Author Topic: I removed too much wood  (Read 2649 times)

0 Members and 2 Guests are viewing this topic.

Offline sleek

  • Member
  • Posts: 6,689
I removed too much wood
« on: March 21, 2013, 05:30:12 pm »
I removed too much wood of the tips of an Osage recurve. Now the tips flatten out straight at full draw. I know working recurves are common, but I want these to be static. Also, I am not quite at my draw weight yet, I need 40 lbs. So, I want to laminate brazillian cherry on the belly side. I was also thinking I could use some horn. After the lam is done, I was going to narrow it to loose some mass, without making it too narrow as to bend again.

So here is my question, When making bending tips rigid, do you need a power lam like when you laminate a riser on a bending handle? If so, how would that be done? What would be the best power lam, the brazilian cherry or the horn? I really need the brazilian cherry to show as much as possiable so I was thinking of a thin horn power lam?
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline bow101

  • Member
  • Posts: 2,235
Re: I removed too much wood
« Reply #1 on: March 21, 2013, 05:46:04 pm »
Ummmmm if you want to stiffen up the tips with brazilian cherry, I say go for it. But why ad a power lam..? ::)
"The privilege of a lifetime is being who you are."  Joseph Campbell

Offline k-hat

  • Member
  • Posts: 1,058
Re: I removed too much wood
« Reply #2 on: March 21, 2013, 06:07:20 pm »
Don't think all that is necessary, just a thick enough belly lam to replace the wood you removed should be fine.  I've seen several round here with a belly lam like that to reinforce the static tips.

Offline bubby

  • Member
  • Posts: 11,054
Re: I removed too much wood
« Reply #3 on: March 21, 2013, 06:14:20 pm »
yeah just steam the cherry and get it bent then glue it up
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline sleek

  • Member
  • Posts: 6,689
Re: I removed too much wood
« Reply #4 on: March 21, 2013, 10:36:38 pm »
Well, thats what I will do then. Just wasnt sure if I needed one or not, cause for some reason bending handles need one, reckoned bending tips might too....
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline missilemaster

  • Member
  • Posts: 1,172
Re: I removed too much wood
« Reply #5 on: March 21, 2013, 11:20:09 pm »
You dont need a power lam, just keep the wood thick.
All men die,  few men ever really live.

Real men love Jesus.

mikekeswick

  • Guest
Re: I removed too much wood
« Reply #6 on: March 22, 2013, 05:13:21 am »
Horn has very low bend resistance so would be my last choice. Brazilian cherry will be fun to bend.....
I'd use osage. Remember to double the stiffness increasde the thickness by an 1/8th

Offline sleek

  • Member
  • Posts: 6,689
Re: I removed too much wood
« Reply #7 on: March 22, 2013, 05:41:30 am »
Thanks bud...
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline RBLusthaus

  • Member
  • Posts: 753
Re: I removed too much wood
« Reply #8 on: March 22, 2013, 12:10:38 pm »
Just a thought - - since you are gluing anyway, you might consider adding a string bridge also.  I always wanted to do one of those, never have.  Love the way they look. 

Russ


Offline Prarie Bowyer

  • Member
  • Posts: 1,599
Re: I removed too much wood
« Reply #9 on: March 22, 2013, 02:13:06 pm »
I'd cut a belly lam flat and straight and bend and glue it on.

Offline sleek

  • Member
  • Posts: 6,689
Re: I removed too much wood
« Reply #10 on: March 24, 2013, 07:47:47 pm »
Well, where I glued on the single belly lam, and feathered it into the belly, it is buckeling when I bend it. I had to trim the feathered off portion, and re feather it. Also, the recurve straightened out again, and I can see where the glue line has shifted in shear forces. Its been almost 18 hours sense glue up, what am I doing wrong?
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline Marc St Louis

  • Administrator
  • Member
  • Posts: 7,869
  • Keep it flexible
    • Marc's Bows and Arrows
Re: I removed too much wood
« Reply #11 on: March 24, 2013, 08:00:51 pm »
I would have used a lower density wood like Black Cherry.  The feathering should have been done after.  The Jatoba has high tension strength so it is trying to straighten the recurve in the Osage. 

What you could have done is clamp the recurves in a form to hold them securely and apply some dry heat to them, more or less heat-treat them, then glue a thin lam of BC to them.  I've done this many times when I have had a recurve splinter while steam bending.  Works every time.
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline sleek

  • Member
  • Posts: 6,689
Re: I removed too much wood
« Reply #12 on: March 24, 2013, 08:28:46 pm »
Hi Marc, thanks very much for replying. I did the feathering after the glue was dried. I actually cut the Jatoba into the shape of the recurve, put the bow in the recurve form to get the recurve bend right, and then glued it on with TBIII. This is causing me some grief because the tips are coming out, I am loosing draw weight. I need 40 and have 37.

Is the reason you would black cherry only because of the mass? Does Jatoba have a problem with being underlays? Now that it seems the glue line has failed, I will need to remove the underlays, and make new ones. I will try it your way this time. I will be using the Jatoba though.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline Marc St Louis

  • Administrator
  • Member
  • Posts: 7,869
  • Keep it flexible
    • Marc's Bows and Arrows
Re: I removed too much wood
« Reply #13 on: March 24, 2013, 08:53:04 pm »
Yes I would use BC because of the mass.  Because the glue line adds strength of itself you don't need to add much thickness to increase the strength of the recurves.  So far as I know the Jatoba should work as well as any other wood.  I'm not sure why the recurves are pulling out with the overlay glued on, that's never happened to me.  Did you sand both surfaces before gluing?
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline Josh B

  • Member
  • Posts: 3,741
Re: I removed too much wood
« Reply #14 on: March 24, 2013, 08:53:45 pm »
Man Sleek, I feel your pain!  I'd hate to admit how many times I've done the same thing.  I usually use the same wood for the overlay or something lighter such as hackberry or elm.  I've never messed with jatoba, so I'm no help there.  I do make sure the patch is straight grained and heat bend it into just a little tighter bend than the curve before gluing on.  Good luck!  Josh