what is the trick to rawhide backing

[jayman448]

over the past few weeks i had been tinkering away at a maple board bow which I decided to back with rawhide due to the fact it was a sub par board. It did not have perfect grain however i decided it wouldnt be a problem. so I got the thing floor tillered, backed it, and got it tillered out to my 27 inch draw. at that time it was 67". i took it down to 65" as i missed the mark with my draw weight. all was seemingly ok, i had shot it several times, and was just waiting to get around to do a little heat treat before I finished it. Anyways. I went to take a couple shots just for poops and hahas, and it just didnt feel right. anyways i ignored it. warmed it up, drew it back. was ok, knocked an arrow, and boom.  It is plain to see that my glue did absolutely nothing in the way of adhering to the rawhide. just peeled off and exploded leaving me with a hole in the wall from where the top limb embedded itself in the gyprock, and a minor cut on my eyelid .... what did I do wrong?

[PatM]

Glue used and preparation of the two surfaces.  You can't heat treat AFTER putting rawhide on so that would have doomed it anyway.
 

[Pappy]

What PatM said on both accounts, also remember that raw hide will help hold down a splinter but it's not the save all, if you have a real problem with the stave , rawhide won't save it.
 Pappy

[stickbowbeard]

How did you back it?  What was your process?  I have only done it twice, so I reckon there are people in here that can provide more wisdom than I can, but I'll tell you how I did it.  My first one was a rawhide-backed hickory board-bow.  For this, I scrubbed the back of the bow with warm water and dish soap to eliminate the oils in the wood, when it had dried somewhat, I sized the back of the bow with TB3, most of which was absorbed into the wood, clearly demonstrating the need to size the wood.  Then I applied another layer of TB3, and layed the wet rawhide down on it.  I worked from the handle to the tip, gently smoothing the rawhide to the back of the bow with my thumbs, pushing from the center out, to make sure I pushed any air pockets and/or excess glue out, and then I wrapped it tightly with ace bandages.  The major learning experience for me on this first one was to not wrap it too tightly.  The ace bandages are definitely imprinted on the rawhide.  However, it ended up yielding a 50# bow that I shot thousands of times, and hunted with in 2016.  Then I reduced the limb width a little and decreased the draw weight to 30# or so and re-purposed it for my wife to shoot.

The next bow I used rawhide on was an Osage bend-through-the-handle bow.  I basically followed the same process, with emphasis on making sure to scrub the back of the wood to remove the oils.  This time, I learned from my previous mistakes and when I wrapped it, I wrapped it very lightly.  It came out beautiful, and I could tell that the rawhide had adhered nicely to the entire length of the bow with no air pockets or anything. It turned out to be a 34# bow, but it is only 45" long and draws 25" with minimal set, so it's pretty extreme, and holding up nicely so far.  This one maybe hasn't stood the test of time yet, but it's had hundreds of shots through it now.

Again, I'm still an amateur with rawhide, so this is just my experience with it.  I'd love to hear tips from others that are more experienced as well.  If you share how you actually did it, I'm sure someone with more wisdom than I can help you figure out where your mistake was.

[RatherBinTheWoods]

What they said. :0) Rawhide will keep splinters down no problem so it will save bow in that sense but if the woods gonna go it'll still go with rawhide on or not. I use deer rawhide all the the time for decorative effect as I get stuff that almost looks like bark. Use Titebond III I haven't found anything better and it's waterproof. De-grease the back and put a sizing layer of glue on the wood (and the hide of you like, I do) first - let it dry then glue on both wood and hide. I keep it in position with cohesive bandage - the stuff that sticks to itself that they use on horses legs - while it drys for an hour or two. This also keeps the surfaces tightly together as it dries. Make sure the hide isn't slipping sideways as you wrap it. Unwrap after an hour or so and force out any air bubbles if necessary (it'll be quite well fixed by this time usually) then wrap again over night. Should come out perfect.

[PatM]

It's actually hard to beat hide glue or gelatin for applying rawhide. Easier in many ways and probably gives a better bond..

