Ruby Valve Adjustment

[Anonymous]

I'm new to live steam having purchased a Accucraft Mimi this past October. As many have lamented, I had to spend a lot of time leveling the existing pike to facilitate live steam. This season I have had more fun and run time with the improved grade. I was dismayed recently when the engine performance began to get progressively worse (even with the pressure to 80 psi). When I put the engine in reverse, I was taken aback when it took off like a jet! I then learned about inside admissions and valve timing. I read Dave Hottmann's article on LargeScale.com, but after 4 hours of tweaking the eccentrics I'm starting to wonder if I am doing something wrong. I think I've got the preliminary optimal stall points, but before I start messing with valve adjustments to equalize the 3 and 9 dead center hesitation goal, I would have a better comfort level if there were any other more indepth explainations/experiences accessable in forums or elsewhere on the web. I guess I'm looking for a "for dummies" type explaination. I have some concern that the engine runs very rough in the new (inside admission) reverse position during air testing, which isn't a problem for me. My goal is to have it run at peak efficiency in forward gear. I just don't know what new behaviors are be expected.

Thanks,
Rich F.

[kstrong]

Unfortunately, there's no "Valve Timing for Dummies" out there. It's all trial by fiddle, and it's different for every locomotive, so settings that work for one will still be off for another.

Having said that, there are two points with the Ruby you need to fiddle with. First, there's the piston valve itself. There's a ring milled into the piston valve that should be even with the back of the valve block when it's as far forward as the eccentrics will let it go. There's a small locking nut that has to be loosened right behind the valve, and then you can rotate the valve (it's threaded) to set it to the proper distance.

With that set, then you can adjust the eccentrics.

But, it doesn't end there, either. You'll have to go back and fine-tune the piston valves, as the milled-in locator ring is more of a guideline than a rule. Run the loco slowly to where it stalls out. Then, bump the piston valve forward with your finger to see if that frees up the bind. If it does, then spin the valve forward a turn or two to see if that evens things out. If bumping forward doesn't help, try bumping it backwards a bit. (There's enough play to where a light bump will make a difference.)

I've re-timed three Rubys, and they all run differently. I've gotten them to run well in forward and reverse, but they've still got their own performance characteristics. Sorry for there being no "one-size-fits-all" answer.

Later,

K

[Anonymous]

Thanks for that advice. Is timing something that will need to be done periodically relative to run time? Good to know all engines have different characteristics. The timing procedure is probably something you get better at the more you do. Read your article in the June GR, and looking forward to the subsequent updates on your ambitious project. Looks like alot of fun!

Thanks again,
Rich

[kstrong]

Presuming the lock nut is tight against the piston valve, and the allen set screws don't slip on the eccentrics, then once you set the timing, it should stay set. You'll want to keep things lubricated so not to promote undue wear, but that's really it.

Glad you're enjoying the series (or at least the first part so far).

Later,

K

[Chompers]

Hey This Web site helped ALOT.

I have tuned my Ruby for Inside admition, and I too needed a little extra help.

Here is the link.

http://www.mylargescale.com/forum/topic.asp?TOPIC_ID=37632

Sincerly

Philip

[Smoke Stack Lightnin']

Hi Philip,

Thanks for the web site reference.  I spent at least 8 frustrating hours trying to fine tune the valve timing.  It seemed that no matter what I did, the stall position of the wheels would not remain consistent.  Bottom line though, my Mimi engine runs like a rocket!  It runs very slugish in reverse, but I don't care, reverse is not something I do.  I can now run with the tender, 3 AMS coal hoppers, a flat car, and a bobber caboose, with plenty of power to spare!  That engine is totally amazing.  The R/C servo on the Johnson bar is a must!  If I ever come in to a chunk of change, I would next like to purchase a live steam Shay!

Thanks again,

Rich F.

[Slick]

Back off on the pressure, 80lbs is Too Much......why has'nt your safety blown? (released)

[Smoke Stack Lightnin']

Slick,

I use an adjustable pressure valve.  Since my original post, I had purchased another gauge, and found out what is 80 on the original, is 60 on the new.  Another thing I seem to have to deal with is inconsistent flame, which slowly gets hotter into the run.  By the sound and response (R/C), I can tell as it happens, which is usually 5 minutes into the run.  Thats another reason I put as many cars on as possible, so I can run "wide open".  If I go too slow, the pressure increases (but smells terrific!).  When I try to readjust the flame lower, it seems to die out.  Also, sometimes I'm running in 20 degree weather, and sometimes in 90 degree weather, which has an effect.  Whatever- this engine is a blast as is!  I think live steamers all have different personality traits, if not out of the box, surely after we start tinkering around!  And I've logged some serious run time on her to date.  If she dies, I'd have to hope the next Mimi is just like her.  I doubt I'd be taking these liberties with a $3000 engine!

Rich F.

[Slick]

Hello, SSl,

      BTW, not a Greatful Dead fan, are you?

         I have two Rubies, one I ran for almost three years while cutting my teeth on livesteam and the other I've kept for spare parts....   The information provided by Dave Hottman and many others on this site will help you out greatly. The running you've done in tempreture extremes has illustrated little Rubies abilities, the responses you got out of her are what I'd expect.    Your next engine? I strongly suggest a Roundhouse, used or new......  You may also want to look at Regner's  "Willi", or even Aristocraft's Livesteam Mikado.  I own one of the Mikes, it runs great   (oh, not quite perfectly but darn near it)  and the price is about $1,500.    Whatever direction you go in Livesteam, enjoy it !

       Also, check out www.mylargescale.com, this site has an active livesteam forum and much info on Ruby and the like,  also yahoo.com has a Ruby group .

[Smoke Stack Lightnin']

Slick,

I watched a documentary recently on Howlin' Wolf, who was a delta bluesman that migrated to Chicago, and was quite a draw.  He wrote Smoke Stack Lightnin', and the actual steam engine footage from the 30's which ran behind the tune in the documentary was sensational!  So I was inspired to change from PRRRich to SSL.   The Dead probably did a version of HW's song, just as Clapton, Yardbirds, and many others have done.  Thank's for your suggestions on another steamer!  The problem is two fold; money and a horseshoe R-1 curve on my layout.  I'd love a Mikado, but don't think it would handle the R1?  I wish there was a live steam club in the Pittsburgh area!  I think my first choice for the next steamer would be a shay.  I have a banked area that would look great modeled like the switchbacks from the Cass Scenic RR (I'm into logging and coal operations).  I'd have to hope to find something used, but would rather purchase from someone at a club meet than ebay.

Look forward to your thoughts in the future threads!

Rich F.

[Slick]

Check out Regner's "Willi" or  "Konrad"...... They are mechanically  the same, the boiler layout is either verticle or horizontal....  both about $600.00.  Very complete engines, I quite tempted to do one or the other myself.....   Howl'n Wolf, eh, good stuff.   Your right, many have followed his lead. Best of luck....       Not fer nothing, I'm not a huge fan of  Evil-Bay,   some have better luck I suppose.

[Chompers]

I hate to burst your bubble, but a shay, won't go around a R1.  I think you need atleast 8' diamiter for the mechanism  not to bind.

But if you avoid the R1 spot, the shay could work.

 

[Smoke Stack Lightnin']

I was actually referring to a separate layout built into a hillside mostly comprised of straights and switches.  No bubbles bursting here dude, but thanks for R1 limitations.  I need to check out the specs on the Accucraft Shay.  Not like I can afford one right now anyway.  I have a Bachmann Climax (electric) that would do the job quite nicely. 

Rich F.