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Discussion Starter · #1 ·
Afternoon all,

I thought I would post some pictures of a restoration of an 18 Pounder field I completed not too long ago. It is a representative of early production in 1905. Although there is an artillery section in GB, I think this is more at home in the Commonwealth weapons.

I am looking for some more 18 Pounder bits and pieces for the next project, which will be a late war type. I am hoping this post may be interesting to y'all and turn up some new leads for some missing parts. Amongst other things, I am looking for wheels, gun carriage sections and an 18 Pounder gun rule.


The original project started on a farm ...swords turned to ploughshares in 1946, and barrels turned to fencing strainer posts. Unfortunately, most of the bronze parts had been stripped off for scrap.



For the first gun, there was about 70% of the parts needed to get to something like this:



However, the next gun will be a bit more challenging as it is starting from a parts base of maybe 40%.

As I get time over the next few weeks, I'll post some more photos that show the progress of the first restoration.

ATB, D.
 

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Discussion Starter · #3 ·
After stripping the trail down, I had the components blasted and primed. The trail spade was reconstructed and is the earliest type. There are about four variations of the spade between 1905 and final production in 1918.


It took quite a while to get this far, but when the trail starts coming together, there is a good feeling of progress.


ATB, D.
 

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Discussion Starter · #10 ·
Can't be all that many left, given that many of the survivors were given pneumatic wheels and a new carriage and converted to 18/25 pndrs
Indeed Mk VII, there are not many left. This is one of the Mk.I / Mk.II variants that did most of the slog in WWI. They made about 12,000 of these before production ended in 1918.

The next 18 Pounder to see service was the Mk.IV, which looks more like a standard field gun as used by most other countries. From what I can make out, there were about 4000-5000 of these guns made. The Mk,IV barrels are the ones that were converted to 25 Pounder. Only a small number of these guns were not converted to rubber tyres by 1940.

After 1945, the Commonwealth armies could not get rid of these guns quick enough. Many were sold to farmers for a couple of Pounds and you know the rest. Hopefully someone still has some parts out there....
 

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Discussion Starter · #11 ·
The next major obstacle in the restoration was getting the "cradle". This is the part that holds the barrel, recoil system and the trunnions together. In an 18 Pounder, it is a large cast framework made of 92kg of manganese bronze. Of course, these were hacked off the guns by the farmers, who could get more money for the scrap bronze than they paid for the whole guns.

I had to get a copy of the cradle drawings (many thanks Paul) and make casting patterns. This took literally years



But when the patterns were made, the casting process was swift,

. The new casting on the scales at the foundry.


but machining it took a while. There were lots on unique and strange machining operations to get your head around, but got there eventually.
 

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This is obviously a labour of love, and you are doing a wonderful restoration--please keep the photos coming!!!
How does liquid bronze, probably at ~700 C, not burn its way through the (poorly-heat conducting) wooden moulds?

Regards,
JMB
 

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Without stealing the glory from the OP, the wood mould isn’t a mould it’s a positive form or pattern, i.e. a true representation of the finished item. The wood is used to make a sand mould in 2 or more parts, this is the negative. The wood is now removed and can be reused to make another sand mould. The sand mould is put back together and the molten liquid is poured in from the top until it is full. It’s then left to cool before the sand mould is Brocken away to reveal the casting ready for machining. There’s more to it obviously, things like contraction of the casting so making the pattern a % bigger to counteract the contraction etc. It’s a proper science and I take my hat of to the pattern maker. Dare I say it’s a dyeing trade.
 

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Discussion Starter · #17 ·
Without stealing the glory from the OP, the wood mould isn’t a mould it’s a positive form or pattern, i.e. a true representation of the finished item. The wood is used to make a sand mould in 2 or more parts, this is the negative. The wood is now removed and can be reused to make another sand mould. The sand mould is put back together and the molten liquid is poured in from the top until it is full. It’s then left to cool before the sand mould is Brocken away to reveal the casting ready for machining. There’s more to it obviously, things like contraction of the casting so making the pattern a % bigger to counteract the contraction etc. It’s a proper science and I take my hat of to the pattern maker. Dare I say it’s a dyeing trade.
Thanks brit plumber - couldn't have explained it better myself. With manganese bronze, the shrinkage is about 1.5 -2%, so the pattern is 102% the size of the original. This is quite significant over a casting of this length. Sometimes you can get away with utilising an original part for a casting pattern, but the pattern maker still has to glue bits of shaped wood onto the ends, etc to bulk it out to the 102% size. However, this can introduce other inaccuracies on complicated shaped parts. As this cradle was so complex, it was not possible to use an original (even if one was available) as you cannot use it to form the internal voids. These internal voids are produced using "core boxes", which make the sand shapes that are mounted inside the external sand mould before pouring the molten metal. ATB, D
 

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Discussion Starter · #19 ·
This is very enjoyable.

What nation is this restoration occurring in? I am assuming the UK.

What would farmers do with a 18 Pounder gun? Convert it to a plow?
Hi Fritz, glad you find this interesting. The typical use for these guns was to use the barrels as "strainer posts" in wire fencing as they were nice and solid, and you could really tension up the wire without it bending. The gun trails were used as tractor trailers mainly. The elevation gear was used to jack up a tilt tray of some sort using a chain drive - maybe a fertiliser or dirt tipper. You can see the chain sprocket on the lower elevation mechanism with the sprocket,

ATB. D
 
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