Casting Lines or Welding on Cannons?

[Santee1821]

Question #1 - On roughly finished cannons, are lines ever visible where two sections of a mold came together?

Question #2 - What on earth are the lines running down the sides of these two cannon-shaped-objects which were carried aboard USS Constitution circa 1907 to 1927?

A bit of background - I was intrigued by a display of surplus USN cannons and shells placed at the University of Maine with the help of a G.A.R. post in 1932. The display is a pair of 8-Inch MLR Conversions of 11-Inch Dahlgrens and a pair of cannons which had been carried aboard USS Constitution. I've worked with a student who sent me a number of pictures.

I am mostly interested in the Dahlgrens, and the story of the placement of the memorial is an interesting one that I will share more on in the future.

But those 24-pounders... or whatever they are...

I had read that a set of cannons were manufactured at the Boston Navy Yard circa 1906 for USS Constitution's partial refit, and a new set was cast circa 1926 for her major overhaul. It is the 1926 set that is still aboard. I had wondered why a new set was really needed until I saw the photos of the "cannons". I think I could hear a screaming gunner's mate as I looked at the photos.

Are those casting lines? Are those welding lines? I had read that the refit of 1906 was done as inexpensively as possible, but those are awful.

The 8-Inch MLR Conversions:

The shipment order from BuOrd. Decorative purposes only... no kidding!

 

[Rhea Cole]

First off, those definately are not weld lines. For a host of reasons that isn't it.

The mold lines in the display cannon are not surprising. They are not manufactured to the same finish as operational cannon would be. The reason for a smooth finish is not just for appearances sake.

Many cannon were very elaborately decorated. Eventually, it was established that even minimal right angle embellishments were the source of fatigue cracks.

This is a bronze Ames model one 14 pound rifle.
Outwardly it is identical to an 1841 model six pound smoothbore.

The Ames model 2 rifle shares the elegant smooth lines of the 3" ordinance rifle.

Not so streamlined in shape, this Waird rifle shares the smooth finish.

Present day display cannon are often cast fiberglass. They can be so perfect in appearance that only a tap with a knuckle will tell what they are made of.

The examples of display only castings are of a rough finish. However, there is nothing wrong with that.

When the Constitution was converted to a barracks, all her original guns were recycled. Like the originals, the present armament was based on a 32 pound siege gun abandoned by the British.

Really interesting link to how a 40 MM saluting gun was inserted into the cast iron display cannon on the Constitution. It is an eye opener.

Link:

Firing a Salute - USS Constitution Museum

In the waning days of the USS Constitution‘s 1973-1975 restoration, Commanding Officer Tyrone G. Martin, investigated the possibility of retrofitting for saluting purposes two of. . .

ussconstitutionmuseum.org

 

[DixieRifles]

BTW, a "mold line" is not just seen on a casting. Forgings also leave a seam.
This photo is from a website that forges aircraft landing gear components using a 50,000 Ton hydraulic press. I cant say you will see that on Civil War cannons.

Operator is setting up forging to locate the center line and planes before starting to machine it.

 

[Belfoured]

First off, those definately are not weld lines. For a host of reasons that isn't it.

The mold lines in the display cannon are not surprising. They are not manufactured to the same finish as operational cannon would be. The reason for a smooth finish is not just for appearances sake.

View attachment 523772
Many cannon were very elaborately decorated. Eventually, it was established that even minimal right angle embellishments were the source of fatigue cracks.

View attachment 523773
This is a bronze Ames model one 14 pound rifle.
Outwardly it is identical to an 1841 model six pound smoothbore.

View attachment 523774
The Ames model 2 rifle shares the elegant smooth lines of the 3" ordinance rifle.

View attachment 523775
Not so streamlined in shape, this Waird rifle shares the smooth finish.

View attachment 523776
Present day display cannon are often cast fiberglass. They can be so perfect in appearance that only a tap with a knuckle will tell what they are made of.

The examples of display only castings are of a rough finish. However, there is nothing wrong with that.

When the Constitution was converted to a barracks, all her original guns were recycled. Like the originals, the present armament was based on a 32 pound siege gun abandoned by the British.

Really interesting link to how a 40 MM saluting gun was inserted into the cast iron display cannon on the Constitution. It is an eye opener.

Link:

Firing a Salute - USS Constitution Museum

In the waning days of the USS Constitution‘s 1973-1975 restoration, Commanding Officer Tyrone G. Martin, investigated the possibility of retrofitting for saluting purposes two of. . .

ussconstitutionmuseum.org

I'd just mention that one way of figuring out if a 10 lb Parrott or a 3" Ordnance Rifle is a replica is a horizontal casting seam running along the tube.

