This little bronze worm wheel, part of a 40 year old engine, failed last week.
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The makers were able to supply a replacement by next-day delivery. When the engine was new in the 1960s, they were listed in the manual at £3 10s 2d. How much today??
Allow not just for inflation, but for the company existing now mainly as a spares supplier, & they quite likely only turn over single figure numbers per annum of this sort of thing.
Well when I bought a very similar one for my Pedrazoli Mecbrown cold cut off saw it cost £174 plus carriage plus the VAT . I was amazed that they still had them as the saw is late 1960's
The RPI was 12.6 in 1960 and is 206 now, a 16 fold increase. Allowing just for inflation it should be about £60. Actually on cnc machines nowadays you could knock those out for a fraction of that and maybe the company hasn't allowed for only selling one a year. So the question is do I guess silly expensive or silly cheap? I'll say £40.
£240 ++ Or so I'm told, luckily I didn't have to fund it, even temporarily.
This is the engine:-
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Kelvin T8
This is a later version:-
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The gear is on a cross-shaft which drives two ram (reciprocating) water pumps, one for raw water and one clutched bilge pump. A nut had come adrift in one of the pumps and jammed under the end of the piston rod, causing the stripped gear & a bent shaft. All back together & up and running as of this evening.
I expect a new gear could have been made, even as a one-off, for less than that subject to finding someone with the right equipment & right size hob to do it, but not on a next-day delivery basis, plus there's always an element of doubt when working from a (knackered) sample rather than from a drawing.
Now if you had only asked me first ---------------- there you go another lost sale and mine were only £239.99 each ;-) Go on then what is the T8 driving? Just for interest, there is a T4 going into an old Tug at R.W. Davies at Saul soon. Replacing a big Mann Diesel.IIRC. BTW I am looking for an HR3 or something similar for a colleague currently building a 70 ft NB. If you know of anything please let me know.
-- Richard
Nb "Pound Eater" Parkend G+S "Governments are like Nappies, they should be changed often." (For the same reason)
Another thought, I have a Dorman 2DL looking for a home. This would make a very nice engine for a large NB, 30 bhp @ 1000 rpm, but there would be a fair bit of work to do in marinising etc. Open to offers, it's a bit in the way at present!
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