Live steamer running slow???

Tag thanks for the info. I was using the Accucraft steam oil. Everything was oiled well. My friend had seen this on another Foreny although much worst. Ill have to contatct Accucraft about this and maybe get new ones. My friend is going to make better ones for me which should also give the engine more power compared to the stock ones. My friend explained to me how those particular valves are not that great but I forgt exactly. Ill have to ask him and get back to you. Its the same as the Ruby Valve design.
 
Shawn said:
Tag thanks for the info. I was using the Accucraft steam oil. Everything was oiled well. My friend had seen this on another Foreny although much worst. Ill have to contatct Accucraft about this and maybe get new ones. My friend is going to make better ones for me which should also give the engine more power compared to the stock ones. My friend explained to me how those particular valves are not that great but I forgt exactly. Ill have to ask him and get back to you. Its the same as the Ruby Valve design.
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I cannot think of a 16mm locomotive that does have piston rings. I have to say that I am baffled by this. perhaps your friend is thinking about that old canard that piston valves wear out and slide (or D valves) wear in. Properly manufactured piston valves, properly oiled will last the life of the locomotive. My old Merlin (nearly thirty years old) is still running ? although not on my tracks these days. I would most certainly have taken this locomotive back to the supplier. There are many thousands of these Accucraft locomotives running all over the world ? and the valves don't wear ? so there must be something wrong with your model. Take it back. Complain. Certainly Accucraft UK would do something about it.
 
Looking at a previous posting mention was made of the Accucraft Fourney sharing the same piston /cylinder assembly as the Ruby (the old ones ?). I have seen that an upgrade kit is made for the Ruby involving larger pistons by Accucraft themselves (or am I dreaming). This would seem to suggest that the supplied boiler is capable of producing sufficiant steam to support this mod'.

Still reckon a call to Accucraft is in order, if only to save yourself some time and money. Self improvement is a great thing but can end up being time consuming and self defeating.

Max.
 
Im still new to how live steam works 100%. My wording on things could be off. I guess saying stronger was a bad choice just better running then what it was.
This is from the SE Lounge forum on the issues with the Ruby but also applies to the Forney. The two that qoated the below are very knowledable with the Ruby. My friend has seen the same with his and others. Hopefully this will clear it up a little better. Sorry im still learning :confused:

"The main issue with the piston valves are they wear out the bore. They are a hard stainless in a brass block. Ive cleaned up the valves and then grooved them for Orings and they are much better off. The drilled bores are sufficient and flow more then enough steam. "
My feel is that the Ruby Piston valves have two other issues
1. they suffer with wear...they start to leak more and more.
2. the valve pistons are drilled through to allow steam (or exhaust) to pass from one side to the other. these passages are small and create drag reducing the efficiency. This is part of the reason the Rubys tend to run better "backwards" unless you fiddle with the timing.



My friend looked at my Forney and found some wear on the piston valves but not bad. The o rings where very hard though. He did replace them and the engine runs much better now. The other issue he found was the reverse valve. For some reason when it was set properly it ran very poorly. He is going to call Accucraft tomorrow and see what up and hopefully he can get more info for me. Its a good thing he is a accucraft dealer.
 
This is all very odd. The valves do not have O rings. They are precision ground to very, very fine tolerances. I don't think you could make replacements on a lathe, you need a cylindrical grinder to achieve the tolerance and finish. As Tag says, they run forever without wear provided they are lubricated correctly, my Mortimer has run many many real miles and does not leak past the valves.

Max, the Forneys alread have the larger Ruby cylinders, which are the same as the UK generic models use.
 
I wish I had a better understanding to explain better. Unless the Ruby and forney is made different from the UK models giving the reason for the lower price of the ruby and forney. (You pay for what you get). Not sure what he ment on the o rings unless he ment something else. Either way its fixed and running better. Hes not getting steam leakes out of the cylinder/valve area. This is all a learning experience for me and I Im learning a lot from you guys. Its great having a knowledable group with fast responces. I cant wait to see what accucraft says about all this.
 
Is it the valve body (block) which is brass that is worn out? That would make more sense with the piston valves being SS.

This could point to not enough lubrication with a loco as new as this?
 
Spule 4 said:
Is it the valve body (block) which is brass that is worn out? That would make more sense with the piston valves being SS.

This could point to not enough lubrication with a loco as new as this?
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It could of course. Either way the locomotive is being sorted by some guy down the road who thinks the design is wrong, so effectively one can no longer even have a stab at diagnosing problems. There are many thousands of Accucraft locos in this country alone and, oiled as per instructions, the bores will NOT wear. The piston valves are, in the honed bores, effectively running in oil. None of my Accucraft (and before that Pearse) locos have ever shown any sign of wear in the valve chests. All are still running today. While a couple have new running gear to to hundreds of hours running, none have received new steam chests. This machine should have gone back to Accucraft.

I would have taken it back ? but then it isn't my locomotive.
 
I think the "Ruby's run better backward" thing was related to early models with slip eccentric reversing rather than a reversing valve. In truth if your mate has had it to bits he's probably tweaked the timing, and that's whats done some good.
 
The engine is being sent back to accucraft. They want to take a look at it and fix whatever it is thats wrong with it. Hopefully in a few weeks I will have the engine back and fixed and with some answers for everyone.
 