 

[Rhea Cole]

I'd just mention that one way of figuring out if a 10 lb Parrott or a 3" Ordnance Rifle is a replica is a horizontal casting seam running along the tube.

The very best of modern cast aluminum display carriages & artillery pieces are, even at close range, indistinguishable from the real thing.

 

[Belfoured]

View attachment 523840

View attachment 523841

The very best of modern cast aluminum display carriages & artillery pieces are, even at close range, indistinguishable from the real thing.

Good point. As we know that's a comparatively recent development. There are a lot of replicas scattered about parks, etc that were made decades ago. The seam isn't the only way to id them but it's one.

 

[Rhea Cole]

Good point. As we know that's a comparatively recent development. There are a lot of replicas scattered about parks, etc that were made decades ago. The seam isn't the only way to id them but it's one.

Indeed, the bore of display cannon is only (+/-) 12" deep.

We really do know far too much about some obscure topics, ¿no?

 

[USS ALASKA]

Eventually, it was established that even minimal right angle embellishments were the source of fatigue cracks.

Hello de Havilland Comet...

USS ALASKA

 

[USS ALASKA]

Questions, sirs...at this point in industrial development, was welding technology able to handle something this large and thick and subjected to the tremendous operational pressures? Was the metal used at the time to construct cannon conducive to then current-day welding techniques?

Thanks for the help!
USS ALASKA

 

[Rhea Cole]

Indeed, the bore of display cannon is only (+/-) 12" deep.

Questions, sirs...at this point in industrial development, was welding technology able to handle something this large and thick and subjected to the tremendous operational pressures? Was the metal used at the time to construct cannon conducive to then current-day welding techniques?

Thanks for the help!
USS ALASKA

Today, welding involves electricity & some kind of a rod or wire. Nothing like existed in the 1860's.

The History of Welding | MillerWelds

Welding history dates as far back as the Bronze Age, but most welding developments took place in the 20th century. Learn more.

www.millerwelds.com

Pre 1900 welding was what we call a forge weld. Essentially, that involved placing two pieces of very hot ferrous metal & applying pressure. At the atomic level there is a migration that results in a seamless joint. It is the strongest weld there is.

Here the smith has positioned two pieces of steel onto the anvil. I was the striker poised to hit the mark.

As the hammer makes contact, flux & impurities are expelled from the joint. The metal has the consistency of modeling clay. The smith will return the joined metal to the fire, bring it up to color & that will relieve any stresses.

Forge Welding 101: Beginners Guide To Forge Welding

Learn how to forge weld and become a bladesmith with this 4-step guide that walks you through forge welding in a blacksmithing shop.

www.thecrucible.org

Welding cast iron, which is the subject of the thread, is problematic. My only personal experience has been brazing castings with a torch & bronze rod. I was taught that welding cast iron was, in practical terms, impossible.

How to Weld Cast Iron

Learn about the steps required for successful in-house welding of cast iron parts.

www.reliance-foundry.com

 

[Belfoured]

Indeed, the bore of display cannon is only (+/-) 12" deep.

We really do know far too much about some obscure topics, ¿no?

Some might say "useless" rather than "obscure" ....

 

[USS ALASKA]

Some might say "useless" rather than "obscure" ....

Esoteric...

Cheers,
USS ALASKA

 

[Belfoured]

Questions, sirs...at this point in industrial development, was welding technology able to handle something this large and thick and subjected to the tremendous operational pressures? Was the metal used at the time to construct cannon conducive to then current-day welding techniques?

Thanks for the help!
USS ALASKA

To follow up on Rhea's good explanation of forge welding, the process for what became the 3" Ordnance rifle used wrought iron rather than cast iron and utilized a rolling mill. The welding in John Griffen's patented process interprets as "practical welding". The several iron rods were welded together to form a center/core and several layers of wrought iron were then wrapped around this core on a lathe and were welded together. This is how he described the process in his 1855 patent:

"The pile for the gun, arranged and made as above described, is charged or placed in a heating-furnace, and the entire mass brought to a high welding-heat. The mass is then upset, as it is technically termed, by placing a heavy mass of iron against one end and striking a series of heavy blows against the other end. By this means all the edges of the spiral coils are brought firmly into contact and practically welded. The pile or faggot is then withdrawn. from the furnace, and is passed rapidly through a series of grooves formed between pairs of large rolls similar to those ordinarily used for rolling iron, thus welding the mass and reducing it to its proper size"

 

[Belfoured]

Esoteric...

Cheers,
USS ALASKA

Well done - covers all the options ..

