Author Topic: Building with a twisted Martin Hawk blank  (Read 5346 times)

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ScottB

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Building with a twisted Martin Hawk blank
« on: January 08, 2008, 05:59:43 pm »
Hello:
Hello, Folks,
I'm brand new to the board and have spent some time searching for this here, but may not know enough to have done so thoroughly, but my situation is this:
I bought a Martin Hawk longbow blank to finish from a friend who got it a few years ago -- 33 pound, 66", yellow birch and hickory.  I want to finish it for my daughter to shoot at our rendezvous competitions.  The limbs are severely twisted -- enough to where sighting down the limbs with it strung and lining up the string as close to center on the bottom limb as possible places the string on the top limb completely off the limb's line of sight.  The limbs are twisted in opposite directions.

I've never built a bow of any sort -- don't even know the terminology to use -- but have shot competitively in archery for more than 30 years, so I'll understand what you're talking about (I hope).  My daughter has competed for several years as well in 3-D shoots, so acuracy is a bit of an issue, if it can be achieved with this bow.

Is there a way to get the twist out of the limbs?  The bow seems inexpensive, but it looks like a fun project for a father/daughter to work on -- would hate to have at it for nothing.
Thanks so much for any help,
Scott Brockwell

Offline mullet

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  • Eddie Parker
Re: Building with a twisted Martin Hawk blank
« Reply #1 on: January 08, 2008, 06:07:16 pm »
   Scott,Can you post some pictures? It will give everybody an idea of what you are working with. It might not be as bad as you think. But if it is, I know we can walk you through straightening it. It's not that hard to do.
Lakeland, Florida
 If you have to pull the trigger, is it really archery?

Offline tom sawyer

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Re: Building with a twisted Martin Hawk blank
« Reply #2 on: January 08, 2008, 06:14:12 pm »
Those are backed with fiberglass right?  Or is it glass on both back and belly?  You should be able to heat sections of the limb with hot water or a blowdryer, and "bump" them straight by twisting slightly past center.  Get it good and hot, where it feels very warm to the touch.  Then twist in the directoin opposite the original twist, just past where you want it to finish (it always springs back a bit).  Hold it there until it cools, several minutes.

But I warn you, too much heat and you can get delamination.  Hot water sort of prevents you from overheating, but I'd let the limbs dry out for awhile after doing this if you go this route.
Lennie
Hannibal, MO

Offline Traxx

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Re: Building with a twisted Martin Hawk blank
« Reply #3 on: January 08, 2008, 07:34:40 pm »
The early Hawks,were wood backed bows.Just before they stopped makeing them,they put a glass laminate in the bow.

Offline DanaM

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Re: Building with a twisted Martin Hawk blank
« Reply #4 on: January 08, 2008, 07:51:38 pm »
Hi scott I can't offer you any advice but I can say welcome to P.A. Lots of good folks here
with so much knowledge to share so I think you made a good choice. Keep us informed on how it works out.
Father & daughter projects are always special.
"Prosperity is a way of living and thinking, and not just money or things. Poverty is a way of living and thinking, and not just a lack of money or things."

Manistique, MI

Offline mullet

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Re: Building with a twisted Martin Hawk blank
« Reply #5 on: January 08, 2008, 08:29:20 pm »
   Didn't know it was glass backed,but what Lennie said will work. Another way is to get a strong friend and both grab a limb and twist in the direction you need to straighten the limbs but go a little farther. Hold for a few seconds and then put the bow away strung backwards. I've done this on old recurves with good success.
Lakeland, Florida
 If you have to pull the trigger, is it really archery?

ScottB

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Re: Building with a twisted Martin Hawk blank
« Reply #6 on: January 08, 2008, 10:53:37 pm »
You guys are fast!  Thanks for all the replies so far, and for making me feel welcome.  I guess all folks "primitive" are generally good people.  I shoot and build a few flintlocks and make primitive knives, and the folks involved in those arts are the same way.

  The bow does not have any visible glass in it -- looks like two distinct laminations of wood.  I'm not real adept with computers, so I'm not sure how to load photos here, but sounds like you're picturing what I'm talking about with the twist.  I can try heat -- I have a heat gun and can control it pretty well. 

How do I know when I'm getting too hot short of watching the limbs come apart?  Almost too hot to touch, or considerably less?  Do I do one limb at a time, or the whole deal?   And maybe more importantly, do I finish the bow (sand, stain, shape final contours) first; will that effect the twist either way?  Or do I attempt to get the majority of the twist out first, and then do the rest?

One last thing, if I may:  is there a tutorial somewhere on backing with snake skins?  I've tanned all the copperheads that choose death on my farm, and think that could dress the bow up some.

Thanks again,
Scott

Offline Justin Snyder

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Re: Building with a twisted Martin Hawk blank
« Reply #7 on: January 08, 2008, 10:59:13 pm »
Scott, if you read Gordons Hazelnut D-bow buildalong on the buildalong page you will find that he covers putting snakeskins on the back of the bow.  Here is the link to the tutorial version of Gordons buildalong.  http://www.primitivearcher.com/smf/index.php/topic,4815.0.html  Justin
Everything happens for a reason, sometimes the reason is you made a bad decision.


SW Utah

Offline Pat B

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Re: Building with a twisted Martin Hawk blank
« Reply #8 on: January 09, 2008, 12:35:03 am »
Without knowing what type of glue that was used I wouldn't heat it up too much. I have never tried to straighten a backed bow before so thats the best info I can give.    Pat
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline Traxx

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Re: Building with a twisted Martin Hawk blank
« Reply #9 on: January 09, 2008, 03:07:07 am »
ScottB,
The thin glass laminate in the Hawks were dark and obvious.Yours is one of the older all wood bows.

Offline tom sawyer

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Re: Building with a twisted Martin Hawk blank
« Reply #10 on: January 09, 2008, 10:39:26 am »
I'd approach the heating carefully.  Heat it just warm and try bumping it straight.  If it doesn't hold, heat a little warmer on the next try.  I've heated glass recurves to where the limb was pretty hot to the touch, and got good results.  It doesn't take long to get those thin limbs hot enough, especially using a heatgun (which is what I used.)  I suppose they're using Smooth-On for glue and that is usually cured at elevated temps so it should withstand a certain amouont of heating.

Of course we respond quickly, we're supposed to be working.
Lennie
Hannibal, MO

ScottB

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Re: Building with a twisted Martin Hawk blank
« Reply #11 on: January 09, 2008, 05:44:30 pm »
Again, thanks to all of you for your kind help.  The gentleman who built the snake-backed bow in the tutorial did some incredible work, and it's inspired me to work harder on this bow.  Thanks again.

Scott

Offline mullet

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  • Eddie Parker
Re: Building with a twisted Martin Hawk blank
« Reply #12 on: January 09, 2008, 09:20:59 pm »
  Scott ,like Lennie said I'd go easy on the heat. I think I'd try to remove as much of the twist as possible tillering the bow. You can remove a lot of it that way and possibly not have to you heat. Site down the bow while it is strung from tip to tip looking at the belly.If it is close to the side you want to shoot on sometimes you can deepen a nock groove and move the string over.
Lakeland, Florida
 If you have to pull the trigger, is it really archery?