the pics there In a couple of days...
Regards, Dan.

[Danjoseph]

Longcruise... I have built bows with equal limbs with the riser in the center...I don't want to do that..I want to build a Howard Hill style  Longbow....and as far as I know it's built like that...
I want to see and experience for myself if it does improve my accuracy because with my rd bows if I'm a bit out of form or the arrow is not perfectly tuned I have quit a few fliers... With a HHS bow with a bit of string follow I hope to end up with a nice shooting bow like my boo backed bows that I made years ago ..by the way those were equall length limbs with riser placed in the center...
Regards, Dan.

[Danjoseph]

Algstick thanks for your reply....yeah I like the idea of building an asymmetrical longbow...so I'll do it that way ..thanks for your suggestions,...
Even stagmitis says he uses 1.5" longer top limb. So I'm going to revise my plan...and make it 1.25 to 1.5" longer
Regards, Dan.

[Longcruise]

Longcruise... I have built bows with equal limbs with the riser in the center...I don't want to do that..I want to build a Howard Hill style  Longbow....and as far as I know it's built like that...
I want to see and experience for myself if it does improve my accuracy because with my rd bows if I'm a bit out of form or the arrow is not perfectly tuned I have quit a few fliers... With a HHS bow with a bit of string follow I hope to end up with a nice shooting bow like my boo backed bows that I made years ago ..by the way those were equall length limbs with riser placed in the center...
Regards, Dan.

I'm confused as to how you are measuring limb length.  Are you saying that the limbs are the same length from the end of the fadeouts to the nocks?  If so, we are talking about the same thing.  If you use an asymmetrical riser to get the arrow rest closer to center and then measuring limb length from the arrow rest to the string nocks then I would not expect you will have any problems.   IOW, are you building limbs with unequal working length (fades to nocks)?

[Danjoseph]

Longcruise all the measurements I gave above are lb lengths from fade to nocks...earlier I built them the same length and with symmetrical risers too

[Danjoseph]

Longcruise...come to think of it you have a nice point about using an asymmetrical riser... because the reason I want to build the top limb longer is to get the shelf/nock point closer to bow center. This way I can do just that and aslo keep the limbs equal length from fades to nocks...
So.... there's definitely no such thing as "I will build one bow " there's always another on the horizon...

[Stagmitis]

Stagmitis thanks for your reply.....yes I will go with the 66" ntn plan but I just need to clarify the following...

[Riser Offset 0.875
* Just make ramps even

And you also mentioned that if I want whippy tips to do the following

    Glass Percentage Fades 20.20
Glass Percentage Tips 27.39
* If you want a whippy ended bow certainly do this!   

I didn't understand.... what will give me a whip ended bow is it the glass/wood ratio that is too much at 27% at the tips or is tapering the glass a problem....please clarify.

I would have posted pics of my rd bow but someone said to start another thread for that, moreover i don't want this thread to deviate to rd bows..so I'll start another thread and post the pics there In a couple of days...
Regards, Dan.

The effect of tapering your glass towards the tip is no different than increasing your core tapers to who knows what maybe .007+. You will make it whippy(bend more) and you will lose performance. You want a stiff tip. There are other things you can do to lighten the tip while keeping it stiff...Tapering glass is not one of them...Dont ask how I know

By even ramps I meant build a symmetrical riser....

Longcruise, the shorter lower limb not only creates a more balanced bow (if held in optimum bone to bone alignment) but also increases preload at brace. You will get more performance and since youre building on a straight form you need as much as you can get.

If you know how to tiller a bow then it doesnt matter if you have an even limbed bow or one with a shorter limb.

Like Algstick said your biggest challenge will be string alignment. Thats the sole reason many shoot Hill bows and complain about their dentures 

[jsweka]

This is getting too complicated for me.  Maybe I should quit building laminated longbows and just start whittling on sticks.   

[Danjoseph]

Stagmitis thanks for the explanation I appreciate it very much... earlier it totally slipped my mind about the taper rate changing due to tapering the glass..however after reading your post I've decided not to take a chance with this bow and fiddle with the glass but to go with thinner glass 0.043" on the back and 0.05 on the belly...
In addition I will also go with your advice and leave  the tips wider at about 0.5....if I do  decide to go with my earlier plan on thinner tips I'll use a tip wedge...but maybe not since I've never used tip wedges before and I'm afraid of it slipping out of place.
Regards, Dan.

[Danjoseph]

Jsweka..I did start off whittling sticks and progressed to making glass bows..... whittling sticks gives you a chance to see where you are going with the tiller, but with glass bows you need to be close to final tiller as there's not much to do once the bow is glued up....hence all these questions...
If I was a rich man I could just do whatever I please and learn from my mistakes....
Regards, Dan

[Danjoseph]

Jsweka could you please tell me what difference did changing From .002"/" taper to .005"/" make to your total stack for the same drawweight all else being the same....
Regards, Dan.

[jsweka]

Increased it. I’d have to find my old notes somewhere to tell you exactly how much.

If you’re worried about money and only have one shot at getting exactly what you want, you’re probably better off having a professional build you one or buying a used one when you see one pop up in the classifieds somewhere.

[Danjoseph]

Increased it. I’d have to find my old notes somewhere to tell you exactly how much.

Jsweka thanks for your reply.. I know it definitely increased your stack....I was hopefull that you could tell me by how much ...
Regards, Dan

[Overspined]

I’m cracking up here...  crank out a bow, make adjustments and make another. And you’ll probably hit your stride on another then they only get better from there...it takes a whole lotta many builds to crank a bow out that’ll rival these guys doing it for a living. The bow is the easiest part of the equation. Getting arrows tuned and your shooting in line is a far bigger undertaking..

Jsweka said it, if you just want to build one, have someone else do it.

Heck just the finishing process alone takes a lot of practice unless someone is showing you how.