Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Jan 5, 2019 0:08:13 GMT
Rather than hijack Ed's thread where he's discussing Hydrostatic lubricators, I'd like to ask a few questions about what's the minimum delivery that's been found to be satisfactory. [snip]. Perhaps the subject of hydrostatic lubricators warrants a new thread? Despite having 3 x mechanical lubricators ready to fit to my Peppercorn A1, I'm now seriously considering going the hydrostatic route. I'd be very interested in seeing drawings of the good, proven designs that have been spoken about. Reg The conventional wisdom is that it is not possible to set a mechanical lubricator to use as little oil as does a hydrostatic one. A related issue is that for half of each revolution of the pump drive (which equates to a fair number of piston strokes) no oil is delivered at all, because most pumps are single-acting. I've only used mechanical lubrication so far, but for both reasons (not to mention inadvertently running the oil-gobbling pump reservoir dry on occasions!) I am attracted to trying hydrostatic and have fitted the necessary gear on my Paddington project. The cost of the surplus oil is scarcely an issue, but having it splattered over specs/goggles certainly is! Add coaldust and smuts to the goo and they become impossible to clean when out on the road... Gary |
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Post by mugbuilder on Jan 5, 2019 1:08:09 GMT
Thanks, thats some good tips. I might try my local metal merchant, I just figured they wouldn't sell small amounts. Don't know unless I try. Even if they say they will only sell you a length, do ask how much that is. You may be surprised at just how cheap Steel is. It's worth asking more than one if they aren't that helpful. There are two that I use, and they are both business like. They're happy to deal with me so long as it doesn't take long and I know what I'm looking for. The ones I use will chop it up so it fits in the car, but do take plenty of rag or something to protect the seats because it may well come covered in black grease. G, Day Roger, With regard to your lubrication question. I have found that using a Ewins type mechanical lubricator with 1/8" ram x 1/4" stroke and the top 'O' ring set down about 1/16" from the top of the ram stroke, about one revolution of the pump for about 25-30 revolutions of the wheel works out OK. Mind you ,this is to feed into a common steam line that serves both cylinders. I have used this arrangement many times with good results. I have also found that to much oil is better than to little. Regards, Barry
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dscott
Elder Statesman
Posts: 2,440
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Post by dscott on Jan 5, 2019 1:25:24 GMT
We have a Metal Stockist within Walking distance! Walking to but not back from of course!!
So strange that it also on the way back from the TRACK!!
Reason for buying the house again?
Close to the track and a Metal Stockist of course what else? 3.7 miles
Oh Yes Wickes, Toolstation, Screwfix and a paint supplier are also on the way to the track the other way round!
MOT garage walking distance from the track or Home. Always done on a Wednesday for some reason?
Lidl a bit further out adding 1/4 of a mile on the way home from the track! (That's for food but they also do some tools!!)
David, who loves to plan driving like we are doing a project in the workshop!!
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Lisa
Statesman
Posts: 806 
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Post by Lisa on Jan 5, 2019 6:51:46 GMT
More weight could be added by installing scale crew now it is becoming popular to get yourself scanned and printed in plastic? Have them cast in lead and half hanging out of the cab to give you firing room. A tubby Driver and thinner Fireman would do nicely! Dad had a Barbie doll in overalls as a driver in one of his loco's, the scale was about right. So the question I'd like to ask is can anyone estimate a figure for the volume required for say 1000 revolutions of the wheels for one cylinder on a 5" gauge locomotive? I say 1000 revolutions, because the amount for 100 revolutions is going to be almost unmeasurable. The question implies that a mechanical lubricator is the method of delivery, because that's what I'm using. I'm suggesting revolutions as a sensible measure of requirement, because some locomotives will have much smaller wheels than others. A bit of mild guesstimating and some maths suggest about 3ml per 1000 revolutions of the wheels for dad's sweat pea. Based on length of our portable track, laps per ride, wheel diameter, average rides per hour, size of the lubricator, and about how much I remember topping the lubricator up ever hour. |
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Post by Roger on Jan 5, 2019 8:02:08 GMT
