Build a Recurve Bow
By David Radtke
|I got my first bow for my fourth birthday. It was plastic and thank heavens the arrows had rubber tips because everything within a 30-ft. radius was fair game. These days I exercise better judgement and only shoot at designated archery targets, but my fascination with this ancient technology is as strong as ever.
Several years ago I built my own wood and fiberglass recurve bow from a kit. The “recurve” refers to the way the bow curves away from the shooter at the tips. This gives the bow more snap when the arrow is released. Building the bow was almost as exciting as shooting it. Since then I’ve built several bows, each with a feel and character of its own. They’re beautiful to look at and fun to use. There aren’t too many woodworking projects you can play with outdoors!
A bow may look complex, but the kit I used makes it pretty straight forward. In this story, I’ll show you how to make a bow from one of these kits. No specialized tools are required, but you will need a bandsaw and an oscillating spindle sander to shape the bow. A drum sander in a drill press can substitute for the spindle sander.
The bow is laminated with thin strips of wood and fiberglass. They’re bent and glued together with epoxy using a plywood form. You don’t need a zillion clamps to squeeze the forms together, however. The kit’s manufacturer has a better idea: to apply clamping pressure, you inflate a fire hose with a bicycle pump. Then, you place the assembly in a shop-made plywood box equipped with incandescent light bulbs. The bulbs provide the heat necessary to cure the epoxy. The result is a one-piece recurve bow with incredible strength and flexibility.
Build the forms
1. Use the full-size paper patterns from the kit
2. Rough cut the other plywood layers about
3. Glue the layers together using 1-3/4-in.
4. Once the glue is dry, use a router with a
5. Drill a 1/4-in. hole in the center of the lower
6. Glue the reverse taper strips (Fig. B) onto
7. Install the locking hardware on the form
8. Build the laminating oven using 1/2-in.
9. Wire in the porcelain light bulb sockets and
Prep the laminations
10. Cut the riser block to length. Find the center
11.Trim the wood laminations to 32-in. Then,
12. Cut both bottom pieces of Bo-Tuff fiberglass
13. The Bo-Tuff has a smooth and a rough side.
14. It’s imperative to have everything (including
15. Roll out an ample length of plastic wrap over
16. Lay all the lamination pieces onto a papered
17. Lay the lower Bo-Tuff and tapered laminations
18. Coat the riser with epoxy. Set the riser on top
19. Wrap filament tape around the form and
20. Lay the deflated hose over the pressure strip
21. When the curing is done and the form has
Shape the bow
22. Sand the bows edges to remove excess epoxy
23. Draw a centerline along the length of the
24. Mark the limb tip shape (Photo 11).
25. Rough-cut the shape of the bow limbs on the
26. Start the string groove cut with a triangular
27. Reinforce the tips with a tip overlay
28. Remove the tape at the tip and lightly
29. Remove the tape on the bottom center portion
30. Check the bow for uniform limb stiffness
31. To limber up a stiff limb, remove the string
32. The next step in tuning your bow is called “tillering”.
33. Use paper patterns to trace the bow grip and
34. Rough out the grip shape on a bandsaw with a
35. Finish sand all the bow surfaces. Start with
(Note: Product availability and costs are subject to change since original publication date.)
Bingham Projects, binghamprojects.com,
Home Center, 4 sheets 1/2″ CDX plywood; 1 – 2x2x8′ pine. 5 – 4-in. x 1-1/2″ octagon steel junction boxes; 8 – 1/2″ EMT set screw connectors and lock-nuts; 10′ of 1/2″ EMT conduit; 1 – 1/2″ metallic chord connector with strain relief grip; 10′ of black and 10′ of white, 16 ga. stranded high
Fig. A: Bow Laminations
Fig. B: Form
Fig. C: Heat Box
Fig. D: Wiring Diagram
This story originally appeared in American Woodworker October 2007, issue #131.
|Click any image to view a larger version.
1. The first step in bow building is to make the form for gluing the bow laminations. The form is composed of four layers of 1/2-in. plywood glued together. One layer is a template cut to the exact shape. The other pieces are cut oversize and trimmed to match later. A notched trowel makes a great glue spreader.
2. Flush trim all the form layers with the template layer. The top half of the form is built in the same manner.
3. Glue the reverse taper strips to the lower form with contact cement. Make sure the thin end goes against the index pin. Add plastic laminate strips on top of the reverse taper strips to create a smooth surface on the form. The steel index pin is used to anchor the riser block in the form.
4. The bow’s handle is shaped from a large block of solid wood called a “riser block.” Sand the riser with an oscillating spindle sander or a drum sander. A backer board allows you to feather the risepaper-thin thickness.
5. The bow is composed of three types of laminations: strips of solid wood of uniform thickness, strips of solid wood that taper in thickness from end to end, and strips of Bo-Tuff fiberglass. Coat all of these pieces with slow-setting epoxy.
6. Butt the bottom pair of laminations against the index pin on the form. Set the riser block over these laminations so the hole drilled in the back fits over the index pin. The top laminations will lay over the riser. Plastic wrap protects the form from epoxy squeeze out. Wrap filament tape around the laminations to keep them from sliding around on the bottom form.
7. Pump air into the pressure hose to apply clamping pressure to the laminations. The pressure hose is set on top of the laminated bow in the form. The two halves of the form are held in place with metal straps and bolts that come with the kit.
8. Set the form in a shop-made plywood oven for a four-hour bake. The oven is heated by incandescent lights. Heat is needed to cure the slow-set epoxy. Remove the form after it’s cooled overnight.
9. Sand off the excess epoxy. Wear leather gloves because the epoxy can have sharp edges. Keep the protective masking tape on the surface of the limbs as long as possible to prevent scratches.
10. Use a bridge shaped template to mark the length of each limb (top of the bridge) and to position the grooves for the string (underside of the bridge).
11. Align a paper pattern with the limb’s centerline and the string groove mark. Cut the shape on a bandsaw and finish shaping the edges with a drum sander.
12. File the string grooves with a rat-tail file. The angle should be approximately 70-degrees to the tabletop. Check the backside of the bow often to make sure each side is symmetrical.
13. Due to variations in shaping and sanding, one limb may be stiffer than another. To test, string the bow and measure from the end of each riser overlay to the string. A stiffer limb will measure shorter.
14. Check for twist in the limbs. Make a tiller stick to pull the string and flex the limbs. If one limb is twisted, mark the side that is high. Sand the high edge to remove enough material to correct the twist.
15. Draw the arrow notch and the hand-grip profiles using the two patterns provided in the kit. Cut the profile for the top first as shown and then lay the bow on its side to further cut the hand-grip area.
16. Use a combination of rasps and small drum sanders to custom-fit the bow to your hand. Once you get it right, start sanding the wood areas with 80-grit sandpaper. Don’t sand the fiberglass surfaces with anything less than 120-grit sandpaper or you’ll leave deep scratches that are hard to remove.
17. Finish your bow by suspending it from a wire attached to the string grooves. Spray several coats of gloss varnish to protect the bow and bring out the wood’s beauty.