Sunday, August 18, 2019
  • Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 40,000+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 496,000+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,300+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

Arbalete Pneumatico Santino

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
http://www.arbaletepneumatico.com/
Santino.jpg


Here is something very different, a pneumatic speargun that looks like a timber stock arbalete. The rectangular shape (or at least the housing for it) pressurized air tank is situated under the pistol handgrip and a tube must run up inside the handle to connect to the rear of the inner barrel tube, however in this case the actual “inner barrel” is encased in a long timber stock. So in a sense it is a rearrangement of a rear tank pneumatic gun, but with a few directional changes as the air flow moves from tank to barrel during the shot as the layout is non-linear. Start pressure is 20 Bar and you can see what looks like a hand pump connection sticking out on one side of the rectangular tank block at its rear. I don't know how the trigger mechanism works, or how that mechanism traverses the pressure boundary, but if it uses a mechanical sear catch then there must be an intermediate pressure housing or block with a sear lever activating transmission pin crossing a pressure boundary wall. Wherever you have angled joints there are possibilities for air leaks if the pressurized components ever move with respect to each other, such as if the entire assembly is exposed to unexpected impacts or stresses. The rear handle pneumatic guns we are familiar with have all the components buried inside the air tank, whereas the classic layout mid-handle pneumatic guns relied on the mid-handle body section as a connector, but with the inner barrel tube running the full length of the gun the inner barrel was still the structural member holding those guns together against the air pressure trying to blow them apart. Only the early mid-handle versions had the barrel projecting forwards from the mid-handle body with the rear tank containing nothing but an air tank. Thus this “Arbalete Pneumatico Santino” is somewhat the same, however it would be interesting to learn more about the internal mechanical layout.
Santino air tank.jpg
 

Diving Gecko

shooter & shooter
Jun 24, 2008
1,268
309
138
Shanghai
OK, so the pics on his facebook profile are a bit better in resolution.
I can glean that a piece of slightly bigger tube is welded onto the back of the shooting barrel. I can not see the underside of it, but it must have to do with the trigger.

Also, the external air reservoir is pretty simple. It is basically four lengths of steel tubing welded into a square frame. In the middle of it, another tube (comprised of two short tubes welded at an angle) rises up towards the gun to form the handle plus it is part of the reservoir and leads the air into the shooting barrel.

I suspect the wooden block under the reservoir is for buoyancy purposes.

And Pete is right, it is a regular air inlet pump valve on the left side of the reservoir.

The gun is rigged for front tied shafts but can't tell if it is a vacuum muzzle or not. The shock absorber must be internal (sitting inside the shooting barrel). Unless, of course, there is no piston at all.
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Translation by Bing of the Usage instructions, after a few repairs!

Usage recommendations Pneumatic Spearguns rifle:
-Never exceed the precharge pressure of 25 bar
-Do not cock the rifle out of the water.
-Do not shoot out of the water.
-Do not point the gun at other people (even if it is unpressurized).
-Do not turn the shaft after placing it in the rifle.
-Unload the gun before you get out of the water.
-Run the air in the tank only if preload is evident in poor propulsion; Do this only after you have downloaded all the air from the tank. Or add the pressure already posted previously in the tank with the pump that you would like to add, but not exceeding 500 pump strokes count.
-For preload only use air pumps for air spear compressed.
-Do not disassemble any part of the gun if you do not have to download completely compressed air through the valve on the side of the tank, by kicking pressing punch the centre thereof.
-If you disassemble any parts of the rifle, you will lose your warranty envisaged; then we suggest you contact the company for any clarification.
-Do not expose the gun to heat sources.
-Do not use the gun improperly.
-After use guard it jealously away from children or inexperienced persons.
-Do not use spears or traditional bent shank or slightly spears wrong, because it could compromise its correct functioning and damage the internal parts of the rifle.
-Be careful checking in every fishing trip that the rifle is in good condition and It has no cracks or unusual alterations; in the event, provide to download all the air contained in the tank and after telephone contact send it for repair.
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
And ditto for the general instructions.