Perhaps the subject of hydrostatic lubricators warrants a new thread? Despite having 3 x mechanical lubricators ready to fit to my Peppercorn A1, I'm now seriously considering going the hydrostatic route. I'd be very interested in seeing drawings of the good, proven designs that have been spoken about. Reg The conventional wisdom is that it is not possible to set a mechanical lubricator to use as little oil as does a hydrostatic one. A related issue is that for half of each revolution of the pump drive (which equates to a fair number of piston strokes) no oil is delivered at all, because most pumps are single-acting. I've only used mechanical lubrication so far, but for both reasons (not to mention inadvertently running the oil-gobbling pump reservoir dry on occasions!) I am attracted to trying hydrostatic and have fitted the necessary gear on my Paddington project. The cost of the surplus oil is scarcely an issue, but having it splattered over specs/goggles certainly is! Add coaldust and smuts to the goo and they become impossible to clean when out on the road... Gary Hi Gary, I'm not convinced by the argument about mechanical lubricators not being capable of using as little oil as hydrostatic ones. I hear what you're saying about delivery coming in waves, but i doubt very much if either system delivers oil that's in a mist. You're also ignoring the fact that the Hydrostatic systems deliver in drips that are separated by several seconds. My guess is that it dribbles into the steam chest and is thrown about and distributed in mostly oily form where it's carried around in droplets that get smeared onto the various surfaces. I can't see a short break in delivery having much effect even though the theoretical minimum delivery is different. I may be wrong, of course! Clearly it's better to have a smaller pump that's operating quicker for the reason you point out. The Jim Ewins design allows for a very small delivery for each stroke, and with a sprag clutch and adjustment on the arm, it's possible to set almost any rate of rotation. This is the main reason why I prefer this design to the LBSC one which necessitates a long stroke else the valving doesn't work. |
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Post by Roger on Jan 5, 2019 8:15:04 GMT
Even if they say they will only sell you a length, do ask how much that is. You may be surprised at just how cheap Steel is. It's worth asking more than one if they aren't that helpful. There are two that I use, and they are both business like. They're happy to deal with me so long as it doesn't take long and I know what I'm looking for. The ones I use will chop it up so it fits in the car, but do take plenty of rag or something to protect the seats because it may well come covered in black grease. G, Day Roger, With regard to your lubrication question. I have found that using a Ewins type mechanical lubricator with 1/8" ram x 1/4" stroke and the top 'O' ring set down about 1/16" from the top of the ram stroke, about one revolution of the pump for about 25-30 revolutions of the wheel works out OK. Mind you ,this is to feed into a common steam line that serves both cylinders. I have used this arrangement many times with good results. I have also found that to much oil is better than to little. Regards, Barry
Hi Barry, I'll try to work that volume out from the figures you've kindly provided. I've got a 3mm ram and 4mm stroke and I can adjust the delivery per stroke by how long the ram is. My intention is to make that as short as reasonably possible and run the pump faster to smooth out the delivery. I fully understand the sentiment about too little oil, but since it's not easy to determine what that means, I'm sure most lubricators deliver way too much. |
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Post by Roger on Jan 5, 2019 8:51:20 GMT
More weight could be added by installing scale crew now it is becoming popular to get yourself scanned and printed in plastic? Have them cast in lead and half hanging out of the cab to give you firing room. A tubby Driver and thinner Fireman would do nicely! Dad had a Barbie doll in overalls as a driver in one of his loco's, the scale was about right. So the question I'd like to ask is can anyone estimate a figure for the volume required for say 1000 revolutions of the wheels for one cylinder on a 5" gauge locomotive? I say 1000 revolutions, because the amount for 100 revolutions is going to be almost unmeasurable. The question implies that a mechanical lubricator is the method of delivery, because that's what I'm using. I'm suggesting revolutions as a sensible measure of requirement, because some locomotives will have much smaller wheels than others. A bit of mild guesstimating and some maths suggest about 3ml per 1000 revolutions of the wheels for dad's sweat pea. Based on length of our portable track, laps per ride, wheel diameter, average rides per hour, size of the lubricator, and about how much I remember topping the lubricator up ever hour. Hi Lisa, I'm glad that Dad had an equal opportunities policy both for full sized and scale drivers. I presume the guesstimate is for two cylinders, so 1.5ml per 1000 revolutions is the figure to work with. I'm surprised you had to top them up so regularly, was the tank very small? We run for many hours at the fetes and I'm not aware of anyone topping up the oil on any of the club locomotives. My tank is miles bigger than it needs to be, but it makes it less fiddly to get the mechanism in and out. |
