Finally finished my hybrid

    Well, it's finally done. This is intended to be a mid water freediving gun, that will let me hunt over Gulf wrecks where I can't reach the bottom structure, and want to take longer shots than my little Bay gun is capable of. I wanted something that would be a stable and solid platform, with enough mass to handle (3) 5/8" bands.


    It's not obvious from the pics, but the wood section is about half the total length (31") and the carbon fiber plus muzzle is the other half.


    62" long
    5/16" shaft
    50" band stretch
    Kitto M7 mechanism
    Spring resetting line release
    Loaded weights 9.5 lbs
    Shapelock grips on a Delrin handle frame
    1/8" thick carbon tube formed around a Syntactic foam core
    Laminated teak stock by "Wood Guy"




    Edited 2 times, last by Guest ().

    Here are a few construction shots:


    I molded the carbon fiber tube by wrapping uni-directional cloth around a syntactic foam dowel. The uni-directional cloth gives it great bending strength, but isn't pretty. So I covered it with a single sleeve of bi-directional cloth to pretty it up, and add a bit of compressive strength. The finished outside diameter was about 1.4", but the overall height with the shaft is nearly the same as a much smaller Rabitech barrel with its raised track.



    Here's what it looks like, with the delrin "dummy" piece to form the track, and the heat shrink around the outside that is used to squeeze out the excess epoxy.


    Another thing that I wanted to experiment with was using my mill to bore long horizontal holes. This worked out GREAT! I was able to drill a slightly undersized hole with a 1-3/8" Forstner bit, and then finish it perfectly to size by using a smaller Forstner with sandpaper wrapped around it. The tube is inserted 10" into the wood, and pinned with three 3/16" pins, in addition to epoxy.


    After boring the hole, I milled a separate piece of track material provided to me by Richard (3D Pro on SB). This stuff is a dream to work with. It appears to be a glass reinforced epoxy, that is very tough, easily machined, and adheres very well to wood with the West Systems epoxy. The specs say that it expands very little with temperature (as is the case with many composites), so growth should not be a problem.


    It allowed me to enclose the small space above the tube into an enclosed track, and to carry that enclosed track rearward to the trigger.



    A few more miscellaneous pics:


    Here's the muzzle:


    And here's the obligatory "I know you should never load a speargun out of water but I had to load one band just to show the clean sight lines" pic:


    Here's one showing the nice clean transition from where the tube ends, to where the epoxy glass material picks up at full depth:


    This is how I did the ballast. I bored a hole in the butt, behind the trigger mech. Then I used the same Forstner bit to make a temporary mold. Lastly, I sliced up the ingot into several different thickness. If I ever add a reel, or change anything else, it will be a simple matter to remove the butt pad and adjust the ballast.


    And some close ups of the handle, with sliding trigger and pushrod:


    Edited once, last by Guest ().

    I sliced the ingots on my lathe. It could have been done with a saw, but the lathe is prettier.


    It's a Riffe shaft on temporary loan from Griswold's stash, just so I had something to get it all fit up. I'll be in the market for a couple of 60" shafts.

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