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Hybrid guns

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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StretchArmStron

New Member
Jan 19, 2004
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Got the titanium tubing...

need to figure out the specs on what size block to use? And after getting the block cut how to make a good strong mount from the tubing to wood.

PM'ed another member w/ no reply yet...

any opinions/help is very welcom.

Thannks!

John.
 

defofthecrown

Morone saxatilis
Mar 8, 2003
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I asked Sven about his hybrid(which looks sweet) and he said the attachment was approximately 4" of tube epoxied into the wooden block (I think).
 

defofthecrown

Morone saxatilis
Mar 8, 2003
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Ti vs CF is the common 'theme' in discussions when it comes to hybrid guns (Thanks Daryl). However these 'exotics' may be more hype than functionality. when you search for information on these materials the applications are for model airplanes, racing bikes, NASA, kayaks, etc. What do all these fields have in common? The need for low weight, or more specifically a high stength to weight ratio.

The benifts to Carbon fiber being very small deflection over the length and very small compression. In other words it's stiff. It will have minimal barrel flex in our applications. It is also relatively non-reactive in the harsh (battery-like) salt water atmosphere. Any one who disassembles their aluminium guns w/ stainless steel hardware will appreciate this. The disadvantage being a compromised impact resistance...oh yeah and price!!!!! A CF barrel w/ a few to many dings won't start to deform and bend like metal. It will not fatigue over time but will instantly, and by all accounts, impressively fail *poof*.

What does this high cost buy you? Less weight. Sounds good, but it isn't. As we all know thanks to Iyadiver and our 12th grade physics teachers every action produces an equall and opposite reaction. Ergo one needs to ballast a gun to produce maximum shaft velocity, enter bulky side stocks on bluewater guns and 'hybrid euro' guns.

Titanium on the other hand is harder to work with, also expensive and reactive w/ other metals (like ss hardware). Cost aside the concensus among most spearos is CF over Ti.

The benefits , as I understand, of the hybrid guns are less recoil w/ more power, and a stronger american square-notched trigger mech to handle this power. So if one of the benefits is dependand on MORE weight, why are we spending exhorbitant amounts of money for LOWER weight materials like CF or Ti.

Solution: A hybrid gun should have a barrel made from plain fiberglass. Fiberglass roven woven can be obtained for a fraction of the cost of CF or Ti and will produce equall stifness when a thicker walled tube is layed-up. This not only saves money, but (albeit minamally) decreases the additional amount of ballast to be added to the stock. Not to mention that a thicker walled tube would be more impervious to the occasional dent or scratch w/out risk of failure. This is also a better choice than thicker walled aluminuim or SS b/c fiberglass is not reactive. The tube could also be produced w/ permanent fiberglass interior caps to insure a water tight barrel. Not to mention that a homemade barrel for your home made gun (and a homemade muzzle :) ) is more gradifying.

So why do we use CF or Ti? Because it sounds better.
 

StretchArmStron

New Member
Jan 19, 2004
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chris you are wierd....I have titanium....so I am building a titanium hybrid...

when you build your next gun...oooh wait you've yet to build one! ahahahaha...


Gimme a shout sometime dood.
 

ajwaverider

New Member
Jan 3, 2004
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Just some info on TI tubing that I got from the maker of the tubing I have.


SEAWATER - GENERAL CORROSION
Titanium resists corrosion by seawater to temperatures as high as 500 degrees F (260 degrees C). Titanium tubing which has been exposed to seawater for many years at depths of over a mile shows no measurable corrosion. It has provided over twenty five years of trouble-free seawater service for the chemical, oil refining and desalination industries. Pitting and crevice corrosion are totally absent, even when marine deposits form. The presence of sulfides in seawater does not affect the resistance of titanium to corrosion. Exposure of titanium to marine atmospheres or splash or tidal zones does not cause corrosion.

EROSION
Titanium has the ability to resist erosion by high velocity seawater. Velocities as high as 120 ft./sec. cause only minimal rise in the erosion rate. The presence of abrasive particles, such as sand, has only a small effect on the corrosion resistance of titanium under conditions that are extremely detrimental to copper and aluminum base alloys. Titanium is considered one of the best cavitation-resistant materials available for seawater service.

STRESS-CORROSION CRACKING
TIMETAL 35A and TIMETAL 50A are essentially immune to stress- corrosion cracking (SCC) in seawater. This has been confirmed many times. Other unalloyed titanium grades with an oxygen content greater than 0.25 wt.may be susceptible to SCC under some conditions.

CORROSION FATIGUE
Titanium, unlike many other materials, does not suffer a significant loss of fatigue properties in seawater. In fatigue- limited applications, Boiler Code criteria or actual in situ fatigue testing should be considered.

CREVICE CORROSION
Crevice corrosion of unalloyed titanium may occur in seawater at temperatures above the boiling point. TIMETAL Code-12 (Grade 12) and TIMETAL 50A Pd (Grades 7 and 16) and 35A Pd (Grades 11 and 17) offer resistance to crevice corrosion in seawater at temperatures up to 500 degrees F (260 degrees C).