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 5, 2019 9:10:13 GMT
I presume the guesstimate is for two cylinders, so 1.5ml per 1000 revolutions is the figure to work with. I'm surprised you had to top them up so regularly, was the tank very small? We run for many hours at the fetes and I'm not aware of anyone topping up the oil on any of the club locomotives. My tank is miles bigger than it needs to be, but it makes it less fiddly to get the mechanism in and out. Yes, two cylinders; if anything I've calculated a little more than was actually used, but the maths seems about right. We had a big tank on the lubricator, and could probably have run for 12 hours or more continuously without needing to top up; but it was just part of the standard 'rounds'. After an hour the tender was generally in need of water, so we'd top up the water, and while that was running top up coal, oil round, top up the lubricator, maybe top up the sand if there was a gradient, empty the ashpan, and give the brasswork a once over. |
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Post by Roger on Jan 5, 2019 9:22:26 GMT
I presume the guesstimate is for two cylinders, so 1.5ml per 1000 revolutions is the figure to work with. I'm surprised you had to top them up so regularly, was the tank very small? We run for many hours at the fetes and I'm not aware of anyone topping up the oil on any of the club locomotives. My tank is miles bigger than it needs to be, but it makes it less fiddly to get the mechanism in and out. Yes, two cylinders; if anything I've calculated a little more than was actually used, but the maths seems about right. We had a big tank on the lubricator, and could probably have run for 12 hours or more continuously without needing to top up; but it was just part of the standard 'rounds'. After an hour the tender was generally in need of water, so we'd top up the water, and while that was running top up coal, oil round, top up the lubricator, maybe top up the sand if there was a gradient, empty the ashpan, and give the brasswork a once over. Ok, thanks for that, it's a useful figure to have. Did you end up with oil around the chimney at that rate of delivery? |
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Lisa
Statesman
Posts: 806
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Post by Lisa on Jan 5, 2019 10:01:01 GMT
Ok, thanks for that, it's a useful figure to have. Did you end up with oil around the chimney at that rate of delivery? Not that I recall, and it was certainly never wet, though the cap wasn't so bright by the end of a long day. I do recall some particularly black faces when we first switch the sweat pea to a mechanical lubricator though; it took a few runs before we got the adjustment right. |
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Post by Rob on Jan 5, 2019 11:46:43 GMT
Personally, I think ME suppliers charge way too much, simply because they know most people won't approach Metal Stockholders. I agree. I've often thought it would be easy to set up a steel supply business that undercuts the typical model engineering suppliers if you can be bothered to invest the time in it and can strike a good deal with a courier. From my local stockist I can by 3 meters of something, cut in half to fit in the car, for the same price as the typical model engineering supplier charges for 12" when you factor in delivery charges. Even without the delivery it's still about three times as expensive as buying local. |
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Post by delaplume on Jan 5, 2019 17:47:12 GMT
Hi Roger,
Quote " Mind you ,this is to feed into a common steam line that serves both cylinders."........
I agree with this, PLUS that feed position must be as close to the outlet side of the Dry Superheater header as possible, and also with that outlet being in the centre of the tube where the steam velocity is greatest...
Hi REG,
Many years ago I ran a 5" gauge, Martin Evans parallel boiler Royal Scot ( Slide valve version ) which the builder had fitted THREE pumps onto the running boards.....and each pump discharged into a steam chest....
Result was massive over-oiling with me looking like a Dalmatian - Driver at the end of the day !!
I dumped the whole lot and replaced it with ONE commercial mechanical pump mounted under the front of the Smokebox and accessed by removing that part of the running board situated above the pump and between the mainframes when required.....The centre lamp mounting bracket proved ideal for this !!...........
The pump was driven by attaching an 1/8" welding rod to the eccentric for the centre Walshaerts valve gear......As this pump had to feed 3 cylinders I set it's output at MAX and the discharge as per above......
It worked perfectly and of course its' output was directly related to axle RPM...I'll see if I can find the photo...
