old wood gun remodeling project

well i have an older jbl sawed off wood magnum speargun that was sitting at my parents garage for a while. i have decided to do some remodeling and make it a little longer.

with my friends getting longer guns for the channel islands camping trip this may i too had the bug to get something longer but fifnancially cannot splurge for a new gun right now. so i decided to modify this one i have. total for the modifications will be around 120.00 including new shafts.

so far i have done:

- ordered 2 shafts from ray odor / 48" with 3" flopper

- got a JBL truglide track which will be used on the Ti tubing.

- cut the stock of the gun to drill it for the 1" titanium tubing to lengthen it

- made the delrin open muzzle, i am waiting for the ti tubing to show up in the mail so i can size the plug end properly. once thats done i can epoxy in the shooting line pins.

- have 5 feet of 5/8 rubber for the bands and dacron line for the wishbones.

West Marine has a lot of good stuff.

here is a photo of the delrin muzzle i machined last night for 3 bands.

For drilling of the original JBL mahogany wood stock of the gun I am using my metal lathe. The drill bit goes into the headstock and the wood will be leveled and angled in the crossslide while i use the handwheel to basically push the wood onto the brad point drill bit. kind of like this:

for the barrel of the gun i chose the extension out of titanium with .036 wall and 1" OD for strength and weight reasons. I was also thinking of going to carbon fiber but the tubing i found at a price i can afford was a 1" ID and I didnt want to hassle with looking for a big wood bit to fit the OD of that stuff.

The Ti tubing is a total of 20 " and will be going into the gun 5-6" and held in there with west system epoxy.

i will be reinforcing the side of the original mahogany stock of the gun with teak supports running up and down both sides of the gun. not so much as wings but as structural supports secured on with stainless wood screws and epoxy.

I chose to use the whole handle / trigger assembly because i dont have enough wood working experience to be making stuff like that and the parts are pretty pricey to buy piece by piece.

Alright John! Do us spearfishing-no-nothings a favor and document w/pic's. You got some mad-skillz and I know I could learn a ton about spearguns/fishing from you. I've always wanted to try and I know with this crew I will eventually have the pieces fall into place.

You were reading my mind

You were reading my mind

hi randall, i will take more photos as i am working on this. this is my first time really modifying anything of wood so i need to make sure i practice on scrap wood first; )

here is my buddy chris' website, he makes spearguns in san carlos and they are works of art. if i get cold feet about drilling into my mahogany gun stock i am going to go to him for the drilling!

check this site out:

http://seasniper.com/

i'll take more photos as i go along 

john

i guess i can try drilling the wood myself but i'll practice first. i think i need to get one of these to use when drilling with the lathe, im not real good at stuff like this.:

 I know finding center on something not perfectly round or square can be difficult. If you drill before you cut the stock that will keep holes lined up.

I know finding center on something not perfectly round or square can be difficult. If you drill before you cut the stock that will keep holes lined up.

i hear you: )

the tricky thing is that this stock is the original stock made of mahogany. i guess i am lucky that the wood is in pretty good shape and that its cut flat on both sides.

i have to position the bit so it drills a hole in the right place on the stock so that when i install the Ti tubing with shaft glide track, both tracks on the wood and tubing will be even.

John,

I'd not use a level. I'd use an indicator to first dial in the surface that will be used to clamp the workpiece. Then I'd dial in the horizontal surface of the workpiece, making sure that the workpiece is centered vertically with the headstock. Centering the workpiece horizontally will be cake, as you can use the cross slide.

Regards,
Scott

John,

I'd not use a level. I'd use an indicator to first dial in the surface that will be used to clamp the workpiece. Then I'd dial in the horizontal surface of the workpiece, making sure that the workpiece is centered vertically with the headstock. Centering the workpiece horizontally will be cake, as you can use the cross slide.

Regards,
Scott

Scott, thanks for the advice. I hope the indicator on my lathe is good. I will take this advice and test on a piece of wood dowel before running the speargun stock into the bit: )

Thanks!

John

I have a metal sawed off magnum with a pretty beat up barrel that I'd like to do a similar procedure with, though probably I'll replace the barrel entirely with a longer one.  Maybe shorten the original (it's worst at the ends) so I can use it as a 'linda mar special'. 

My grandfather makes bowling alley parts out of delrin (or at least he used to, he's pretty active in retirement) so I may be able to get some scrap from him next time I'm in MN.  Maybe if I showed him the price of speargun muzzles he'd say 'screw bowling alleys' and make those instead. 

I have a metal sawed off magnum with a pretty beat up barrel that I'd like to do a similar procedure with, though probably I'll replace the barrel entirely with a longer one.  Maybe shorten the original (it's worst at the ends) so I can use it as a 'linda mar special'. 

My grandfather makes bowling alley parts out of delrin (or at least he used to, he's pretty active in retirement) so I may be able to get some scrap from him next time I'm in MN.  Maybe if I showed him the price of speargun muzzles he'd say 'screw bowling alleys' and make those instead. 

thats cool, i can imagine a lot of delrin being used for bushings and other stuff at a bowling alley. Say, when you want to do the speargun project let me know and i'll make a muzzle to fit the barrel of your jbl barrel. wont take but a few minutes and a little delrin i have. then you just have to position it and  marine epoxy it in the gun.

: )

john

Well the shafts arrived safely in a PVC tube from Florida. Ray Odor diving services has freeshafts for 25.00 each and they are drilled and have a flopper installed. The bummer part is that they are 2 band shafts and i will need to make a 3rd notch for 3 bands should i decide to use all 3. otherwise the flopper and spring stainless shafts are the best deal on this planet as far as i could find. they are 5/16th x 48", now i just need a gun for it: )

here are some pictures of the other parts i have so far...

i need some time to work on this soon.

dang it to HELL! i just found out that the Ti tubing I ordered is the thinner 1" OD and .021 wall tubing. And I tried calling the guy who sells this stuff in Missouri and he was grumpy about selling me the right one on top of it. i think he is just lazy.  So what I decided to do was to buy a length of carbon fiber tubing from another guy in san diego. It was 17.00 for a 1" ID CF Tube with a wall of .030 and 20" of that stuff. I plan on cutting it 5" short of the Ti tubing and epoxy it over as a sleeve for more rigidity. I am going to see how it works out and tes a piece thats glued , if that bends or dents then i will get the thicker Ti tubing. I am just concerned about where the .021 Ti will go into the wood stock. i dont want that to be the weak point.

I think i should get that tubing anyhow. i hate doing a project and then running into a missing link.

john