jma1009
Elder Statesman
Posts: 5,896
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Post by jma1009 on Oct 24, 2021 20:58:07 GMT
I think the injectors will be difficult to reverse engineer to a working format. Does anyone therefore have any recommendations for a suitable commercial alternative? Presumably No 2 size. The inlet pipes are 1/8” and the outlet 5/32” some of the fittings have incredibly fine threads, probably What do you mean, Tim, about "reverse engineer" in respect of the injectors? Happy to help out if you send me a PM. Cheers, Julian
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Oct 24, 2021 23:01:49 GMT
“I wish I could find out more about the builder of this engine, it has some very neat features.” Not too sure if its the same chap but and Ian Jaycocks entered the 2002 IMLEC at Leeds with a beautiful 2-8-0 Buffalo, there a picture of him driving the loco. ME 2003, June 27,Vol 190,no.4198. Thanks John. I have sent off for a copy. Interestingly, the boiler lagging is Kelloggs cornflake packets with the latest date of 2003 on the inside. Another bag containing two working scale blowdown valves is dated 2013 (there is also a big valve at the front of the firebox). Thanks Julian, I will be in touch. I got the snifter valve working this evening: it didn’t have a valve in it but I found one in the odds & sods bag and adapted the seat for it. It should have another on the other side, but I presume that could be a dummy. The smokebox door periphery is not quite right - it’s proportions are out, but I think that can be easily modified. Tim
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johnd
Part of the e-furniture
Posts: 281
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Post by johnd on Oct 25, 2021 9:30:19 GMT
Tim, As a postscript to my earlier post, about Ian’s buffalo, i had a feeling that I had seen this loco before. Typed buffalo into SRS archive and there is was, confirmation that the photo in ME is of Ian.
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Oct 25, 2021 16:58:41 GMT
Thanks again, John. That has struck a rich seam for info on the three other engines that have gone through SRS. Having seen these, I am much more confident about the KA and can see some common design features such as the flanged steam turret. I’ve been working on the front end of Sir Percivale today. The KAs were handsome engines when first built, especially the NBL locos: these had smooth lines and very few rivets at the front end. Once smoke deflectors started to be fitted so did hundreds of rivets! I’m not sure whether Ian intended to do further work on the KA smokebox, but it wasn’t quite right - looking a bit like a Hughes L&Y engine. A morning’s work on the lathe has made some modifications. It’s quite tempting to make the rings more prominent, similar to the MR Deeley doors, but these Maunsell smoke box fronts are rather more subtle. I suspect that the very small inner ring should be part of the door, rather than the front but, as they say, I think it’s good enough for government work… Tim
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mbrown
Elder Statesman
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Post by mbrown on Oct 25, 2021 17:14:23 GMT
I don't think the inner ring is part of the door. There is a picture in S C Townroe's book, "The Arthurs, Nelsons and Schools of the Southern", showing a Schools with the smokebox door open and what you refer to as the inner ring is clearly attached to the smokebox front plate. It is not absolutely clear but it looks as if it may have held a resilient ring for the edge of the door to pull up against - maybe some sort of graphited yarn in a bigger scale than we use! There is clearly no ring as such on the edge of the door.
Malcolm
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 3, 2021 18:45:29 GMT
Sir Sagramore ran on air today for the first time (with me) today. Everything as it should be: I’m very pleased - it is a credit to the skill of Ian Jaycroft, the builder. youtu.be/pLiQy61XpZYTim
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 6, 2021 22:10:12 GMT
Quite a few of the fittings and unions on Sir Percivale have 60 TPI threads at quite big diameters: < 6mm. Does anyone know where taps and dies can be sourced for these as it would be good to continue with these standards if components require re-making. They might be an ISO fine thread II (metric) Din 13-3, but that has a 0.5mm pitch (equivalent 50.8 TPI) Any suggestions?
Thanks Tim
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Post by John Baguley on Dec 7, 2021 12:10:31 GMT
I believe that there is a 60 TPI ME thread but probably as rare as hen's teeth now so it may be difficult/next to impossible to source taps and dies. I've never seen any even secondhand. I do have some 60 TPI Whitworth taps and dies but they only go up to 5/32" or 3/16" diameter (can't remember without looking).
You may have to resort to screwcutting your threads
John
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Post by ettingtonliam on Dec 7, 2021 12:38:46 GMT
I've got a Kennions catalogue from 1938, which covers 60TPI taps and dies, from 1/16" up to 3/8", but they claim to be the only firm making these fine threads.
