Very Interesting Damascus Topic Thread.

[Dean Romig]

Originally Posted by Francis Morin

The basic filler rod, regardless of the diameter, in SMAW electrodes (with the exception of the 300 and 400 Stainless grade electrodes) have the same metalurgical analysis- 1/8", 5/32", etc in the 6011 series- what would make a 1/8" dia (the bare end that is placed in the stinger) 6011 AWS rod differ from a 1/8 6013 rod is the chemical composition of the flux- both rods, if properly applied, will give a mean tensile of 60,000 psi minimum as stress relieved-

Yeah, I got all that and think I understand it, but....


:

If, on the other hand, you mean tensile/ a correspondent to ductility in some ferrous metals, in a steel rod- such as re-bar or other structual reinforcement applications, the reading may differ- but the fabrication grade steels ( angle, channel, I-Beam etc.) used in coded construction applications today will average 53,000 psi tensile before rupture- think of the tensile test as a giant taffy pull with calibrations to read in PSI-

....so, a 1/8" piece of 6011 rod will support twenty-five tons before stretching?? I don't believe it.... Am I missing something? I'll be ther first to admit that I have no background in metals whatsoever so I'm quite willing to learn.... but I didn't just fall off the turnip truck so tell it to me in a way that I can believe.

[Double Trouble]

Dean:

If my math is correct, a 1/8" dia. rod of 60,000 psi tensile strength steel will support 736 pounds before it begins to undergo plastic failure (ie: permanent stretching). The bar will strech before this point (elastic, not plastic), but will return to the original length upon removal of the load.
Ultimate tensile strength is the load that results in the piece actually breaking.

[Austin W Hogan]

Back to the original topic' if someone can find a good wall thickness gauge we can probably measure 20 or more barrels at the HQ tent at Pin Tail

Best, Austin

[Old and Reliable]

That is why the welding rod is rated at about 10% higher that the UTS of the base metal(s) being joined by the welding process- SMAW- MIG (Metallic Inert gas) wire welding- most of the .030- .050 range filler wires used (with copper flash coating for greater current conductivity) at at a 70,000 UTS range- I don't know John Mazza from Adam's offside ox, but I'll bet he is a student of Hooke's Law--

Austin- I suggest you contact PGCA lad Jon Bosford in Ann Arbor, MI- he was at both Da Yooper shoot and the recent Lapeer side-by-event- if he is coming out to Pin the Tail on Da Point in Sept- he'd be your "go to guy" on barrel wall thickness gauging-

[Double Trouble]

Francis:

The engineering education occasionally pays off...

(It also makes me over-analyze everything !)

[Old and Reliable]

Hooke's Law, Occam's Razor, the Pythagorean Theory, Newton's Laws of Gravity- all bow down at the Altar of Murphy- when it can go wrong, it will- Three disciplines intrigue me to no end (I barely got out of HS and into the USMC- many years ago now) they are: Classical Music, Architecture and Metallurgy- all involved with higher strata of Math- I have nothing but respect for the engineers who design and then oversee the build- as we used to say in the Fab Shop[- "If they can draw it on paper, we can build it in metal to print- time after time"__

[Double Trouble]

Francis:

Likewise, I have encountered some fine craftsmen with amazing insight & skills. In fact, I have the honor/pleasure of working with such a person on a major project in a few weeks. It's times like this that I really enjoy coming to work !

[Drew Hause]

Damascus Mythology
https://docs.google.com/Doc?id=dfg2hmx7_220dpc9nsck

Damascus Quality
https://docs.google.com/Doc?id=dfg2hmx7_22ddqshmdq

The Double Gun & Single Shot Journal "Finding Out For Myself" by Sherman Bell Vol 17: Issue 3 (Autumn 2006) p. 12, Vol 17: Issue 4 (Winter 2006) p. 28, and Vol 20: Issue 3 (Autumn 2009) p. 108

Do shotgun barrels become "brittle" over time?
http://doublegunshop.com/forums/ubbt...599#Post190599

H.P. White Laboratory, Inc. in Maryland will proof Twist or Damascus barrels for $420 per Shooting Sportsman March/April 08'
www.hpwhite.com 410-838-6550
I have not used their service, and would be most interested in hearing from someone who has.