Working with rawhide

[steve b.]

Thank you for the generous offer and I'll take you up on that.  I want to make a smaller, lighter pull weight Molly out of another board I have.  One question I have though is why do I want to trim the dog chewie rawhide?  The rawhide is there to protect you in case the board explodes on you while tillering.  Why wouldn't I want a thick piece to protect me?  I can always sand it down thin when it comes time to finish it.   

I would say that its really not there to protect you from it breaking, its there to protect the bow from breaking.
By laminating such a thick, protective piece on the working part of the limb you are, in affect, laminating on something that will affect the tiller and effectiveness of the limb.  If you were adding something like wood or sinew that would enhance performance then that's fine as long as you realize its going to add draw weight to the bow.  You can therefore retiller at that point and decrease draw weight if you need to, with the end result that you have an efficient limb, because the laminated material is efficient for the function.
But I'm guessing rawhide is not one of those materials.  You are dumbing down your limb with a mass of inefficient material.  You are thickening and inhibiting the limb from moving as quick.  You'll add draw weight, but after you retiller you'll have less working wood and more nonworking rawhide as your working limb.

So you want the rawhide to not affect the function of the limb, but yet still protect the wood fibers from lifting.  So you want it as thin as possible.

At the price that CMB is offering I would buy as much of it as possible because that's a super deal and I know its not about the money for him but about his contribution to cause.

[Bryce]

Well put Steve. If I didn't have so much rawhide I would be jumping in Carson's deal as well.

[Loneviking]

As somebody just starting to make bows, this is what confuses me:

Steve B.:

By laminating such a thick, protective piece on the working part of the limb you are, in affect, laminating on something that will affect the tiller and effectiveness of the limb.

Bluegill 68:

Although the rawhide does shrink a bit while curing it does not add appreciable poundage to the draw weight or change tiller.  Bottom line it is not a cure for shortcomings in tiller or asking too much out of a piece of wood.

(From the thread Rawhide Along)

So who's right?  I dunno, but I can tell you that the backed limb seems to be moving just as good as it did before. 

Steve B.:
 

You'll add draw weight, but after you retiller you'll have less working wood and more nonworking rawhide as your working limb.

So you want the rawhide to not affect the function of the limb, but yet still protect the wood fibers from lifting.  So you want it as thin as possible.

But Steve, why does less wood and more hide make a difference?  If it's glued down well, and the bow tillers out to the desired poundage,  the arrow isn't going to care if it's thrown out there by wood or rawhide.   A horn backed bow (as an example) has the horn helping to throw the arrow, so I can't see that there's going to be any detriment.   

I'm not saying you're wrong Steve, I'm just trying to grasp the underlying concepts of working with this stuff and figure out why there are such widely varying opinions on what the effects are on using it.   

[Bryce]

The thick rawhide adds weight to the limbs. Slowing them down. And can result in poor cast. Rawhide does not add draw weight like sinew does on a horn bow.
Thinner rawhide weighs less and you get the same amount of protection against splinters.

[Loneviking]

The thick rawhide adds weight to the limbs. Slowing them down. And can result in poor cast. Rawhide does not add draw weight like sinew does on a horn bow.
Thinner rawhide weighs less and you get the same amount of protection against splinters.

OK, makes sense that rawhide would add weight although being a board bow (and thick) it's probably not much in relation to the total weight of the limb.  I was going to sand it down flat after tillering to glue Stingray skins on it.  Any benefit to sanding it down before tillering?  That and 'how thin' is what's puzzling me!

Bill

[mwosborn]

Really only 2 reasons to use rawhide as a backing as far as I can see...

1.  You simply like the looks of it or you want a canvas to "decorate" your limbs.

2.  You want to help protect the back from splinters (perhaps a ring was violated or back has some minor run off or something).

Therefore, a nice thin strip of rawhide is all you need.  Deer works well (fawns or young deer best IMO).  As Bryce said, this will protect the back from splinters and at the same time add very little physical weight to the bow limb.  Too much weight on the limb will slow it down.  A thick piece of rawhide from a dogbone will need a lot of sanding!

Good luck

[Bryce]

Steve b. Turned my onto goat rawhide, now that's some good stuff. Almost transparent. Kangaroo rawhide is awesome too.

[randman]

Del, I took your advice (and a couple of others above) and staked the rawhide to a wood slab.

Actually, I'm Randman...only put Del's name on there to counter my reference to skinning a cat 
And yes 90% of the dog chews out there are too thick (adds too much unnecessary mass) in my opinion...too much work to thin after processing flat.....I only grab them when I see one that has very thin edges.....and they are not less expensive...at $14 for 2 of them big enough to use (my last purchase) and MAYBE you'll get 2 usable strips out of them, Carson's offer is very affordable and generous.....I'll be contacting you soon there Carson....

[steve b.]

Loneviking,

The arrow doesn't care what throws it, you are right, but it will be thrown alot faster by a bow made of material that when bent, straightens back up very quickly.
It will straighten back up quicklly if it has those strong but elastic properties but also if it as light as possible.  Some woods have those inherent properties more so than others so when we want the most efficient bows we chose woods that will bend, not break, not set, and straighten up as fast as possible with the least amount of material for the draw weight that we want. 

So if you take a perfectly good shooting bow and laminate on a strip of rubber on the back, in order to protect yourself when it explodes, or to keep it from exploding, you are adding material that is very elastic but also very heavy.  So you'll slow your limbs down from straightening back up.  Rubber doesn't want to straighten back up very quickly.  If you glued on a strip of carbon fiber to hold your bow together then you would notice it would straighten back up quickly, but it would also be harder to pull back where as the same amount of rubber would affect the draw weight less.  So the carbon fiber is helping your arrow and the rubber is hurting it.

[steve b.]

Here's a bow that I backed the other day.  Still needs cleaned up.  You can see how thin the rawhide is in this pic. 

[steve b.]

I love rawhide.  It fits perfect with my philosophy of what primitive should be, and my other philosophy that comes from how cheap I am.  I could back every bow that I'll ever make with only rawhide and be happy.  I might change my handle from Steve B. to Rawhide.   

[steve b.]

.

[JW_Halverson]

For some of the people less experienced, they may be confusing weight and weight.  They are spelled the same, pronounced the same, but are radically different.

Rawhide adds weight (mass) to a limb, but sinew will add weight (draw weight) to a limb. 

Meanwhile, we will wait (oh how I live a pun) to see how your bow turns out.