1 3/4" id cylinder rod

[191701]

Found some 1 3/4" id 2 1/2" od chrome plated cylinder rod.   Seamless. Just wondering what you guys would do with it, if anything.  I have about 4'.  Thanks

[dan610324]

gb mortar or howie

[Terry C.]

Yes, something with a machined breech plug that incorporates a powder chamber.

GB howitzer sounds like a good idea. You wouldn't want it too long, about eight calibers of bore, plus the chamber.

4' should make two.

[Cat Whisperer]

Being chromed it's likely VERY smooth.

Being 1.75" ID that's a bit big for golf-balls, but if patched loosely (thin patch) that has potential.  
I would not use a patch in just any cannon/mortar - ONLY if it is right-much smooth and consistant in diameter.

With 4' of it you have a number of options.  You could even make a mortar BATTERY.

[Double D]

Patched, .035 thickness? 

[191701]

Its chrome on the outside not the inside. Would there be anything wrong with making it long?  Maybe a powder chamber plug and a sleeve over the outside to cover the chamber area for extra strength.   

[Double D]

I think we had a discussion on those cylinders a few weeks back and decide they were DOM welded seam.  I'm not sure if we figured out the type of steel.  If I remember right the consensus on these cylinder was to pass...mainly because they are made of unknownium.

[191701]

The id measures +- .001"   So if there is a weld seam there will be micro pits in the seam which will corrode over time.  Is this the main reason not to use it or is it strength also.  Thanks

[Cat Whisperer]

The id measures +- .001"   So if there is a weld seam there will be micro pits in the seam which will corrode over time.  Is this the main reason not to use it or is it strength also.  Thanks

I count two reasons.  One is the porosity. Two is the material.  It likely was designed for the strength needed as part of something hydraulic.  The 'strength' is likely to be there, but it also is likely to be much harder (that adds to the strength) than what one would want for a cannon.  A cannon must be able with withstand cracking - hence the mild steels (1018 and others) work so well.  The harder the material is the stronger (generally) and the greater the likelyhood of cracking under the repeated firings.

[armorer77]

While , I haven't worked with hydraulic tube rams , my experience with the solid rods has been nothing but good . Armorer77

[Terry C.]

Here are a few thoughts based on my experience building and maintaining hydraulic equipment.

Is it in fact a hollow ram and not a barrel? This makes a big difference.

Seamed tubing is for barrels, rams are generally made solid because of the steels used. Hollow rams are a tradeoff between strength and weight. A hollow ram would almost certainly not be made of a seamed tubing, or a brittle alloy, the result could be disastrous.

Rams are generally not made from overly hard alloys, they don't well work in these applications for much the same reasons given for why they are less suitable for cannons. Rams are generally made of tough steels that will 'give' under pressure rather than break. Rams are subjected to extreme stress and physical abuse. A ram that bends instead of breaking can be the difference between life and death for a crewman in harm's way.

Rams need to be weldable. A ram has to have some sort of attachment point, or it's pretty much uselss. And these wear out or get damaged and have to be replaced. Usually this is done in adverse conditions with the most basic of setups. It has to take the weld well and be strong and safe enough to resume operation.


Just my thoughts. Most of the equipment I deal with is large and dangerous, so I am a bit opinionated.

YMMV

[Cat Whisperer]

Good words of experience.   

[191701]

So if I decide to make a golf ball howie out of it.  What are my options?  Plug the end with a pressed and welded plug?  Weld on the end  several inches away from chamber.  threaded plug? Sleeve the outside chamber area also?  Weld trunions to the outside sleeve?  Just throwing some ideas out. Thanks again.

[dan610324]

heat shrink and weld

NOT PRESS AND WELD

[rludwig]

I'm still sort of a newbie. Still working on my first cannon. I don't quite understand the difference between press fit and shrink fit. It seems to me that both should end up with the sleeve slightly compressing the plug.

[dan610324]

a correctly made shrink fit compress the plug harder and is stronger

[GGaskill]

The difference between press fit and shrink fit is this:  a press fit forces an undersize sleeve over an oversize shaft while a shrink fit relies on heating the sleeve to expand it larger than the (sometimes cooled) shaft so it simply slides on without any resistance.  Now it has to be done quickly as once the sleeve contacts the shaft it starts cooling off and shrinking and quickly the project can become a force fit.  But the intent is that the hole in the sleeve is larger than the shaft for the time it takes to position it on the shaft.  That is why the difference in diameters is so critical.

[191701]

I'm back and thinking about this again. What about a threaded breach plug?   Maybe a 1 7/8" 16 threaded plug. 3-4 inches long.  Maybe a 5/8" powder chamber. The plug could be removed and cleaned. Could I still get some distance out of it?

[KABAR2]

Here are a few thoughts based on my experience building and maintaining hydraulic equipment.

Is it in fact a hollow ram and not a barrel? This makes a big difference.

Seamed tubing is for barrels, rams are generally made solid because of the steels used. Hollow rams are a tradeoff between strength and weight. A hollow ram would almost certainly not be made of a seamed tubing, or a brittle alloy, the result could be disastrous.

Rams are generally not made from overly hard alloys, they don't well work in these applications for much the same reasons given for why they are less suitable for cannons. Rams are generally made of tough steels that will 'give' under pressure rather than break. Rams are subjected to extreme stress and physical abuse. A ram that bends instead of breaking can be the difference between life and death for a crewman in harm's way.

Rams need to be weldable. A ram has to have some sort of attachment point, or it's pretty much uselss. And these wear out or get damaged and have to be replaced. Usually this is done in adverse conditions with the most basic of setups. It has to take the weld well and be strong and safe enough to resume operation.


Just my thoughts. Most of the equipment I deal with is large and dangerous, so I am a bit opinionated.

YMMV

I have to agree with Terry,

I have a sick 14 year old 30 ton Die Press,  the platen is held onto the ram by being bolted to a collar, the collar is held to the ram with 4 Allen bolts up inside the tube, the Allen Bolts are harder then the ram, evidence of this is the bolts wore the threads out in the ram and the bolts would fall out even with locktite causing the platen and collar to drop to the table unexpectedly (read dangerous) as the problem was becoming chronic I was forced to take the ram out for repair it seems the last person who put it back together when I was off neglected to tell me two of the Allen bolts sheared off. after removal it was drilled and tapped for larger bolts & to keep them from backing out I drilled holes through the heads of the bolts and wired them together to keep them from turning..... mind you this is done inside a pipe (collar) about 6 to 7 inches ID  10" up inside it and blind....... SO FAR SO GOOD!....