Understanding Backings

[Wolftrail]

Many self-bows are built using sinew as a backing. Is the sinew merely for added insurance or increased weight.
Having said that from personl experience I noticed that silk is not a good backing for much, one bow snapped on the tiller tree and the silk backing broke. I would think nylon or polyester would do a better job.
And why be a die hard fan of natural backings when the synthetics do a better job with less work, instead of silk and paper backing.
Other than the fact that one wants to keep in traditional values.

[takefive]

I guess it all depends on what type of bow you want to make, whether you use a board or a stave, and what looks pleasing to you. I mainly use hickory backings because boards are readily available to me (unlike staves unfortunately) but the boards I use for the belly have less than perfect grain.  I can glue reflex into the bow as well,  and if I make a tri-lam, it's not hard to make it reflex/deflex or even recurve it.  With a table saw and a belt sander it takes very little time to rip the lams and get them flat.  Using Unibond for the glue up, I can start tillering the next day.  Also like the way hickory looks with a dark or golden brown aniline dye.  Cherry bark makes for a very pretty backing as well.

[Ice Mike]

Sinew can be used for both, depending on what you are trying to do. To add insurance, one or two layers of sinew works very well. To add weight or reflex, 3-5 layers of sinew with hide glue can't be beat if you let it take enough time to properly cure. I would put sinew against any synthetic you can come up with besides fiberglass and I'll put my money on the sinew every time. It's a huge pain to work with and apply, but it does work. I have a sinew backed tri-lam that still shoots great right now that should have broke 200 shots ago.

[macbow]

Sinew is magical if used properly it enhances the wood properties.
From my experience silk, drywall tape, linen, cloth etc. Is only good to help keep splinters from lifting and reducing the blow up effects.

Hickory or bamboo are real backings and in combination with woods with good compression qualities.

[Iron Eagle]

Sinew is much more than a way to hold splinters down and add insurance. It has the ability to greatly reduce string follow since it shrinks when it dries thus pulling the bow into a reflex. If used properly and in moderation it can a very high performance bow. Here's why, we know sinew is heavy so using it in moderation is key to such a bow. But design is also key. You can make a shorter bow with less width and re curve or retro flex the tips to take advantage of the sinew. Like horse bows,Turkish flight bows, certain native american bows, etc. You can also take a less than stellar wood and make it a top notch performer. Eastern red cedar takes sinew well for example. So if you plan from the start to sinew try and make your design take full advantage of the sinew. Taking a 66" hickory with 2" wide limbs then applying sinew will make a very durable long lasting slug. But a 62" with 1.75" limbs with some reflex or recurved tips you'll have a nice performing durable bow. I use hickory as the example because I use it so much and have sinew backed some with poor results and with great results. That is my  hands on experience with sinew and knowledge I have read. I hope it helps in understanding it's true potential.

[Wolftrail]

I have read a lot about backings but sometimes its good to get as many opinions, thoughts and ideas from many other bowyers.  Thanks for the tips guys.

[KenH]

There are two reasons for backings, as mentioned above -- 1. helping keep the back from splintering etc.; and 2. adding strength.  

Sinew is the preeminent natural backing for adding strength.  Backing with a thin lamination of other wood/bamboo is the second best natural material. There's really nothing else until you get to wood-fiberglass composites.

Silk, snake/fish skin, cloth etc. are "safety" backings.

[Robyn Hode]

I agree with Macbow silk, drywall tape, linen, cloth, etc. is only good to help keep splinters from lifting. I have backed board bows with silk and 100% linen and they will break if the bow breaks. I had a linen backed red oak bow break on the tiller tree. It snapped clean through the wood and linen backing. I'm glad I was not up close to it when it broke.

I also have a hickory backed hickory board bow. It has some set but is strong as H E double hockey stick. I like to back bows with hickory the best. I like the color of the wood and it will stain good.

[Pat B]

Silk, linen, hemp fibers, brown grocery bag paper and rawhide all make good backings for wood bows to help prevent splinters from lifting but they will not protect a poorly designed and constructed bow.
 Hickory, elm, ash and other woods make good backings if you want to add performance to a bow. Bamboo is another performance enhancing backing material.
 When I use sinew for a backing I specifically design the bow to be a sinew backed bow from the get go. Sinew will work for protection but other less tedious backing materials are more appropriate(IMO) and take less work to use as a backing material.