Author Topic: Can a cast barrel be lathe turned to clean it up? (Read 771 times)

threepdr · « **on:** January 19, 2006, 09:57:56 AM »

I'm considering buying on of these repro Kings Howitzer barrels. Can it be put on a lathe and turned to clean it up and give more definition to the reinforces, base ring, muzzle ring and other details? The casting lacks alot of the detail of the original. The tube is only about 17 inches long and weighs about 60 lbs.

Powder keg · « **Reply #1 on:** January 19, 2006, 12:53:57 PM »

Hello, The only problem area is around the trunnion area. Other than that not a problem. I could do it for you. PM me if your interested.

Wes

GGaskill · « **Reply #2 on:** January 21, 2006, 10:18:11 AM »

One thing to remember about lathe turning a casting is that you have to take metal off all the way around to get rid of a small flaw. In some cases, it is better to bondo a casting flaw rather than trying to machine it off.

In the case of refining the detail, machining is certainly an appropriate process.

kappullen · « **Reply #3 on:** January 22, 2006, 04:16:06 PM »

The trunnion area isn't a real problem anyway.

I picked up a Gorton Engraving machine with the capabilities
of doing cylindrical jobs, like cups etc.

I may, with some practice, be able to do some of that work, but those snakes are still over my head.

A little modeling clay on the pattern, perhaps, may do the trick.

Kap

Double D · « **Reply #4 on:** January 23, 2006, 12:13:54 PM »

Following this thread and the other on the Daniel King Howitzer, I wonder if they were built any where near the precison we giving it to today.

My guess is that if you were to measure each and every one of them if they still exist, you would find that the only precison measurement is that of the bore.

Have you ever noticed that all the new modern guns and weapons have these precise arcs and angle and sharp square corner, all computer generated clones.

There somethng about the old guns with their soft flowing but not perfect lines...

kappullen · « **Reply #5 on:** January 23, 2006, 02:40:40 PM »

If you look close at some of the Columbiads at Fort McHenry, you can see that the lathe operator would "bump" the tool every couple of revolutions in to follow the profile of the casting.

These guns were produced under the stress of wartime.

I suspect the King Howitzer was turned where possible and hand polished by the crews of a peacetime army at the unaccesable areas.

Cannons Ltd Catalog at one time claimed to hand polish between the trunnions, but one of the other suppliers (Steen Cannon), showed a barrel on a fourth axis machining center skimming that area with a mill.

Your howitzer may be straight and true, or could have quite a twist to it.
In the latter case a lot of material may need to be "skimmed".

My swivel gun pattern warped and I had this problem.

Kap