A bow update

Work on the bow has now ceased. The result is a bouncing baby bow, much loved and adored.

This means that those with time to blow can now get a recipe for the cheap recurve they have always wanted:

  1. Make a mould. Use planks of wood, cut and joined to form the shape of the unstrung bow, with an overall length of 1.2-1.8m (1.5 is my preferred size). For best effect, a mould in the shape of an unstrung Mongolian bow (a complex house-roof-shape-thing) is best. Otherwise, a simple recurve (a flat top with downward-pointing tips) is fine. Wrap the mould in cling-film.
  2. Use plain nylon fabric, cut to the correct length and breadth, to make the front of the bow. Glue in layers (about 5) with resin, taking care to spread it evenly and not to wrinkle the fabric or leave too many bubbles. Try to use as little as possible, as this will produce a stronger structure.
  3. Use fibreglass tape (the sticky, unwoven kind) to make the centre of the bow. As before, take care to spread the resin evenly and thinly. Layer whole lengths for a bit (up to 10 layers) before stepping the layers by cutting and laying progressivly shorter strips of tape. I used a step of about 5cm, working down from 1.5m to about 30cm at the centre of the bow. At the end of this process, you can lay 5-10 more short layers at the centre to strengthen the handle.
  4. Use woven fibreglass tape, cut to the correct thickness, to make the inner part of the bow. To get it to lay properly, it needs to be carefully brushed from the centre outwards. I used 2 layers running from the end of the handle area to about 3/4 of the way to the tip, followed by 4 layers running the length of the bow and more layers at where the bends were. This had more to do with the fact that I could only buy the stuff in 2m lengths than anything else.
  5. Test the bow and add extra pieces of nylon or woven fibreglass tape to even out the bend of the bow (it must bend symmetrically) or add to the draw weight. Cut sections out of both sides of the tips for the bow-string loops to attach to. Cut and reinforce anything else that needs cutting/reinforcing. A powered jigsaw works well for this.
  6. Use an angle grinder and belt sander to remove jagged edges and lumps of extraneous crap. Smooth the handle down a bit.
  7. Wrap the bow in duct tape (or nylon etc.) to protect it and keep the layers together.
  8. Make a string for the bow.
  9. String the bow. Fire the bow. Repeat.

Remember that resin has a finite lifespan once activated. Rather make small batches and do a few layers at a time than waste the stuff. Also, remember that the bow must be unstrung when not in use. The shape will change as everything gets stressed. Stacking before first firing is advised. Chop-strand fibreglass mat can be used in place of the unwoven fibre tape, if you’re a masochist.

This project is obviously recommended for someone who has used bows before and has at least a cursory knowledge of bow making. It will take about a month and cost about R250 if no wastage occurs. Resin will be the most expensive component.

Good luck.

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