 

[Rhea Cole]

The wrought iron used to make the 3" rifles made the forge welding of the gun barrel possible.

In simple terms ( that even I can understand ) wrought iron was made by reintroduction of slag to pure iron. This resulted in an amalgum rather than an alloy. The metal has a texture like wood grain or reinforced concrete.

The ductile iron can be shaped by forging. Because of the pure iron, it becomes "sticky" when heated to a bright honey color. It forge welds very easily. That is what made the 3" rifle manufacturing technique possible,

Wrought iron is no longer mass produced. I have only forged one piece with scrap from a fence. Forge welding modern steel can be finicky even for experienced smiths… very humbling fo learn. The wrought pieces I forged lived up to their reputation. I had to be careful to not let them touch on the fire.

In contrast, the crystalline structure of cast iron means that it can't be forged after it cools. It is not ductile even at high temperatures.

The wrought iron reinforce surrounding the cast iron breech of Parrott rifles is a synergy of the hard & ductile characteristics of iron.

What Is Wrought Iron? - Precise Iron Doors

Wrought iron may not be the most commonly used material, but it can beautify and enhance any home. Here’s what you need to know about this material.

preciseirondoors.com

Wrought Iron works | Wrought Iron Gates | Topp & Co

With the skills, knowledge and experience of our craftsmen, we restore heritage metalwork and create new ironwork to build on the legacy of decorative wrought ironwork in Britain and around the world.

www.toppandco.com

Modern wrought iron is high carbon steel. Traditional wrought iron is no longer commercially available except from this one source.

 

[Belfoured]

The wrought iron used to make the 3" rifles made the forge welding of the gun barrel possible.

In simple terms ( that even I can understand ) wrought iron was made by reintroduction of slag to pure iron. This resulted in an amalgum rather than an alloy. The metal has a texture like wood grain or reinforced concrete.

The ductile iron can be shaped by forging. Because of the pure iron, it becomes "sticky" when heated to a bright honey color. It forge welds very easily. That is what made the 3" rifle manufacturing technique possible,

Wrought iron is no longer mass produced. I have only forged one piece with scrap from a fence. Forge welding modern steel can be finicky even for experienced smiths… very humbling fo learn. The wrought pieces I forged lived up to their reputation. I had to be careful to not let them touch on the fire.

In contrast, the crystalline structure of cast iron means that it can't be forged after it cools. It is not ductile even at high temperatures.

The wrought iron reinforce surrounding the cast iron breech of Parrott rifles synergies the hard & ductile characteristics of iron.

What Is Wrought Iron? - Precise Iron Doors

Wrought iron may not be the most commonly used material, but it can beautify and enhance any home. Here’s what you need to know about this material.

preciseirondoors.com

Wrought Iron works | Wrought Iron Gates | Topp & Co

With the skills, knowledge and experience of our craftsmen, we restore heritage metalwork and create new ironwork to build on the legacy of decorative wrought ironwork in Britain and around the world.

www.toppandco.com

Modern wrought iron is high carbon steel. Traditional wrought iron is no longer commercially available except from this one source.

And, focusing on the 19th century, one major difference between wrought iron and cast iron was the significantly higher carbon content of cast iron. Another major difference was the cost, because cast iron was cheaper to manufacture. That gets us to Parrott's attempt to have the best of both worlds.

The 10 lb tube was cast iron. To "strengthen" it, Parrott put a distinctive wrought iron "wrap" around the breech. His process involved taking a 5 foot long, 4 square inch bar of iron, heating it, coiling it around a mandrel, and welding it by hammer to close the circle. The reinforcing band was re-heated, placed over the breech, and the tube was rotated horizontally on rollers while the wrap cooled in place. As a result the bar contracted around the breech evenly. The Parrott tube was markedly cheaper than the 3" Rifle. As we know, however, Parrott's larger calibers, starting with the 20 lb, had an unfortunate record of failure forward from the wrap.

 

[RetiredCanuck]

Today, welding involves electricity & some kind of a rod or wire. Nothing like existed in the 1860's.

The History of Welding | MillerWelds

Welding history dates as far back as the Bronze Age, but most welding developments took place in the 20th century. Learn more.

www.millerwelds.com

Pre 1900 welding was what we call a forge weld. Essentially, that involved placing two pieces of very hot ferrous metal & applying pressure. At the atomic level there is a migration that results in a seamless joint. It is the strongest weld there is.

View attachment 523863
Here the smith has positioned two pieces of steel onto the anvil. I was the striker poised to hit the mark.

View attachment 523862
As the hammer makes contact, flux & impurities are expelled from the joint. The metal has the consistency of modeling clay. The smith will return the joined metal to the fire, bring it up to color & that will relieve any stresses.

