Taper rate & Riser lenght Hill style bow ?

[PV]

Picked up a hot box and a straight inner tube form from a friend.Been collecting dust in his shop for the last 20 years.

I've never built a straight or "D" glass bow before and I'm lookng for a starting point for a:
 
66" NTN, Aboo lams for some string follow, hopefully not too much,straight side taper fades to nocks.

Suggestions on taper rate and riser lenght greatly apprieciated

Paul

[jsweka]

In the ones I've built, I've used 3 parallel lams and one 0.002 taper. 16" riser. My form is perfectly straight but after stringing and shooting the bow for a while I end up with just a touch of string follow.  It's really not noticeable unless you hold the bow up to your eye and sight down the edge of the limbs.

[PV]

Thanks John.. What material are you using for core lams?

[bjansen]

On my hill I used .005 per inch taper, 16" riser, 66" NTN.  1.05" at the fades down to slightly less than 1/2" right before the nocks.  The butt thickness of my lamination stack was .590" and achieved 57# @ 28".  My form has 3/4" of backset in it..and if you used a straight form I am guessing this same lamination stack would get you 3# less (just a guess).

Good luck

[PV]

Thats a fair bit of taper Brad.How far out from the fades do your limb start bending ?

[bjansen]

Well, right after the fade I suppose.  It is not a whip tillered bow that is for sure, and in fact the real Hill's that I have seen use the same taper rate. I put a small tip wedge in the bow, but that only extends 1.5" past the nock.

[kennym]

1.05 is a fairly narrow bow ,.005 will work well there.

The way I see it, with less width taper from fades to end, the more lam taper you can use.

Disclaimer  >>>>------------------>

I'm not a hill style guy.  

[PV]

Never been a Hill guy either Kenny. Want to build at least one. Stopped at the local tire shop yesterday and picked up some used truck tubes. Cut some big bands and some long strips.
Went with 4 .001 tapers (Aboo)and .043 black glass for a stack of .410,16" riser.Binghams chart says this will yeild a #55 bow at 68 "and 17" riser
Prep and glue up was a breese compared to my R/D bows with an air hose.
Put the bow into cook at a lower heat in my new to me hot box.Went to shut the oven off and take a peek before bed....
 
 
   The bands held up fine but a few of the long strips blew out on the fade out ramp. Live and learn.  As this was the last of my aboo and a few more projects to finish before I leave for warmer(hopefully) weather Saturday for some hog hunting this will be going on the back burner for a while.Maybe forever.......

[Jason Jelinek]

I would recommend at least 3 tapers of .002"/".  I think 4 tapers of .002"/" would be better.  The more the thickness taper the more the outer limbs bend.  If you have a 66-70" bow with a 14-18" riser you should have a pretty fast bow that doesn't have a lot of handshock.

If you have a lot of thickness taper with a short bow and a longer riser, you'll start seeing the bow stack.

[rpembert]

Howard Hill's bows had a TOTAL taper of .001. He used to acually shave it down like a self bow, working it down by hand! His bows were generally 69 inches long. His AMO on his bows were 66 1/4. Weird I know. Now the risers as Jerry Hill explaind to me were no longer than 14". I build mine to 13 3/4" which is what Jerry built his to as per Howards instructions. Howard never put any wood up on top of the riser or tip overlays. That is the way John Shultz built his bows and the way Craig builds his. All he had on the riser was fibreglass or some other material and his lams were behind the riser. Howard made them simple for use not for looks.

Thanks and good to be back,
Joshua

[jsweka]

PV - I've used actionboo and hard maple for the two center lams.  For the outer lams under clear glass, I've used red elm, curly maple, osage, and cherry.

[PV]

Thanks John.

 what people are using for a taper varies considerably. I thought it would be fairly close as the side profile is basicly the same from bow to bow.

[eflanders]

Does anyone have genuine information on Hill's early non-glass bows?  I would love to get some accurate data accordingly!

[Apex Predator]

The Hills that I have handled have lots of taper.  They have to because of the narrow width profile.  It has to taper somewhere!  I build mine with four .001 tapers, and like them.