As can be seen, a 'light maintenance' task can sometimes give the impression of the start of a full overhaul! The original water pumps were removed from the engine during that week. Following closer inspection it was decided to first attempt to sleeve the internals with bronze bushes which would, in effect, take up the slack. The rams are made of a much stronger material than the pumps themselves and thus have lasted rather well considering. Using a hefty milling machine, we managed to bore one of the old pumps square and sleeve it successfully. Unfortunately its sister pump was not so lucky and the cutter broke through the wall whilst trying to bring it back parallel on the bore. The wear was just too great to bore out of that one: the material had lost all strength. With the prospect of having to make a new pump, common sense said to make two. New castings were duly ordered from Reeves and during the first week of July they were being machined into pumps...
The castings come with the basic shape already clear to see but with much machining still to do. Once you have a centralised stub machined to work from, the castings can be held in the lathe central on a 3-jaw and machined accordingly. Here they are almost complete, with one pump still keeping its guide stub at this point...Here are the completed pumps with rams fitted, awaiting new brass gland nuts...
The pumps did take a bit of extra fettling here and there and progress was slowed up by the various bits & bobs going on elsewhere in my life during these weeks. My main slow up was my job change which took a considerable amount of time to organise and get used to. Tonight saw a long overdue visit to the workshop to continue with the tank engine. The die we had used to achieve the 9/16" UNF thread was not entirely precise and so I had got hold of a brand new die and ran it down the thread on both pumps. The resistance encountered with the die showed just how much material the old counterpart had left on! One of the pumps is spotted below whilst its sister is receiving attention in the vice...
A trial fit has been made of the pumps (with access aided via the removal of the RH water tank) and, as I write, the pumps are now at the workshop of 'Eddie the Late' in order to have a slight edge turned off them. The thread doesn't go quite far enough to the edge of the circumference of the barrel and so they don't screw into the frame stretcher quite as far as they should. Ed is kindly turning a little off for me. Once they're back, the tank's bottom end can be put back together before the boiler cladding receives attention prior to rebuild. Meanwhile, on the Eastern side of things with "Maisie"...
The Great Northern Atlantic has, this time, required no maintenance work or repairs. She has had her tubes swept, grate & ashpan emptied and has had her paintwork polished and brass shined up but other than that she hasn't changed. She did very, very well during her last outing and is now running well. The engine was planned to go out tonight to the CMES 'Third Wednesday' steam up but, allas, rain stopped play and there was no way that the just polished Apple Green livery was heading out into a rain storm!...
So folks, that's it for now. I am not entirely sure when either of the engines will run again but I'm sure we'll have a few more outings before the end of the year. "Achilles" should be ready again in the next few weeks/months: no promises! There is always something to do: not enough hours in the day. Best Regards, Sam...
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