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Kronos "fusion roller" speargun design

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May 3, 2022
Figured it would be worth sharing some rendering pics of my recent R&D for my new sustainable bamboo product lineup. The Kronos bamboo speargun is a fusion roller design (fusion what??). Essentially, the bands would invert around the top of the gun, then transfer to dyneema tied "in-line" with the band on the belly of the speargun. I anticipate on having a belly kicker band tied on also. In essence, it will be an inverted roller speargun but without the pulleys. Which will increase power and simplicity of rigging.

The inversion of the rubber would eliminate all recoil. And the Kronos would shoot very snappy and flat since dyneema would be running around the pulleys at the front. I noticed in my research and testing that standard rollers have huge amounts of parasitic power loss from rotational inertia when the bands whip around the pulleys. Which is not ideal to say the least.

I added modular ballast plates to the front and the back of the speargun to adjust the center of gravity, and so the scuba bois can add some more lead to make the gun sink with or without the shaft. The mech is my "american style" roller mech that accepts both euro and american spec shafts. I tested it to 2000 lbs; it is stout.

I am currently running an 8mm two piece titanium slip tip shaft which has been nice. It weighs and performs like a 7mm shaft, so it shoots ridiculously fast on the rollers. I also added a "break line" in the front section of the two piece shaft, so if it does bend it will consistently only bend at the front section. Im fond of the idea of only needing to replace the front section of the shaft similar to how my polespears only need injectors swapped upon bending. My only concern is I have tested it only out to about 15 feet and I anticipate on the Kronos being a 20-25 foot capable speargun as a 115cm.

This project is an accumulation of a little over two years of R&D. Would love to hear your thoughts!


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Yep! Here's a pic of the latest and greatest. It has evolved quite a bit. You're welcome to contact me via email or on the black reef instagram for more info


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