Primitive Archer

Main Discussion Area => Bows => Topic started by: Swamp Thang on November 15, 2017, 06:15:09 pm

Title: Is it worth it
Post by: Swamp Thang on November 15, 2017, 06:15:09 pm
Sinew backed with a bamboo belly.
Title: Re: Is it worth it
Post by: bradsmith2010 on November 15, 2017, 06:22:42 pm
I never tried that,, sounds interesting
Title: Re: Is it worth it
Post by: PatM on November 15, 2017, 07:23:39 pm
Been done many times.  Because it's a good combo. Heat treated high quality bamboo surpasses wood in compression abilities.
Title: Re: Is it worth it
Post by: Swamp Thang on November 15, 2017, 10:09:34 pm
Been done many times.  Because it's a good combo. Heat treated high quality bamboo surpasses wood in compression abilities.

Sweet!!! What about for a 46" D bow
Title: Re: Is it worth it
Post by: stuckinthemud on November 16, 2017, 04:58:35 am
I think I read that the bamboo needs to be charred black when you heat treat it??
Title: Re: Is it worth it
Post by: Hamish on November 16, 2017, 06:31:57 pm
I think the charred black look is overkill, from the days before heatguns, where people used blowtorch set ups for tempering. Not necessary to go that far and you still gets the performance results.
 If you are not already aware you only temper the belly lams, not the backing.
Title: Re: Is it worth it
Post by: Swamp Thang on November 16, 2017, 06:50:03 pm
Haha yeah I'm aware
Title: Re: Is it worth it
Post by: Swamp Thang on November 16, 2017, 06:52:44 pm
I am wondering I have harvested 8 deer leg sinew plus some from the butchering how much do I need for a bow 48" long 1.75" wide
Title: Re: Is it worth it
Post by: Swamp Thang on November 16, 2017, 07:10:10 pm
Also how much is to much sinew, soft wood bow with boo belly
Title: Re: Is it worth it
Post by: Swamp Thang on November 29, 2017, 07:14:12 pm
Slaughtered and quartered a steer snagged me some sinew and the hide been scraping for three days now but got some thick long sinew more than enough for 2 more layers of sinew plus a string... I hope
Title: Re: Is it worth it
Post by: Swamp Thang on December 07, 2017, 03:49:20 pm
Okay question sinew backed this bow and within a couple days I've noticed it's deflexing not relfexing what did I do wrong you think?
Title: Re: Is it worth it
Post by: Swamp Thang on December 07, 2017, 04:05:27 pm
Also how might I rectify
Title: Re: Is it worth it
Post by: willie on December 07, 2017, 04:15:21 pm
if you have another slat or scrap of that bamboo, you might try putting a moist cloth or something on the same side as the sinew was applied. look to see if the moisture creates the same effect. my guess is that it will come around the way it's supposed to when it gets a bit drier. did you toast the bamboo before applying he sinew?
Title: Re: Is it worth it
Post by: Swamp Thang on December 07, 2017, 04:37:03 pm
Haven't put the bamboo on yet looking for the right piece it hard to find the larger sizes down here
Title: Re: Is it worth it
Post by: Swamp Thang on December 07, 2017, 04:38:37 pm
Pretty sure it is the moster that's got in the wood but I'll not sure.
Title: Re: Is it worth it
Post by: DuBois on December 07, 2017, 04:38:49 pm
I had an ERC bow go into deflex after sinew and I think it was due to moisture being absorbed by the dry wood and swelling the cells on the back but not the belly. I waited a while to see what it would do and it did start to regain reflex as it cured. I then tied it into reflex to help it along. Still have it-one of my favorites.
Title: Re: Is it worth it
Post by: bubby on December 07, 2017, 05:40:59 pm
Did you size the back of the bow before sinewing? Besides helping with adhesion it also keep moisture transfer down, i pull mine into reflex and then sinew, then after it dries i pull it into more reflex and add sinew
Title: Re: Is it worth it
Post by: DuBois on December 07, 2017, 06:38:12 pm
Good point Bubby,
I did size it but may not have waited long before starting sinew. Can't remember for sure but that's probably the case. It was early in my sinew attempts. I do like you now and pull some reflex before starting sinew.
Title: Re: Is it worth it
Post by: Swamp Thang on December 07, 2017, 11:34:39 pm
Wow so wait and see huh? Then reserve string when I resinew?
Title: Re: Is it worth it
Post by: willie on December 08, 2017, 01:38:19 am
I guess what I did not understand from the opening post, is that you are sinewing the core before adding the bamboo belly?

so the idea of pulling  the bow into reflex while sinewing, I guess, is to make the sinew work harder to get to brace. I can see that as being a good thing because sinew can stretch a lot and take it.

But do you really want to wait until the bow has a lot of reflex before you add the bamboo? wouldn't that make the boo take set sooner?
or is there a plan to perhaps put it on a caul in some deflex, or at least, less reflex, to do the final glue up the boo belly?
Title: Re: Is it worth it
Post by: Swamp Thang on December 08, 2017, 10:25:37 am
No not looking for any reflex yet just noticed it deflexed but that is actually clearing up already starting to straighten out. Figure I'd put a layer down get the bamboo glue it up after it cures reverse string and add two more layers for a total of three.
Title: Re: Is it worth it
Post by: mullet on December 08, 2017, 12:28:45 pm
I've done the same thing you are doing except I glued my bamboo on and tillered the bow to about 80%, then glued on three thin lifts of sinew with it tied into a shallow reflex. As it dried and pulled the string loose I just tightened it to hold the reflex.
Title: Re: Is it worth it
Post by: Swamp Thang on December 08, 2017, 12:40:36 pm
I've done the same thing you are doing except I glued my bamboo on and tillered the bow to about 80%, then glued on three thin lifts of sinew with it tied into a shallow reflex. As it dried and pulled the string loose I just tightened it to hold the reflex.

Okay so did you tiller the back then ?
Title: Re: Is it worth it
Post by: mullet on December 08, 2017, 05:58:00 pm
Yes, that's why only 80% give or take. Tillered the back till I thought my luck was running out. If you put too much bamboo on you are stuck with the poundage you end up with. Also, if you put too much sinew on it can overpower and cause the bamboo to fail. Put a lift on, let it cure and see what you have before you put another one on. The longer the sinew cures the stronger the bow gets, also.