GALVANIC CORROSION
The Coupling of titanium with dissimilar metals does not usually accelerate the corrosion of the titanium. The exception is in highly reducing acidic environments where titanium may not passivate. Under these conditions, it has a potential similar to aluminum and will undergo accelerated corrosion when coupled to other more noble metals.

Table 1 (see page 10) gives the galvanic series in seawater. In this environment titanium is passive and exhibits a potential of about 0.0 V versus a saturated calomel reference cell (SCE) which places it high on the passive or noble end of the series.

For most environments, titanium will be the cathodic member of any galvanic couple. It may accelerate the corrosion of the other member of the couple, but in most cases, the titanium will generally remain unaffected. Figure 2 shows the accelerating effect that titanium has on the corrosion rate of various metals when they are galvanically coupled in seawater. If the area of the titanium exposed is small in relation to the area of the other metal, the effect on the corrosion rate is negligible. However, if the area of the titanium (cathode) greatly exceeds the area of the other metal (anode), severe corrosion of the other metal may result.

Because titanium is the cathodic member, hydrogen may be evolved on its surface proportional to the galvanic current flow. This may result in the formation of surface hydride films that are generally stable and cause no problems, If the temperature is above 176 degrees F (80 degrees C), however, hydrogen may diffuse into the metal and cause hydride-related embrittlement.

In order to avoid problems with galvanic corrosion, it is best to construct equipment of a single metal. If this is not practical, use two metals that are close together in the galvanic series, insulate the joint or cathodically protect the less noble metal. If dissimilar metals are necessary, and since titanium is usually not attacked, construct the critical parts from titanium, and use large areas of the less noble metal and heavy sections to allow for increased corrosion.
 
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ajwaverider

New Member
Jan 3, 2004
422
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John you can build the stock to the dimentions that work for you there is no preset measurments. Just remember you want it is as lowprofile as possible but have to leave enough wood for proper
support of the barrel.
 

ajwaverider

New Member
Jan 3, 2004
422
30
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funny

Originally posted by StretchArmStron
chris you are wierd....I have titanium....so I am building a titanium hybrid...

when you build your next gun...oooh wait you've yet to build one! ahahahaha...


Gimme a shout sometime dood.
 

defofthecrown

Morone saxatilis
Mar 8, 2003
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AJ-***SEAWATER - GENERAL CORROSION
Titanium resists corrosion by seawater to temperatures as high as 500 degrees F (260 degrees C). Titanium tubing which has been exposed to seawater for many years at depths of over a mile shows no measurable corrosion. It has provided over twenty five years of trouble-free seawater service for the chemical, oil refining and desalination industries. Pitting and crevice corrosion are totally absent, even when marine deposits form. The presence of sulfides in seawater does not affect the resistance of titanium to corrosion. Exposure of titanium to marine atmospheres or splash or tidal zones does not cause corrosion. ***

Neat...so your using titanium hardware too right:hmm ? In a saltwater environment two dismilar metals in contact will create a circute where by the 'lesser' of the two metals will become a 'sacrificial' anode. Again, if I look at my JBL the SS harware is fine b/c it's less reactive or more 'noble' than the aluminium. Therefore the aluminum is degraded/oxidized. The same can be seen w/ sacrificilal zincs on boat hulls. They, as per their design, disappear while the engines etc on the boat stay intact.

I have no doubt your Ti tube will last forever:) it's your hardware that I'm worried about.

Of course it will be fine for years to come too, but i was a little board and looking to instill a touch of contraversy. The deal is still on once I finish my mold -if your still in :D .
 
Last edited:

defofthecrown

Morone saxatilis
Mar 8, 2003
298
30
0
42
AJ-***SEAWATER - GENERAL CORROSION
Titanium resists corrosion by seawater to temperatures as high as 500 degrees F (260 degrees C). Titanium tubing which has been exposed to seawater for many years at depths of over a mile shows no measurable corrosion. It has provided over twenty five years of trouble-free seawater service for the chemical, oil refining and desalination industries. Pitting and crevice corrosion are totally absent, even when marine deposits form. The presence of sulfides in seawater does not affect the resistance of titanium to corrosion. Exposure of titanium to marine atmospheres or splash or tidal zones does not cause corrosion. ***

Neat...so your using titanium hardware too right:hmm ? In a saltwater environment two dismilar metals in contact will create a circute where by the 'lesser' of the two metals will become a 'sacrificial' anode. Again, if I look at my JBL the SS harware is fine b/c it's less reactive or more 'noble' than the aluminium. Therefore the aluminum is degraded/oxidized. The same can be seen w/ sacrificilal zincs on boat hulls. They, as per their design, disappear while the engines etc on the boat stay intact.

I have no doubt your Ti tube will last forever:) it's your hardware that I'm worried about.

Of course it will be fine for years to come too, but i was a little board and looking to instill a touch of contraversy. The deal is still on once I finnish my mold -if your still in :D .
 
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