Forge Welding 101: Beginners Guide To Forge Welding

Learn how to forge weld and become a bladesmith with this 4-step guide that walks you through forge welding in a blacksmithing shop.

www.thecrucible.org

Welding cast iron, which is the subject of the thread, is problematic. My only personal experience has been brazing castings with a torch & bronze rod. I was taught that welding cast iron was, in practical terms, impossible.

How to Weld Cast Iron

Learn about the steps required for successful in-house welding of cast iron parts.

www.reliance-foundry.com

Welding cast iron is not impossible. There are specialty companies that do this on a regular basis. One of the biggest applications is antique and irreplaceable aircraft and automotive engine blocks that have corroded or cracked.
But these welds do not behave like traditional steel "melt and fill" bead. They will never have the mechanical strength of the parent metal and are basically leak/pressure resistant only.
The technique requires special pre and post weld heating or the weld area will fracture.
But as mentioned above the techniques and equipment did not exist in the 1860s. Even today I would not trust a weld in a cast iron artillery barrel.

 

[Rhea Cole]

Welding cast iron is not impossible. There are specialty companies that do this on a regular basis. One of the biggest applications is antique and irreplaceable aircraft and automotive engine blocks that have corroded or cracked.
But these welds do not behave like traditional steel "melt and fill" bead. They will never have the mechanical strength of the parent metal and are basically leak/pressure resistant only.
The technique requires special pre and post weld heating or the weld area will fracture.
But as mentioned above the techniques and equipment did not exist in the 1860s. Even today I would not trust a weld in a cast iron artillery barrel.

It would be useful to read the article I posted a reference to about welding cast iron.

Might as well point out, then or now nobody was welding the haves of a cast iron 32 pound naval cannon. It makes no sense on many levels.

Now days, 3-D printing a an outward shell & fitting a steel sleeve would work very well. The Trafalgar Gun Company in England has fiberglass 32 pounders. Cast from mold pulled from an actual Napoleonic era gun, you have to get very close to see that it is a copy. They have a central 40 MM center sleeve surrounded by eight small ones. They use a gas system, so the 1812 Overture, for example, can be timed exactly with only a few guns.

Don't know how many traumatic amputations have resulted from black powder attempts to maintain the tempo.

 

[RetiredCanuck]

It would be useful to read the article I posted a reference to about welding cast iron.

Might as well point out, then or now nobody was welding the haves of a cast iron 32 pound naval cannon. It makes no sense on many levels.

Now days, 3-D printing a an outward shell & fitting a steel sleeve would work very well. The Trafalgar Gun Company in England has fiberglass 32 pounders. Cast from mold pulled from an actual Napoleonic era gun, you have to get very close to see that it is a copy. They have a central 40 MM center sleeve surrounded by eight small ones. They use a gas system, so the 1812 Overture, for example, can be timed exactly with only a few guns.

Don't know how many traumatic amputations have resulted from black powder attempts to maintain the tempo.

I did scan through it. Very thorough. But was actually replying to the quote below from the same post that said:

"I was taught that welding cast iron was, in practical terms, impossible."

 

[Belfoured]

It would be useful to read the article I posted a reference to about welding cast iron.

Might as well point out, then or now nobody was welding the haves of a cast iron 32 pound naval cannon. It makes no sense on many levels.

Now days, 3-D printing a an outward shell & fitting a steel sleeve would work very well. The Trafalgar Gun Company in England has fiberglass 32 pounders. Cast from mold pulled from an actual Napoleonic era gun, you have to get very close to see that it is a copy. They have a central 40 MM center sleeve surrounded by eight small ones. They use a gas system, so the 1812 Overture, for example, can be timed exactly with only a few guns.

Don't know how many traumatic amputations have resulted from black powder attempts to maintain the tempo.

An example of 19th century welding problems was the catastrophic explosion in 1844 of the 12" smoothbore gun "The Peacemaker" on board the USS Princeton. That gun and its twin were both made of wrought iron, but the Peacemaker was manufactured in the US and the other was founded in England. The US gun was made by welding the component iron bars while the gun made in England had the bars shrunk on. The obvious difference is that shrink wrapping, unlike welding, would prevent any cracks from expanding. Another problem was that the US-made gun was heated to near the melting point for a lengthy period of time resulting in larger grains and areas of weakness between the grains. This could have been offset by working the metal with a hammer but the hammer used by the founder was too small for the task.

Suffice to say that some lessons were learned by the time Griffen developed his wrought iron process for what became the 3" Ordnance Rifle.