Suggestions of use Pneumatic Spearguns rifle:
-We recommend the use of the rifle at pressures ranging from 20 to 24 Bar precharge ideals, for a perfect balance in the balance between power and accuracy.
-The rifle should be washed under running water after each fishing trip and ethanolamine (lubricate?) in all mechanical parts active.
-The Speargun is perfectly aligned in its parts, then avoid rub or wipe in rocks so as not to spoil the barrel and lose the trim, alignment and accuracy.
-Do not use crooked or slightly bent spears because it would compromise the proper functioning of the gun.
-Use only "free" shafts without final tang.
-Before servicing by removing any part of the rifle, make sure you have done the drain any compressed air through the valve at the base of the rifle.
-To make the compressed air pre-charge, use a hand pump type "Mares". Through a special valve located in the tank, run a drain pre-empted by the manufacturer, using the full air valve with a awl. Performed then, up to 500 pump strokes starting from a pressure inside of the tank completely empty.
-Back-load pump only and exclusively if there is an obvious lack of power in the shot.
-If you notice any abnormal in appearance or in the operation of the rifle use it, download the compressed air tank and send him back to the manufacturer, subject to information provided by telephone, describing the problem.
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Now some time ago some people here were expressing the desire for a pneumatic gun with the barrel on top of the tank and although I cannot remember who it was exactly it seems to me that this is what they wanted. No muzzle relief ports (that I can see anyway) and the use of bare tail spears would appear to indicate a vacuum barrel system, probably one based on "O" rings as there is no need to pass a spear tail stop diameter. The maximum of 500 pump strokes using a Mares hand pump to reach 25 Bar gives us an idea of the tank capacity as you only need to look up what Mares model hits 25 Bar with 500 strokes of the pump. The barrel on this "Santino" gun will be longer, but that will not really affect a comparison as to what the tank size will be. From the Mares "Sten" table the "Santino" seems to be between a "Ministen" and a "Medisten" in terms of its tank volume which seems on the small side given its long barrel.
Sten Pumping Table.jpg

Now I remember, it was "Old Man Dave" and "foxfish" in the "new Omer pneumatic!!!" thread who expressed a desire for the market to produce such a gun, refer their posts #75 and #76 on that thread (which was about the then new "Airbalete").
 
Last edited:

Diving Gecko

shooter & shooter
Jun 24, 2008
1,268
309
138
Shanghai
Me too, me too, haha. I also have expressed how disappointed I have been that manufacturers still have not pushed the barrel higher up.
Granted, I did not think about separating the tank and barrel I do think that is a smart way to do it.
Personally, I like the idea behind this design but I see it more as a small and precise Mediterranean sniper gun. I think in its current design, there are just too many options for tangles. The open trigger guard (though popularized by Abellan) and the tank itself are obvious potential places for snags. Also, the handle needs some work.
But cudos for making this gun in the first place:)

BTW, it was a brain fart on my behalf when I thought that perhaps this was a piston-less design. I reckon you can't have that in a traditional oleo (vs. e.g. a compressed CO2 gun) which I already knew the gun was when I wrote that;-).
 
Last edited:
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
I think that the "new" Cressi-Sub "Saetta" pneumatic has a high barrel, but you can see the downside to having the connecting bar (the inner barrel) very high up as the pressure bulkhead ends of the gun tend to "banana". To some extent you could see that happening with the "Mirage" as well. Actually the height of the inner barrel is going to be changing by less than half the radius of the tank, if it is still going inside the tank, and that is not a big amount to compensate for. The "Cyrano Evo" pushed the inner barrel up to create space for a larger transfer port.

