Well I have tons of rubber from my spearfishing gun 14mm / 16mm / and 18mm diameter
Wondering if these can be used as engine.
Honestly I can see that they can have a limited stretch (but lot of power) compared to band or small diameter tubing. But using some hi tec cordage like Dyneema or Kevlar cord that I have I for instance use 10cm of rubber and then rope. A mixed. It is used also in several spearguns.
For instance a 14mm rubber streched at 300% can hold 20kg of force. Using less rubber or lower stretch factor can lead to a less powerful shot. On the opposite.
If they can send straight a 500gr shaft inside the water, probably only 5 to 10cm of this rubber with the remaing legth of cordage can do a lot for few grams of pebble or lead or whatever.
Comments are welcome? Too much crazy idea?
Im going to ask but and to test also in my wooden home made Y
Ok found some replies in the forum....