Dtsteam said:
I think the "Ruby's run better backward" thing was related to early models with slip eccentric reversing rather than a reversing valve. In truth if your mate has had it to bits he's probably tweaked the timing, and that's whats done some good.
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The Ruby runs better in reverse due to the engine has outside admission of the steam in the valve chest as supplied by Accuraft. This can be changed by re-timing the engine with the eccentrics rotated 180 degrees, what this does is have the forward direction have inside admission, which makes it run faster in forward than in reverse, low speed running in forward can be made smoother. This change can be done to other Accuraft engines like the Shay's and the Excelsior. The Rubys valve gear has not changed to my knowledge, it has always had a reversing valve.
Thanks
Steve
 
steveciambrone said:
The Ruby runs better in reverse due to the engine has outside admission of the steam in the valve chest as supplied by Accuraft. This can be changed by re-timing the engine with the eccentrics rotated 180 degrees, what this does is have the forward direction have inside admission, which makes it run faster in forward than in reverse, low speed running in forward can be made smoother. This change can be done to other Accuraft engines like the Shay's
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Not wishing to drift this thread but that is interesting Steve. I have always wondered why my Accy 3 cyl Shay is such a sluggard. I never run it in reverse. OK, I know Shays are supposed to be slow, I am more thinking in the lugging stakes. Thank you Steve for the pointer.
Max.
 
Shawn said:
The engine is being sent back to accucraft. They want to take a look at it and fix whatever it is thats wrong with it. Hopefully in a few weeks I will have the engine back and fixed and with some answers for everyone.
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I think, undoubtedly the best course of action, even if it may take a little longer. If the guys who made it cant get it right, there's no hope.
 
I tried to find a reference page on making the inside admission change on My Large Scale but could not find it. There was a page which showed the procedure for doing it.
Thanks
Steve
 
Guys just a follow-up on this loco in question as I am the one working on it for Shawn. First the performance was ruled at either a jet or collar change as after cleaning the jet and moving back the collar it ran normal and was blowing off no problem when running on blocks. The engine had blow by when the Johnson bar was in center though, both forward and reverse had no blow-by. That was puzzling. When I took the valves out to check the center reverser had a lot of scrapes in the SS. That is pretty normal but it was much more then the cylinder valves them self. Also the scribed line on the reverser was far out of where it is supposed to be. In reverse it should be flush as a starting guide. This one was almost 3-4mm out. Covered in paint why it was not able to be seen well. So I first adjusted that thinking the blowby was caused by that but it was not, actually when adjusted flush there was no reverse and only forward. So I moved it back to being 3-4mm out and it was timed fine. I installed Orings on the piston valves to try and remove the blowby, Still no change in blowby in neutral, though running at pressure it was much stronger. After some discussion Cliff requested I send it in and he will have Bob take a look at it and most likely replace the valve deck as the only thing we can come up with is it the reverser valve block has warped somehow. Or the other possibility od the reverser deck is defective which is why the valve needs to be adjusted so far from the norm.


IMG_2977.JPG
 
kovacjr said:
Guys just a follow-up on this loco in question as I am the one working on it for Shawn. First the performance was ruled at either a jet or collar change as after cleaning the jet and moving back the collar it ran normal and was blowing off no problem when running on blocks. The engine had blow by when the Johnson bar was in center though, both forward and reverse had no blow-by. That was puzzling. When I took the valves out to check the center reverser had a lot of scrapes in the SS. That is pretty normal but it was much more then the cylinder valves them self. Also the scribed line on the reverser was far out of where it is supposed to be. In reverse it should be flush as a starting guide. This one was almost 3-4mm out. Covered in paint why it was not able to be seen well. So I first adjusted that thinking the blowby was caused by that but it was not, actually when adjusted flush there was no reverse and only forward. So I moved it back to being 3-4mm out and it was timed fine. I installed Orings on the piston valves to try and remove the blowby, Still no change in blowby in neutral, though running at pressure it was much stronger. After some discussion Cliff requested I send it in and he will have Bob take a look at it and most likely replace the valve deck as the only thing we can come up with is it the reverser valve block has warped somehow. Or the other possibility od the reverser deck is defective which is why the valve needs to be adjusted so far from the norm.
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Interesting. I suspect this to have been dodgy from new or has run with no steam oil in it ? worth checking tte lubricator to see that oil is actually getting though. I have never seen scrapes on the SS piston valves on Accucraft locos. They should, properly oiled, not wear at all. At a year old it would have been worth taking it back. Certainly replacing the steam chests/valves and setting up the timing on all three valves would be the best way forward.
 
As I said earlier, the correct action is now being taken.

I cannot see clearly from the photo if the 'O' Rings have their required clearance. Fitting 'O' rings is one thing, but if not fitted correctly they will not function for very long.

The 'ring' should be lightly pinched between the running surfaces, BUT, must have room to move up and down its groove (upto a third of it's dia), so that it rotates and changes its bearing point on each stroke, otherwise it will wear prematurely, and back to square one.
 
bobg said:
As I said earlier, the correct action is now being taken.

I cannot see clearly from the photo if the 'O' Rings have their required clearance. Fitting 'O' rings is one thing, but if not fitted correctly they will not function for very long.

The 'ring' should be lightly pinched between the running surfaces, BUT, must have room to move up and down its groove (upto a third of it's dia), so that it rotates and changes its bearing point on each stroke, otherwise it will wear prematurely, and back to square one.
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Yes the grooves are correct for the o-rings that are installed. 3mm ID 1mm section. There is sufficient roll and the compression is optimum 10% per Kozo's extensive article in Live Steam. The grove is .060" wide with a .0393 section width o-ring. Ive also built and sold 60 pairs of upgrade Ruby cylinders of 1/2" bore and they were the same specs again from Kozo. Piston o-ring along with the gland o-ring in the rear split head both had a 10% compression.
 
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