My new idea: The INVERT ROLLER

[affertus]

Hallo .....

i just finished my new prototype: GLADIO.

Gladio is the name of the combat-sword of the Roman centurion.

Here i present some picture of the new system ideated.

The new concept is INVERT ROLLER.

More easy to see that to explain.

The descriptions are Italian, but the concept is certainly understandable.

Look here for the pic

Gladio: invert-roller

Here a video test

Balistica

what do you thinh about ?????

:ban :ban :duh :duh

 

[foxfish]

That is an amazing gun! Love the underwater test.

 

[Jonny250]

Super gun, looks great and a clever arrangement.

 

[Fondueset]

Very nice! what is the length of the gun - and how many meters to the target? The second shot had very good penetration! I would like to know how far it was and how thick the plywood.

 

[blaiz]

beautiful gun! seems like it has very smooth action. Is it tough to load?

 

[TOOmas]

great looking gun... i do have to admit i dont really understand how it works though... but thats just my ignorant self . well done

 

[Pastor]

I like the logic behind the gun very clever idea. How does it behave in the water?

 

[Marwan]

great looking gun... i do have to admit i dont really understand how it works though... but thats just my ignorant self . well done

me too , looks good though, seems to have very little recoil..

 

[affertus]

The recoil is minimum.

In fact in "normal" spearguns : recoil is from the mass and speed of the shaft + mass and speed of the rubbers.

In my GLADIO Invert Roller the recoil is from mass and speed of the shaft - ( mass and speed of the rubbers)

That is fact because rubbers make a movement contrary to the shaft.

Other reasons contribute to reduce the recoil.

The manoeuvrability in the water is very good because of the particular speargun's shape like a sword.

The line of vision is clean, in fact the elastic thickness decreased by loads and go below the line of fire.

The loading is easy and powerful because the elastic load one at a time, so we can give a lot more energy to every single rubber: the spearguns has the same energy of a double elastic ( about 80 kg ) , but I think with less energy dispersion.

Regarding the test firing: the target was about 4 meters ahead and the wood was compact lamellar and about 2.5 cm thick.

Here other shots made with others speargun comparing Invert Roller on the same target and with the spear of GLADIO already put on the target.

The others spearguns used for the comparison were:
-roller 90 cm
-normal circular rubber 85 cm
-double circular rubber 90 cm
-normal circular rubber 100 cm.

Gladio is 90 cm.

At the end of the video you can see the differences on the same target.

Balistica

The spear with greater penetration is that of GLADIO.

 

[azapa]

amazing looking gun, kudos for the idea and thanks for sharing it with the DB community... i can see how little recoil it has from your un-braced test shots

how does it feel/shoot in cross current? how is the balance? any fishies yet?

 

[affertus]

I did not test it at sea !!!!!

When I will test it .... I'll post the results !!!!!!!

 

[Fondueset]

Affertus - I had a thought similar to your design though I was using a cam type design with the bands on the bottom. but the idea of a long wishbone - for lack of a better term - with bands on the bottom making bands go opposite the shaft was part of it. I haven't tried to build it - mainly because spearfishing is hardly legal in my state It is very interesting to see how well it works and the gun you have made is beautiful. Looks like it might shoot 5 meters!

 

[Pastor]

You could actually rig that ad a dual band single wishbone too. You'd need arms like the hulk though to load it rofl

 

[Old Man Dave]

This is my CAD attempt to explain how it works. Top view unloaded and bottom loaded. There are two seperate bands, one each side and can be loaded one at a time.

Red is string/line/wishbone.
Green is the band.
Brown the stock etc.
Black the spear.

Make sense?

Dave

 

[affertus]

Perfect explaination "Old Man Dave" !!!!!!!!!!!!!!!!!

For the invert roller i modified also the spear with a lateral attachement :

The load of rubber is facilitate by the use of simple "tool" like in this picture:

The loading action is with to hands for every single rubber :

 

[affertus]

You could actually rig that ad a dual band single wishbone too. You'd need arms like the hulk though to load it rofl

In addition the sistem can be Implemented with auxillary bands like in this pictures.

In a first time i charge the "invert roller" rubber

and then a second rubber attached to same line/wishbone. In this manner i can load 4 rubber one at a time with about 160 Kg of energy :duh:duh:duhblackeye

Not HULK but a normal man !!!!!!!!

I also thought to 6 rubbers loaded one at a time ( about 240 Kg ) :

But I feared an implosion !!!!!!!!

:blackeye

 

[jtkwest]

The recoil is minimum.

In fact in "normal" spearguns : recoil is from the mass and speed of the shaft + mass and speed of the rubbers.

the gun looks great i do have a couple of ques.: why do you need to reduce recoil in a gun w only one band?(18mm?) i didnt think recoil is an issue in guns in that size and power range, but if it works, maybe you could use the idea in larger guns? also, you say penetration is better with roller. why? isnt penetration dictated by band power and shaft mass, not a reduction in recoil? is that true? also, according to terry maas,(blue water hunting author) the gun needs to have enough MASS to create a stable platform to project spear. it appears you may be on the right track to solving this problem another way, KUDOS to you.but basically, if i am understanding idea you are countracting recoil pushing back by creating an opposite inertia the other way, i wonder if this would work on big american blue water guns? they have alot of recoil. seems like it may make the gun innacurate, no? unless counter pressure is equal to inertia pressure. i think of it like a cannon on land, if you pushed forward quickly, just before and during firing of cannon, could you eliminate, or counter act recoil? it would seemlike yes but i question accuracy at high band power. really nice woodworking, i have been thinking about radically differnt speargun designs myself and this gun you have made is really cool

 

[affertus]

First of all sorry for the late answer.

The recoil is minimum.

In fact in "normal" spearguns : recoil is from the mass and speed of the shaft + mass and speed of the rubbers.

the gun looks great i do have a couple of ques.:
1. why do you need to reduce recoil in a gun w only one band?(18mm?) i didnt think recoil is an issue in guns in that size and power range
Because i fish in the mediterranean sea with a different approach. The reduction of recoil is important for the extreme precision ( in the mediterranean sea the fishs are smaller and diffident)

2 but if it works, maybe you could use the idea in larger guns?
Of course, in fact im trinking to build a more powerfull speargun ( double or triple rubber)

3 also, you say penetration is better with roller. why? isnt penetration dictated by band power and shaft mass, not a reduction in recoil? is that true?
True. The roller transmit a more power to the shaft with a longer course. This allow a shot more progressive than the classic rubber with less dissipation of energy and less recoil.

4 also, according to terry maas,(blue water hunting author) the gun needs to have enough MASS to create a stable platform to project spear. it appears you may be on the right track to solving this problem another way, KUDOS to you.
The mass in fundamental. In fact, in my idea of speragun with more rubber, is important to increase the mass of speargun at lest in the posterior part.

5 but basically, if i am understanding idea you are countracting recoil pushing back by creating an opposite inertia the other way, i wonder if this would work on big american blue water guns?
I dont have experience with american blue water guns but theorically and with the just application the idea must be usefull in the american spearguns too

they have alot of recoil. seems like it may make the gun innacurate, no? unless counter pressure is equal to inertia pressure.
i think of it like a cannon on land, if you pushed forward quickly, just before and during firing of cannon, could you eliminate, or counter act recoil? it would seemlike yes but i question accuracy at high band power. really nice woodworking, i have been thinking about radically differnt speargun designs myself and this gun you have made is really cool

Very thanks for the compliments !!!!!

 

[Ron Bakker]

Cool
I think Beuchat are working on something like this.

 

[nigelr]

Absolutely outstanding, affertus.
Sincere thanks for sharing your inspiration!