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Post by delaplume on Jan 5, 2019 17:50:28 GMT
Here it is}---------- 
This is at the Rugeley track sometime back in the 1980's I think...........The pump mod is done and working---I designed, made and fitted the smoke deflectors and at this point have still to finish off the painting and livery.... Max. load encountered was}--- 2 passenger trucks with 10 adults on the drawbar PLUS a dead Simplex loose-coupled on the front (To be pushed back to the steaming bays via half the track circuit and going up the long bank.... As we reached the top of the bank I had both safeties lifting fully, 75% cut-off, both injectors on, firing on the move and regulator wide open !! and just a hint of damp on the chimney lip........ QED I think ?? |
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Post by Roger on Jan 5, 2019 18:18:58 GMT
Hi Roger, Quote " Mind you ,this is to feed into a common steam line that serves both cylinders."........ I agree with this, PLUS that feed position must be as close to the outlet side of the Dry Superheater header as possible, and also with that outlet being in the centre of the tube where the steam velocity is greatest... Hi REG, Many years ago I ran a 5" gauge, Martin Evans parallel boiler Royal Scot ( Slide valve version ) which the builder had fitted THREE pumps onto the running boards.....and each pump discharged into a steam chest.... Result was massive over-oiling with me looking like a Dalmatian - Driver at the end of the day !! I dumped the whole lot and replaced it with ONE commercial mechanical pump mounted under the front of the Smokebox and accessed by removing that part of the running board situated above the pump and between the mainframes when required.....The centre lamp mounting bracket proved ideal for this !!........... The pump was driven by attaching an 1/8" welding rod to the eccentric for the centre Walshaerts valve gear......As this pump had to feed 3 cylinders I set it's output at MAX and the discharge as per above...... It worked perfectly and of course its' output was directly related to axle RPM...I'll see if I can find the photo... Hi Alan, I've bet on the oiling working satisfactorily, feeding it into the centre of the piston valve. We'll see how that works out. My logic is that if I imagined doing this, what would I bet that the oil would pass through the valves and cylinders without depositing itself on the valve and cylinder walls? My guess is that there's no way you could stop it from getting everywhere. I suppose if it's fed into the dry header, it will have more time to end up as a mist, but you could argue that this is more likely to end up going up the chimney. It makes a much more elegant solution from a plumbing point of view if you can keep the smokebox and down pipes free from the oil feed pipes. As always, it's interesting to question the generally accepted view and try something different. |
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Post by delaplume on Jan 5, 2019 18:39:06 GMT
Hi Roger}---
Quote...Hi Alan,
I've bet on the oiling working satisfactorily, feeding it into the centre of the piston valve. We'll see how that works out. My logic is that if I imagined doing this, what would I bet that the oil would pass through the valves and cylinders without depositing itself on the valve and cylinder walls? My guess is that there's no way you could stop it from getting everywhere. I suppose if it's fed into the dry header, it will have more time to end up as a mist, but you could argue that this is more likely to end up going up the chimney.
It makes a much more elegant solution from a plumbing point of view if you can keep the smokebox and down pipes free from the oil feed pipes.
As always, it's interesting to question the generally accepted view and try something different.
NO--not INTO the dry header itself but ASAP into the header outlet pipe or pipes......This gives the longest possible tract for the atomised oil and steam to mix BEFORE arriving at the valve chest...
This might help}----
1) Try likening our steam lube method to that of a 2-stroke petrol engine ie}---- the oil and fuel are pre-mixed prior to actual use....
and then}--
2) The oil we use is NOT kept within the system but actually gets discharged --- as a mist --- into the atmosphere along with the exhaust....This is technically known as a "Total loss" system and can be found on Speedway motorcycles for instance.... ( I used to design and race similar Grass Track bikes within the Southern Centre ACU )...
Incidentally don't forget that there are different grades of "Steam oil" required dependant on the degree of Superheat employed.....
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Post by Roger on Jan 5, 2019 18:40:31 GMT
The riveting press was really only designed for the smaller rivets used on the bunker, but it's come in really handy for this tricky job with 1.6mm rivets. It's a long reach to get to the inside of the cab step support, and you can't get a rivet snap onto the back of it. I made a new anvil from 3mm Silver Steel then hardened and tempered that.
