ADDENDUM: I made a bowstring release from an eye bolt which was cut and sanded to be smooth against my index finger. Works well.
A friend sent me a video on trick archery and that got me interested…I found many You Tube presentations about bows and settled on the best for DIY bows: Backyard Bowyer (Nick Tomihama) His videos are detailed and his books have even more information.
One needs a work surface (I use a folding workbench), a heat gun (I use a Wagner HT 1000), aluminum foil to place on the work surface under the pvc tube (this increases the rate of heating the pvc), one or two 2×4 pieces of lumber (I use one and the garage concrete floor), and leather gloves (pvc gets hot). If you don’t like the result just reheat the tube and it will return to its original shape. Three fourths inch diameter schedule 40 pvc pipe is fairly easy to work with the heat gun. One inch provides a stronger bow and takes quite a while to turn into a “wet noodle” for forming. PVC gives off gasses, I understand, so work in a ventilated, open area.
The limbs of the bow need to be flattened as much as possible for “springiness” when drawn and shot. Weight is adjusted by the diameter of the pvc, length of the bow, reflex and deflex of the limbs and how the tips are formed. A lot of experimentation is thus possible. My favorite to date of the ones I have built is the 3/4 inch blue one. (The black bow is excellent also).
I use one half inch cpvc to for an arrow rest and mount it to the bow with the abrasive adhesive tape used on wooden stairs to prevent slipping. This provides a very nice handhold. A piece of the fabric side of velcro is attached above the arrow rest to the bow finish is not worn off.
What I call paracord comes in several strengths, not just 550. Her bowstring is rated at ~50 pounds and is thin enough not to seize the arrow nock and slow the arrow. I should probably use a real bowstring. One end of the string is just an overhand loop knot, the opposite uses an adjustable bowyer’s or archer’s knot and I use a simple overhand knot for the knock point after experimentation with the string height above the bow.
This bow I made for my wife uses 3/4 inch schedule 40 pvc. It is the nicest DIY bow yet with a smooth pull and a really pretty paint job (black on the back and red on the belly of the bow.) I used reflex only (limbs bent away from the shooter when the bow is unstrung) and just enough reflex to give it some draw weight without over stressing the pipe and risking failure. The siyahs (flat part on the ends) are a couple inches too short so the bow creaks as it is drawn from the string sliding along the bow surface. A nice touch I think.
I use aluminum arrows and they fly true. Workspace and result:
Here are a few more. I purchased the black horsebow from ETSY. The pvc arrow quiver is pushed into the ground next to me when I shoot. There is a bunched up rag in the bottom to protect the arrows.
This is me before I learned how to shoot