popgun pete

The lithium based grease, being creamy white, seems to be less messy on your wetsuit and clothes. The black stuff on my hand is molybdenum disulphide grease, I cannot wait to get rid of all traces of it on the guns. To take those photos I must have washed my hands four times and even then I got more of it on my hands.

Any chance of a photo of the "Cernia Velox", particularly the sliding handgrip section?

Don Paul

Yes, of course, I'll get it from my kids house this Sun Peter.

Cheers, Don

__________________
''Great mother ocean brought forth all life, it is my eternal home''
Don Berry from Blue Water Hunters.
Speardiver Gear

popgun pete

Thanks Don. I just found one here on a subsequent search, but the images are too small to fathom the workings.

popgun pete

The trigger mechanism in compression spring guns is usually of the "pull down sear" type, show here. The push from the propulsion spring tries to revolve the sear lever up, like a locking pawl, and restrains the shaft. The harder the propulsion spring pushes, the better it locks. When the user pulls the trigger the short forward mounted lobe inserted into the back end of the sear lever serves to pull the sear tooth down, aided by the leverage built into the trigger arm with respect to the short length lobe engaged into the sear lever. This force from the finger's trigger pull acts at a long distance out from the sear pivot pin due to the long horizontal length of the sear lever arm giving a considerable mechanical advantage over the vertical offset of the sear tooth from the sear pivot pin. The only problem with this trigger mechanism is that when swinging down the sear tooth ever so slightly pushes the spear backwards against the action of the main propulsion spring, but the longer the sear lever arm then the flatter the arc travelled by the top of the sear tooth as it depresses to release the shaft.

This trigger mechanism was originally completely caked in dark reddish colored grease, the trigger biasing coil spring looked like a short piece of pencil it was completely filled with grease. If spring gun spearfishermen ever sought an heraldic emblem then it would surely have to be a jar of grease surrounded by tattered rags rampant and sitting on a stained field of old newspapers.

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popgun pete

For those wondering Don posted the "Cernia Velox" photos on this thread: http://speardiver.com/spearguns/2773...ection-19.html

Once again thanks Don for showing how this long gun works with its "two-stage loading".

popgun pete

The propulsion spring in a "Saetta" compression spring type gun is much longer than the barrel and has to be compressed before the rear retention pin can be inserted (there is a sort of steel piston at the front end of the spring and a muzzle restriction to keep it inside the gun). This is a pretty difficult job unless you have a tool to hold the spring down while you push the pin in, which is actually a brass bolt with a nut on the other side, and similarly to get the pin out when you want to remove the spring for cleaning. The smallest diameter on the tool (made of wood) fits inside the rear of the spring, the next diameter fits neatly into the barrel tube and the diametrical step butts up on the rear of the barrel tube with the notch in the front end making space for the brass pin or bolt. I made this one up out of an old broom handle and a piece of stainless steel spear shaft that had seen better times. You use the tool in an analogue fashion to the charging pin (hand loader), except you are working on the rear end of the spring and not at the front end of the spring as when cocking the gun. The spring (or springs; some guns use two, one left-hand coiled the other right-hand coiled with one inside the other) are quite strong and if you lose your grip then the spring will fly out with a noisy "klong" and administer grease to whatever it runs into, like your head if you don't duck out of the way in time!

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Don Paul

Nice tutorial Peter. I'm going to look for a nice long spring gun that was not ''legend owned'' so I can have a shooter. I have no problem with boat anchor guns...I can take some wt off the belt, unless I can
find some long Beryllium Copper ones.

Cheers, Don

__________________
''Great mother ocean brought forth all life, it is my eternal home''
Don Berry from Blue Water Hunters.
Speardiver Gear