Heads-up: I filmed this series back in 2014 (about 12 years ago), and it’s not how I build bows today. It’s still a solid walkthrough for the general idea, and the dimensions are spot on for a proper bow.
What I do in this part
After the riser from part 3 has cured for 24 hours, I unclamp it, shape the ends of the handle block, and back the bow with fiberglass and flexible epoxy.
Why back a board bow
A store-bought board almost always has some grain run-off. Without backing, those fibers can lift and splinter off like really big toothpicks. Backing holds the back together.
Tools & materials
- Fiberglass cloth
- G/flex epoxy. It must be a flexible epoxy.
- Bandsaw, rasp, or Dremel for shaping the handle block
- Wax paper
Other backings that work: sinew, snakeskin, fish skin, paper bag, sheetrock tape, or fabric. The riser can also be a poplar and oak sandwich.
Shaping the handle block
- Slope the ends of the handle block. Eyeball it, and don’t cut into the belly.
- Optional: carry the slope about 1/16″ into the belly, about 1″ or more past the handle, to keep the handle from popping off. Then taper the belly out to the tip so you don’t create a hinge.
Applying fiberglass with G/flex
- Mix G/flex 1:1 resin to hardener. The hardener is thicker, so watch your amounts. You get about 30 minutes of working time.
- Brush a thin base coat on the back.
- Lay the glass down. Make sure there are no stray threads.
- Add a second coat until there are no white spots and no wood showing through. Double it up for heavy bows.
- Let it cure 24 hours, then add a third coat.
Alternative: cotton backing
Use rugged cotton, like GI desert camo (not bedsheet cotton). Soak it in Gorilla, Titebond II, or Titebond III cut with a little water. Put a base coat of glue on the back, lay the cloth, cover it with wax paper, and let it sit 24 hours.
Up next: Part 5, prepping the bow for tillering.