Unless you get really lucky on ebay, I don't think you are going to have much success in sourcing 60tpi taps and dies. Certainly Tracy Tools, who have some really odd sizes don't seem to stock them. Apart from 1/16" Whitworth which is 60 tpi and does seem to be available, I haven't spotted anything else.
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Post by cplmickey on Dec 9, 2021 9:00:48 GMT
Tracy Tools do say though that "We also manufacture special size taps, dies, dienuts and reamers. One off Specials can be manfactured in as little as 7 days." so it might be worth trying them if you only need an odd one or two. Ian
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Post by ettingtonliam on Dec 9, 2021 9:07:41 GMT
They do, but I suspect you might have to mortgage your grandmother to pay for them.
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Post by cplmickey on Dec 10, 2021 20:44:59 GMT
Some time ago I had a left hand thread set of taps from them that wasn't listed in the catalogue and I don't remember them being maga-expensive. Something tells me they were 3 x the carbon steel RH taps but I could be wrong, it was ages ago.
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 12, 2021 23:41:17 GMT
Granddaughters have been introduced to Sir Percivale. Tim
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 14, 2021 18:35:56 GMT
As mentioned in the tail stock die holder thread, I have now sourced some 60 TPI taps (2nd & 3rd) and dies for 3/16” diameter and 5/32” from Tracey Tools. I phoned them yesterday lunchtime and they arrived today, just after lunch. I honestly don’t think you could better that service, especially as I don’t think they were a stock item. Total cost for six items £61.20
On a different note, any recommendations for the best source of an appropriately-sized pressure gauge?
Tim
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 23, 2021 16:21:53 GMT
Christmas came early for me, with a successful boiler shell test for Sir Percivale. It wasn’t quite straightforward as there was one internal stay that was weeping under 2x pressure and, needless to say, access was a bit tricky being slightly behind the convexity of the firebox. The original silver solder had inadequately penetrated on the far side of the stay. A couple of hours trying to swage it using a specially made tool, simply rounded off the top. The area was cleaned up using a brand-new, but 50 year-old dental handpiece powered by my equally ancient dental engine, complete with a nasty large inverted cone bur. A front-surfaced mirror, headlight and loupes aided vision. The whole boiler was then gently heated up on a hearth of firebricks and the gas flame concentrated on the outside of the offending stay. Once up to temperature the solder flashed nicely into the joint with plenty of flux, following the heat. I have learnt a lot from this little exercise, with lots of useful advice from my friends in the North London Society of Model Engineers. Tim
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cfmrc
Seasoned Member
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Post by cfmrc on Dec 27, 2021 16:55:09 GMT
I have started to work on the rear end of Sir Sagramore (so to speak) and dismantled the RHS injector. This is more complete than the LHS, including the steam cone. As for the LHS, there is a delivery cone, seen here with a view from the top. There is clearly the combining cone missing, whilst the relative positions of the other cones can be seen in this ventral view. The steam cone finishes ahead of the water inlet opening (there is a fine spacing washer next to the mating surface with the injector body)whilst the bell opening of the delivery cone can be seen ahead of the overflow. It would be good to get one of the Ian Jaycroft injectors working. It will need the combining cone reverse engineering and a ball and plug for the valve on top. Questions arising, are: Any idea what overall length / taper proportions the combining cone should have? How would the combining cone be stabilised in the middle of the injector body? What size ball for the valve: the hole is 3/32” diameter. How much lift? Maybe I’m expecting a bit much of this: I will definitely use a small Chiverton injector on the other side, when I can source one. Tim
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 28, 2021 19:52:09 GMT
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Post by mr swarf on Dec 28, 2021 20:37:27 GMT
Hi Tim, can't help with the cones but generally a 1/8" ball is used on a 3/32" seat with a lift of 1/32. Paul
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jma1009
Elder Statesman
Posts: 5,896
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Post by jma1009 on Dec 28, 2021 23:18:49 GMT
Hi Tim,
You had a PM on the subject of injectors on 27th October that you did not reply to.
Cheers, Julian
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cfmrc
Seasoned Member
Posts: 107
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Post by cfmrc on Dec 29, 2021 7:58:52 GMT
Sorry Julian, I missed that. I’ll give you a call if I may.
Tim
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