[bluegill68]

Here is an old post on how I do it.

http://www.primitivearcher.com/smf/index.php/topic,32398.msg428391.html#msg428391

[Pat B]

I use hide glue as PatM said.  Also I not only clean the back of the bow with Dawn and warm water I rinse with boiling water. I hydrate and clean the rawhide(sinew also) with warm soapy water and rinse well. The oils in the rawhide can be a problem. I add the glue to the rawhide and the bows back while they are still wet because I think it helps the materials absorb the glue. If the rawhide is thin enough I don't wrap but If I do wrap I use strips of old bed sheets. After about an hour I remove the wrap to be sure there are no air pockets or excess glue pockets. If either show up I will cut a small slit lengthwise with a sharp razor and eliminate the air or glue them press the area with my thumb to close and seal the slip. Then I let it all dry until I'm sure the wood has had time to dry.

[NorthHeart]

Based on your description im not sure that the rawhide job was the culprit.  But i have backed almost everybow ive made for the cheap insurance it provides, or for artwork.  Ive used exclusively Titebond3.  First sand the back and acetone it to remove all oils.  If im heat bending the wood with oil, i do that first then make sure and remove that contaminated wood down to fresh wood and then acetone it.  Then mix a small cup of thinned down water and glue(approx two thirds glue).  You coat the back of the bow with this and let it dry.  You do this 2-3 times.  Your rawhide has been soaking for an hour or so and its now fully hydrated.  You scrape the backside with a knife against a board to remove any gunk/hair/membrane.  Put glue on the rawhide, smear it all over.  Lay it on the bow and starting from the grip work your finger all the way down removing any air pockets.  Wrap it in ace bandage letting it cure for an hour or so(meanwhile you do the other side).  After an hour remove the the bandage carefully, as the glue has now thickened but is still tacky enough you can make adjustments if necessary.  After this you are supposed to put the ace bandage back on to let it set over night but i have found this step unnecessary. By morning you can ususlly rasp the sides.  In 2 days time its hard like a rock.  I try and wait 10 days or so for the wood to cure back out.

Out of eveything on bow building that i have messed up along the way, this method has worked 100% of the time.  I learned it from Mike Yancys video.  I would still like to learn the method of hide glue better, and become as comfortable with its results.  But TB3 is waterproof and has been a fool proof method so far.

[PEARL DRUMS]

The poor grain you decided was no problem, was. 

[jayman448]

ok time for clarification. I maintain the grain was not the issue. too hard to explain how it was, but basically the 'problem" was that it ever so slightly would not allow for me to follow a single grain on the back so i backed it. the glue held to the wood just fine but peeled away cleanly from the hide. my process was sizing the bow (no degrease), warm soak and general rinse (again no degrease) on the hide. glue on both the bow and backing, then lay out and wrap the ever lovin jesus out of the thing with tenser bandages as tight as i could. then an ungodly ammount of spring clamps up and down the entirety. stupid rookie mistakes but i feel the oils must have done a number. probably the glue too. oh well. learning process. least i was actually happy with my tiller so there is something for a noob. 

[PatM]

Your glue was probably gelled and never blended together.   The clamping and tight wrapping was totally unnecessary.  You can apply rawhide with hide glue without even wrapping if you use warmth to keep the glue active.
 Even if you do wrap it high tension is not needed.

[PEARL DRUMS]

I understand the glue adhesion wasn't good enough, but that isn't why your bow broke. Something in the tiller or the grain was amuck. The bow broke THEN the rawhide let go because it cant hold a bow together. I'm not trying to be an ass, I'm trying to get you thinking deeper than the surface.

[PatM]

I'm just wondering about how the rawhide peeled away though.  It sounds like it was just floating there like a cable.

[Springbuck]

Combination of factors.  First, it may have been the grain.  Maybe not by itself, but contributory. 

  Second, it was a "decent" wood (maple), but not a primium wood, and a "decent" board, but not a perfect board.  You heat treated the bow, moving the neutral plane toward the imperfect back as the belly hardened.

Next, you piked it to make weight, after flexing a lot and not making weight at 67".  No crime, but it was worked in at one length and weight, then changed, which changes tiller just a bit.  Backing was on at this point.
 
 Your glue process sounds like it should have worked, even though some steps weren't necessary, but the heat treatment to an already backed bow is what I think did you in.   While heating you may have had tiny amounts of hot air or steam lift the backing, some shrinking of the rawhide or the wood in spots (lifting the rawhide off of a dip on the back by shrinking it, perhaps?)  Or something similar.

 Anyway, you likely softened the glue and something bubbled, shifted, or slipped.  Then, when the back went under the rawhide, there was nothing to stop it.  AND rawhide will stretch just a little under tension, even dry.

BTW, I sure like what Torges did with rawhide.  Sizing both wood and rawhide with glue, then gluing glue to glue....