At least in the "Santino" the barrel is not going to be clamped onto a tank as you would have to do otherwise if the gun was like the early "Air Balet", which I have since discovered was of 1969 vintage and 2 years after the "Sten". I have seen a few examples held by collectors, but the market did not seem interested in such an ungainly looking gun. At least the "Santino" looks the part and we have to remember that it is a custom builder effort and not a production gun churned out in the hundreds if not thousands.
Cressi saetta handle.jpg
Cressi saetta muzzle.jpg
AIR BALETT R.jpg
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Here are photos of an "Air'Balett" which belongs to a French collector, in fact he took the photos. Note the primitive "outrigger" trigger and the fact that the gun still has its paper stickers! That may indicate a lack of sales success if a new "old stock" model could be picked up years later.
AIR'BALETT lhs.jpg
AIR'BALETT rhs.jpg
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Just reading through the latest material it seems that the gun now has a smaller tank volume and a larger compression ratio than it had before. Previously charge pressure was 25 bar, now it is 10 bar with a maximum of 12 bar. This will make for a less powerful gun than it was before as although cocked to shoot pressure is probably the same, but final pressure as the spear departs the muzzle will be lower.

Santino models table new.jpg
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Instructions for use pneumatic Arbalete rifle

Model "Superlight"


-The use of the shotgun allows pre-charge pressures ranging from 9 bar (130 psi) to a maximum of 12 bar (174PSI);
-For the insertion of the rod and the loading of the rifle, place it on the instep between the stock and the rifle tank; Hold with one hand the head and with the other, using the special load, insert the rod inside the rifle until the trigger is engaged that will determine the bottom stroke of the rod. (For more explanations you can view the video of the upload on the site: www.arbaletepneumatico.com
-The insertion of the loading rod is the most demanding and dangerous part. Do not leave the rod until you have reached the piston stroke bottom and the consequent coupling of the trigger.
-For a good operation over time, wash the rifle and its parts with running water. Then lubricate all active components of the product with silicone blooms.
-It is possible to regulate the hardness of the line release; By dismantling the reel and paragrilletto you will find the adjusting nut consisting of a rubber, a washer and a nut, which screwed up will expand the rubber that will regulate the hardness of the release. (It is advisable to avoid harsh adjustments).
-The underwater rifle is perfectly aligned in its parts, so avoid banging or rubbing it in the rocks so as not to ruin the barrel and lose the trim, alignment and accuracy.
-Do not use crooked or slightly bent rods as they would compromise the safety and proper functioning of the rifle.

Do not use rods or shankets(?) other than those supplied by the manufacturer.

-Do not intervene by dismantling any mechanical part of the rifle;

-Make sure there are no anomalies in the operation before each fishing trip.

-Only carry out the pre-charge pumping if there is a clear lack of power in the shot and never exceed 12 bars (175PSI). Carried out with a special column pump for racing bicycles, equipped with pressure gauge, in order to keep the pre-charge pressure under control, which must not exceed 12 bar (145 psi).

-If you notice any anomaly in the appearance or operation of the rifle do not use it, immediately discharge the compressed air of the tank and send it back to the manufacturer, after a telephone notice, describing the problem.

-The rifle has a two-year warranty. It decays if you have an improper use, other than that dictated in the instructions for use or if you disassemble integral parts of the underwater rifle.

-The material of normal wear is not guaranteed in use.

-Use the various interchangeable drums on the machine body through the special screws.

-The stem, as an accessory, is not guaranteed but replaceable at the user's request.

-Use the various specific drums, available in the catalogue for every type of fishing you wish to carry out. Facilitating movements and dynamic balancing in complete safety.

-Do not rely completely on the pressure gauge installed in the tank if you want to disassemble any part of the rifle. Be sure to download it through the special valve in the tank.

-The valve must be unlocked, partially unscrewing the special cap and pressing firmly until residual air is released into the tank. Immediately afterwards you can proceed to a new preload.

http://www.arbaletepneumatico.com/VID - Promo.mp4
 
Last edited:
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Some photos of the gun in action taken from the promotional video.
Santino Pneumatic in action.jpg

Here the cocked to shoot gun slowly sinks to the bottom after being released.
Santino cocked to shoot and slowly sinking.jpg
 
  • Like
Reactions: Zahar
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
If you look at this video then you will see that the spear now has a line slide and a stop diameter on the spear tail.

Santino pneumatico spear with line slide.jpg

Great workshop with a gun test tank!
 
