Gluing Rawhide and Veneer to Self Bows, Part II, Continued

By Dean Torges

 

The Process

Mist the rawhide on both sides with a squirt spray bottle. Don't soak it. If you don't have a spray bottle, dip the rawhide in the reservoir of warm water and squeeze off excess moisture between your thumb and forefinger. In either event, set the rawhide aside to relax while you spread glue over one limb.

When the rawhide has become supple, spread a layer of glue over the flesh side. Notice the affinity of glue and hide. Resin glues (Titebond white and yellow and Type 11) act like oil on water at this stage. Give things several minutes to chill off while you recheck the iron temperature and hone your pocket knife/trim tool.

Starting at the handle, position the rawhide the length of the limb and iron down the first 5 to 6 inches. You've already glued glue to rawhide and glue to wood; now you are gluing glue to glue. Don't let the rawhide dry out and don't let the iron get too hot.

As soon as you have re-melted this section of glue, exchange the iron for the hammer. It functions to squeegee any air and all excess glue from between the rawhide and the bow back while making good advantage of the natural suck of hide glue. The glue hereby becomes its own internal clamp.

Thoughtful tool manipulation will assure you of a good bond. Wiggle the tool handle back and fort has you simultaneously sweep the tool in a gentle arc from the center toward each edge in turn, lapping each sweep like fish scales. Work from the handle to the tip. Remember, the object is to move air bubbles and excess glue ahead and off to each side, not back and forth and up and down.

Keep the rawhide moistened and the hammer warm. Don't worry if glue slops on top of the rawhide. It serves to lubricate the metal blade and has no adverse effect on the finish. Indeed, glue purposefully dabbed atop stubborn or rough areas 1 Lubricates the hammer and helps coax them into place. After one section is down, move ahead with the iron to the next section. (Don't forget to place the hammer back in the hot water bath.) There's no need to hurry. Only with hide glue can work speed be determined by your own individual comfort level rather than by glue constraints.

You can't mess up if you pay attention. If you overwork an area and suspect you've starved the bond of glue, lift up the rawhide and take a peek. Wipe down a little more glue, reposition the rawhide and make the necessary adjustments in iron heat or tool pressure and manipulation (hammering).Familiarity with the process produces a straight-ahead job in short order. After a bow or two you won't feel the need to backtrack and the work will move quickly.

You should end up with a uniform amount of glue squeeze under the rawhide overhang down both sides of the limb as clues to a good job. If you don't, moisten the area, reapply the iron and squeegee the doubtful section over again.

When you've finished one limb, run a sharp blade down each side to trim off excess glue and rawhide while they are still soft, being careful that the slanted blade pressures the rawhide down against the bond (as opposed to pulling it away). Don't worry about the rawhide shrinking back from the edge with further drying. It won't because it never bloated in a soak. Besides, it is now glued down too tightly.

One of the advantages of this method over any other is that the process allows you to constantly monitor the results. If you see trouble, you can rework areas until you are pleased with the bond. No guesswork.

No great long setup time, either. YOU can begin final trim and cleanup within several hours. When the excess glue becomes gelatinous, it peels off readily. By then the rawhide will be dry enough to file or sand. Either with a second cut file or a large mill bastard, maintain one angle along the edge of the rawhide and, without removing wood, feather it into the bow's radiused edges for a neat and uniform trim.With warm dry weather or temperate use of your heat box, you can tiller and string, up within 36 hours.

Additional Tips

After the rawhide is quite dry, usually within 12 hours, run your fingers over it lightly with your ears close by. If you find an area that "whispers" as your fingers travel back and forth, the bond there is unsatisfactory. Heat up the iron, moisten the area, revitalize the glue with the iron and work the bubble down with the hammer or the roller. It'll fix.

You may wish to add two auxiliary tools. One can be had by modifying a wallpaper seam roller.Simply replace its wooden wheel for one of solid brass or copper, and use this tool as you do the veneer hammer. You may come to prefer it over the veneer hammer for working edges or for lumpy areas such as knot clusters. Keep it hot in the water bath, too.

The other is the serrated plane blade used in toothing planes. You'll need one when we get around to building a toothing plane, which I find indispensable for thicknessing components and preparing glue surfaces for composite bows. For now, the blade itself handheld and dragged across the bow's back prior to spreading glue creates an ideal glue surface. The tiny troughs which result greatly reduce the risk of starving the bond between rawhide and wood, and a starved glue joint is probably the only worry that need concern you through the hammering process.

Rawhide sucks moisture like a sponge. To maintain the bond, apply a good finish (see TBM SelfBow column, Jun/Jul 97). Even a Titebond II bond requires protection. It is water resistant, not waterproof. If you need a demonstration of the difference, leave an application brush into which it has dried thoroughly in an overnight water bath.

This process yields smooth and uniform results. There is no need to have a hide-bound bow marred by the tracks of string wraps and tie-downs or peeling loose in places like a reptile in slough. You may have to live with many kinds of mistakes, but you don't have to shoot with them.

In the next and final installment of this process, we will look at using this technique for applying inexpensive furniture grade hickory veneers to bow limbs for advantages beyond those provided by rawhide.

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Source of Supply: Cabinet makers' veneer hammers and toothing plane blades can be purchased mail order from The Garret Wade Tool Company. Phone (800) 221-2942.

Copyright 1998, Dean Torges