105cm enclosed track composite

[azapa]

When I lived in the good ol' UK and needing machining done I signed up for a night school metalwork class. Those old teachers loved it when the student turns up with some projects in mind and happily share the machines and knowledge. They were free in those days too. Now??? Just an idea. Its amazing what an angle grinder and guide or steady hand can do though..

[alcap]

Dear Foxfish,
thank you for the replay , and forgive me for the delay in answering.
With the new attached pictures everything is clear : but let me ask one more question about Your choices.
You renounce to a monocoque ( monoshell ? ) construcion and stiffness of the body to be facilited in the making of the enclose track , or there are other reasons for ?
Anyway , what a work!!

Alcap

[foxfish]

alcap, thanks for your interest.
I use the metal to make the gun very strong that way I can use lightweight materials to make the gun look nice. I have used plastic pipe to cover the metal. The gun is not heavy & is balanced very nicely.

[alcap]

Clear , and logic.
You matched your targets, as we alla can see from the pictures .
If You will be in Italy , around Roma , bring Your fish killer w/you and youll have a free dinner as guest of mine : I already make a couple of rough finished homemade wooden spearguns , nothing that can be @mailed , but I am thinking to a new project , and some of your skill and experience will be really appreciate.
The idea is this : an enclosed track gun that fires a really short spear , with a needle point and a very light line .
In fact , everybody says that it cannot work , for the low penetration : but , in consideration of new materials actually on the market , maybe..

[foxfish]

Arr Alcap from Medfish! I have just sent you a message but never mind! I would be happy to discuse your new gun. You will find a few people on this site who will be interested in your idea. If we can help we will, please keep us informed.

[foxfish]

The next steps in the new gun build...

[foxfish]

Next....
The foam was cut back with a knife & cleaned up with coarse sandpaper, the whole gun was also roughed up with the paper & cleaned with acetone.
I then filled the area between the pipes with epoxy mixed with lightweight power, I applied masking tape & ensured the paste filled every gap.
Next....
The gun has been sanded down with the same coarse sandpaper & a little shape worked into the pipe ends.
In the third pic you can see I have installed a plastic sleeve through the handle, this is to hold the trigger linkage.

[catman]

Cool gun

Looks very nice indeed. I just have some questions.
Do you glue the two aluminium profiles? When you load the gun does it show any tendancy to wrap? Since you are using pipes(PVC?) do you have problems keeping it under water?.


Sorry for all this questions, but your design really makes me wonder why did i bought a new one insted of making one.

[foxfish]

Hi catman. Yes I glued the U section to the T section. The metal core compensates the buoyancy of the pipe but of course the gun will be balanced once finished.
The idea is for a high mass medium weight gun to alleviate recoil.
I cant imagine for one minute that the gun will flex when loading!

[catman]

Thanks for the reply, do you mind if i use some of your ideas to bild one for myself. Not exactly the same but with the same basics.

[foxfish]

Of course not my friend, I will help if I can?

[foxfish]

Next....
Now I have fitted the track. This time I have opened up the track 250mm back from the end, this will make inserting the spear a bit quicker.

[azapa]

lookin good Foxy, and thanks for advancing at the weekend instead of during my otherwise boring work week

Is that a Maorisub Spear? what length? Also, how did you bond those tubes in the sides of the "T"? Is that foam, or did you glue them and then foam fill them?

It looks doable so far, but I have no idea how you will do the trigger mech and line release.. can't wait...

[foxfish]

Trigger is mounted behind the handle & will be linked somehow with a push rod.
I had drilled holes in the T to allow the expanding foam to grip & hold the pipe in place.
It was a messy job but I filled the pipe with foam from my foam gun (you could use a disposable tin from any hardware shop) I then quickly clipped on the pipe before the foam had expanded to much. The tape held the pipe in position overnight & by then the foam had fully expanded & filled every gap including the pre drilled holes. It would take a lot of force to remove the pipes !

[Pastor]

Hows this coming along? Have you had it out yet? If so how did it perform?