Last edited:
  • Like
Reactions: Zahar and foxfish
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Pressurizing the gun, which also some of the construction detail.
Arbalete Pneumatico works.jpg

When pulled the trigger pushes down on the rear of the “para trigger” which at its front end lifts up and my guess is that front end pushes upwards the 1.5 mm transmission pin that tips over the usual pneumatic sear lever to release the piston and shoot. If the second lever is the "leverage" listed in the parts list then the "para trigger" may be something else, plus the gun has a line release which I think is friction loaded with a rubber washer. That would make it a passive line release, but those are not usually teamed with reels as snugging up the line with the reel can pull the line free.
 
Last edited:
  • Like
Reactions: Zahar
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Here are photos showing the inner works and them being fitted to the outer stock which can be quickly interchanged with other outer stock finishes with just a rear slide of the innards and a press with a click to lock the barrel in at the muzzle, it is a very slick operation.
Santino gun inner works.jpg

Santino fitting innards to outer stock.jpg
 
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Seeing as wide and curvy stocks for timber band guns are currently in vogue, another variation on this interesting gun which would give back some of its tank volume would be to place two cylinders either side of the barrel that were only of a limited length and diameter, but every bit of extra tank volume helps to provide a compression ratio for the gun where the propulsive force along the barrel will be more constant. However by building it as he has done the slim barrel is easily inserted and withdrawn from the gun and the construction is excellent and of high quality.
 
Last edited:
OP
OP
popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
3,035
590
153
Australia
Given the line slide and spear tail stop I think that it must be a wet barrel in this latest version, plus there is no mention of muzzle seals in the spare parts catalogue as shown below.

Spare Parts Catalogue:

-Stainless steel head (muzzle)....................................... E. 20.00

-Teflon tape of seal parts.................................................. E. 5.00

-Spear Tahitian.. ........................................................... E. 40, 00

-Line Slide Kit................................................................. E. 10.00

-Wooden trunk with livery............................................. E. 130.00

-Barrel lock coupling....................................................... E. 10.00

-Stainless steel Para-trigger........................................... E. 30.00

-Release box.................................................................. E. 40.00

-Stainless steel trigger and leverage..............………..... E. 30.00

-Accommodation black Teflon cane.............................. E. 60, 00

-Stainless steel brackets Teflon block............................ E. 15.00

-Complete O-ring Kit....................................................... E. 15.00

-Stainless steel Bolts Kit................................................. E. 30.00

-Stainless steel screw Kit for wood....................................E. 3.00

-Tank lock..................................................................... E. 160.00

-Air loading valve............................................................ E. 10.00

-Piston D. 11 mm............................................................ E. 10.00

-Release tooth Kit (sear lever)........................................ E. 10.00

-Coupling Kit + PIN 1.5 mm (transmission pin)............... E. 10.00

-Barrel D. 11 mm............................................................. E. 70.00

-Specific oil SAE 20......................................................... E. 10.00

-Pressure gauge.............................................................. E. 50.00

-Non-slip tape for handle................................................. E. 15.00

-Complete reel................................................................ E. 60, 00

-Wood screw for reel....................................................... E. 10.00

-Polycarbonate shell reel................................................. E. 30.00

-Complete bracket for reel connection............................ E. 30.00

-Bolt Kit........................................................................... E. 10.00

-Aluminium inserts Kit for reel......................................... E. 15.00

-Full camera bracket....................................................... E. 30.00

-Adhesive Kit (complete)................................................ E. 25.00
 

tromic

Well-Known Member
Aug 13, 2007
1,551
149
153
Croatia
I suppose so too. There are neither water escape ports as usual. Water must escape forward with the spear...
Next I suppose that the compression ratio is probably CR > 2.5
I made an estimation using my speed-energy calculator. For the longest model speargun, 120 cm a suppsed the working couse of the piston to be 115 cm (maybe it is less, 110 cm?). On 11.76 bar (12 at) with CR=2.5 if the spear weight had been 361 g the initial speed of the spear would be about 34 m/s.
Initial loading effort 12 kgf and final loading effort about 29 kgf. I did not take in calculation water column around the shaft so the result might be a bit worse.. (The Force on the spear on shot is the average force)

54257