jma1009
Elder Statesman
Posts: 5,901
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Post by jma1009 on Aug 23, 2013 21:34:47 GMT
hi pete, just be warned when using the dremel that silver solder is much harder than brass or copper - quite easy to 'slip' and remove brass instead of the silver solder accumulations! round headed dental burrs about 1/8th diameter work very well on their sides but not the ends. cheers, julian
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Post by Deleted on Aug 29, 2013 19:23:29 GMT
evening guys... I have a little video to share of 4470 running at the club track today, here she is driven by young Martin who I asked to try her out as I was still having a few issues. This video was taken after Martin had done a lap without having to stop (where I them jumped on to see how he fired her) that was a first and proves to me that I need a lot more practise. However it's not all me as on the lap shown here we did have to stop on the steepest gradient on the circuit and you can hear me chatting to Martin for his views, he's seen as a bit of a wiz kid by other members hence why I asked him to try her out. So symptoms: Loco has no problems with raising steam, takes between 20-25 mins and when she does drop to low to run it doesn't take long to get her back to steaming again. She was loosing steam and also wasn't getting enough oil to her outer cylinders. Steam leak turned out to be a leak on the left hand cylinder where the steam pipe enters the steam chest.. an easy fix. Oil issue was a strange one until the problem was found, at first it looked like she hadn't used any oil at all, in fact she had gained some. took the centre cylinder oil pipe off and ran on air... oil was being pumped as it should. Whilst doing this it was observed that air bubbles where coming up into the lubricator tank so I knew I had a possible clack issue. First we disconnected the steam pipes from the lubricator clack to see if oil was being pumped around. After some minutes of running on air it was obvious that no oil was getting past the clack, took the clack off to investigate and discovered that there was two balls in the clack?? It's a commercial item and although I'm sure it's been checked before I'm also pretty sure that i don't recall it having two balls, anyway the extra ball was removed, a new spring was put in and cut until the clack worked both ways. Everything was put back together again and run on air, after a few minutes the oil began to show at the clack which we had left off to check for flow. The clack was then refitted and again run on air to check that oil could get pass the ball, this was a success, we finished reassembling the remaining parts and ran on air for about 10 minutes, this time it was clear that oil was getting to the outside cylinders, so it seems that the outside cylinders had been running dry... not very good for achieving a successful run. whistle was still a problem that I'll address next, also it was noted that the blower rings were partly obscuring the aft blast nozzle so again a little work needed here, I'm thinking of remaking the blast nozzle caps to the correct size and making the outer ring so the the blower rings clip in place and thus can't move as all they are is a small copper tube that has two coils around the nozzles, they are very easy to knock out of place or perhaps even move themselves when the blower is used, I plan to cure that. Anyway, here's the link to the video, www.dropbox.com/sc/wyblphv7wcdxuke/vHIYY8SVjb A special thanks to Julian who kindly sent me some good Welsh steam coal which certainly did help, many thanks to you sir... oh and not too many laughs at the video guys... I'm still learning after all... Pete
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Post by digger on Aug 29, 2013 20:21:19 GMT
Pete
That was an excellent video, you are almost there now, effective lubrication to the cylinders is essential if economy of steam is to be obtained as the oil provides a seal for the valves and pistons, this has been one of the problems with my locomotive. Do you have a workshop compresser capable of pressurising to boiler to blowing off point? I have, and I use a stethoscope to listen for, and locate the smallest of leaks, it's amazing how much pressure can be lost via small leaks. Effective aignment of the blower ring's / jets can be checked using smoke pellets used by gas fitters to test flues, pop a lit pellet in the fire box then open the blower valve,it works! I feel sure that next time out will be a complete success, the locomotive is looking fine and will soon go as well as it looks.
Digger
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pault
Elder Statesman
Posts: 1,497
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Post by pault on Aug 30, 2013 7:44:51 GMT
Hi Pete I would echo what Digger said about oil being needed for sealing, this is very true with slide valves. My experience with some of our slide valve locos is that lubricator failure can result in reduced power, the loco sounding off beat and blows up the chimney. Restoring correct lubrication is like a miracle cure, as the oil gets round the power returns the beats even out and the blows stop. Part of your steaming problem could just be excessive use of steam due to leaking slide valve due to the lack of oil I would be very encouraged by that run, and now you have sorted the lubrication problem I would just go straight back to the track and have another go. I would also increase the load you are pulling to whatever would be considered a normal load for the loco. Quite a few of our locos need a bit of blower when running with light loads as the blast is not quite enough on its own. With some of them the bigger the load the better they steam. Regards Paul
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Post by Deleted on Aug 30, 2013 16:19:36 GMT
Thanks Digger /Paul yes Digger I do have a compressor capable of pressurising the boiler until the valves blow, I have used this a number of times to check for leaks although admittedly only using my ear. The leak that developed around the steam chest wasn't there before as I had checked... I'll reseal the screw with some sealant and try again. I haven't tried the smoke pellet trick yet, I'll ask my son to try and get some pellets from his plumber friends and give it a go. Thanks Paul, I was very encouraged by the run and even more so when I found the problem with the oil clack, it mayu be a week or two before I can get back, depends if one of my son's is free,, I am beginning to ask myself perhaps a smaller loco would have suited me more.... Regarding how the loco sounded I did notice once the oil began pumping properly that the note from the exhaust changed even though it was only running on air and also that she picked up speed at the same regulator/reverser setting so yes the oil made a big difference. It has also helped re=watching the video, I think it needed another load of coal putting in after coming out of the tunnel while coasting down the back gradient, another point I noted and in fact did point it out to the driver was that whereas I mainly had the regulator fully open he was pacing her more and this now makes sense for a number of reasons. First it means 4470 was conserving more steam and secondly it gives more time to attend the fire and water, Martin kept the water pretty constant whereas when i was at the controls it went up and down a lot. So yes I'm a little more confident that next trip will be a lot better, perhaps i may even get a complete 1/2 mile circuit without stopping... this is my next target.... Regards Pete ps: video www.dropbox.com/sc/ckgdjhhavde8ijp/WSg-u68IO5 of young Martin having completed a complete lap without stopping just before I get aboard, as he says he ran at 40psi around the circuit, this was what I found while steaming at home on the bench.. we could maintain 40psi all day non stop but not get the pressure any higher unless we stopped, so perhaps this was indeed down to the lack of oil for the two outer cylinders, effectively she was only really running properly on one cylinder... I'm beginning to feel more confident for the next trip.. hope it's not misplaced...
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