 20190105_130443 by Roger Froud, on Flickr The press worked really well, probably helped by the fact that the rivets are a snug fit in the holes and I've gone for a slightly smaller head. It was easy to get the anvils lined up true and then just squeeze them the whole way in one operation.  20190105_132352 by Roger Froud, on Flickr  20190105_132408 by Roger Froud, on Flickr  20190105_180452 by Roger Froud, on Flickr  20190105_180504 by Roger Froud, on Flickr  20190105_180512 by Roger Froud, on Flickr This is the first fitting of the cab stretcher/ballast weight and that fits like a glove. I've ordered some better length CSK screws for attaching the buffer beams though, the original ones are on the long side and it's easier to just buy a load more than shorten the ones I've got. Even with next to nothing attached to the frames this weighs a lot! I'm not sure if I'm going to attach the wheels to this, I probably won't bother. The boiler is going to be on and off quite a bit as I figure out the cab and piping details though.  20190105_180528 by Roger Froud, on Flickr The pump stretcher has had four M4 clearance holes, two either side of the pump so that I can attach a sturdy pivot point for an anti-roll bar. I may never fit one, but it certainly won't happen if I don't make provisions for it now. I've roughly schemed out a way of doing this, using spring steel rod in the same way it's done on cars. Personally, I can see both dampers and anti-roll bars being an improvement if I adopt the soft springing that I want for good grip. I don't want it rolling like a ship on the ocean!  20190105_102000 by Roger Froud, on Flickr |
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Post by 92220 on Jan 5, 2019 19:35:25 GMT
Hi Roger.
The results from your rivet squeezer are brilliant!! I must get mine made up as I soon have all the rivets on the smokebox to do. A squeezer will become invaluable for that lot!!
Bob.
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Post by Roger on Jan 5, 2019 19:46:04 GMT
Hi Roger}--- Quote...Hi Alan, I've bet on the oiling working satisfactorily, feeding it into the centre of the piston valve. We'll see how that works out. My logic is that if I imagined doing this, what would I bet that the oil would pass through the valves and cylinders without depositing itself on the valve and cylinder walls? My guess is that there's no way you could stop it from getting everywhere. I suppose if it's fed into the dry header, it will have more time to end up as a mist, but you could argue that this is more likely to end up going up the chimney. It makes a much more elegant solution from a plumbing point of view if you can keep the smokebox and down pipes free from the oil feed pipes. As always, it's interesting to question the generally accepted view and try something different. NO--not INTO the dry header itself but ASAP into the header outlet pipe or pipes......This gives the longest possible tract for the atomised oil and steam to mix BEFORE arriving at the valve chest... This might help}---- 1) Try likening our steam lube method to that of a 2-stroke petrol engine ie}---- the oil and fuel are pre-mixed prior to actual use.... and then}-- 2) The oil we use is NOT kept within the system but actually gets discharged --- as a mist --- into the atmosphere along with the exhaust....This is technically known as a "Total loss" system and can be found on Speedway motorcycles for instance.... ( I used to design and race similar Grass Track bikes within the Southern Centre ACU )... Incidentally don't forget that there are different grades of "Steam oil" required dependant on the degree of Superheat employed..... Hi Alan, I'm not sure there's any need to atomise the oil, all it has to do is get smeared on the moving parts. The more it's atomised, the more of it will pass straight through with the steam. I can't see how you can prevent the oil from getting everywhere. it's going to have to traverse through the whole system one way or another. I''m feeding it at the top of the centre of the piston valve so it will get carried along with the steam as each droplet forms. Time will tell, but I'll be amazed if there's an issue, especially as the piston valves are PTFE or Fluorosint. |
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Post by delaplume on Jan 5, 2019 19:47:04 GMT
Hello all, I've just shown this for interest sake...........Somewhere I have some photos taken in Swindon Boiler Shop showing an Hydraulic, Deep Throat riveter that looks uncannily like Rogers.... Great minds thinking alike ??............or can it be that young "Striplar" is gradually becoming a GWR chap   |
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Post by terrier060 on Jan 5, 2019 22:04:54 GMT
Hi Alan, I'm not sure there's any need to atomise the oil, all it has to do is get smeared on the moving parts. The more it's atomised, the more of it will pass straight through with the steam. I can't see how you can prevent the oil from getting everywhere. it's going to have to traverse through the whole system one way or another. I''m feeding it at the top of the centre of the piston valve so it will get carried along with the steam as each droplet forms. Time will tell, but I'll be amazed if there's an issue, especially as the piston valves are PTFE or Fluorosint. The atomising valve serves another function and that is to allow the oil to keep flowing during coasting and shut off the steam supply whilst stationary. |
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