This is pretty fascinating stuff.

Does the shaft that runs from the eccentric to the valve check rotate, like a drive shaft?

Also, has the shaft on the engineer's side been torched off where it would meet the eccentric crank? It certainly looks like that in the picture.

Very cool to see an update on this locomotive; thanks for posting.

So is the valve gear literally set up for only two positions, or does the reverser allow adjustment? I'm wondering if the lever doesn't work like the one on locomotives like CP 4-6-4 2839, which had a wheel reverser with an air motor. You could manually turn the wheel for fine cutoff adjustments, or push a lever to actuate the air motor for major adjustments. I.E.- you'd push the lever forward for a few seconds which would spin the reverser wheel forward putting the locomotive in full forward gear, then return the lever to "neutral". Maybe 611 has something similar without the wheel. Of course there'd have to be some kind of cutoff indicator in the cab so you could tell how the gear was set. One of the guys at TVRM had indicated previously here that the 611 had some "simplified" form of Franklin poppets, so maybe it only is 2-position. I guess it's possible 611's gear does some sort of automatic cutoff adjustment. I'll be very interested to read what you guys turn up.


Yep, it rotates just like a drive shaft. Worm gear at the eccentric turns the drive shaft which turns another gear in the cylinder assembly which rotates a camshaft, mounted parallel to the engine's axles, which opens and closes the valves. Each cam lobe is wide with a varied profile. Reversing and changing cutoff are achieved by sliding the camshaft from side-to-side, which causes different parts of the cam profile to work the valves.

Look on youtube for videos of the UK locomotive "Duke of Gloucester", #71000. It uses Caprotti rotary cam valve gear, which is very similar. You can probably find some close-ups where you can see the driveshafts rotating.

I couldn't tell from the pictures that I was sent if it was the cam shaft or the suspention link, so I called down there and chatted with my contact. It is the cam shaft that has been cut. My contact told me that they had just cut it with a torch, but the shop is going to be making two new shafts anyway. I guess that the Universal U joints are all bound up and prety shot. Won't know for sure until I get down there to take a look see for myself. That won't be until at least August due to the schedual of things down there.




That is the $20,000 question that a bunch of us are trying to answer. None of us (who have worked on steam) have ever worked on type D franklin gear, so....this is the best answer I can come up for you at this point.

We have not torn into the valves themselfs (at the cylander). So from what we have done so far, this is what we have gotten. The adjustment to the valves is done at the valve. There is no adjustments on the eccentric boxes as you can see from the pictures, and no air fittings that would do anything to the gear inside the cam boxes. All of the adjustment to the timing of the valves has to be taking place in the valve casing itself. So as far as any adjustment at the cam box via the eccentric crank....yes. It is literally only set up for forward, neutral, and reverse.
I would be very interested to hear from TVRM if they had gotten into the valve chests. Maybe they have some more insight. From everything that we have seen so far, the type D seems to be an "on"/"off" simplification of the type A and B gear. No way to really tell until we tear apart the valve chests. The boys are going to go out after the 4th holiday and tear into the R3 eccentric case and see what it's made of. That will be the difinative answer as to weather or not there is any adjustment capability in the cam boxes via the eccentric crank. I'm really leaning towards it being an "off"/"on" system. Mostly due to the fact that the army was trying to sevearly simplify the operation of the S-160 class.

Brett,

Thanks for the update! This hits many "sweet spots" of interest for me, WWII military locomotives, the S-160 class, the Transportation Corps and Franklin Valve Gear, to name a few.

Looking forward to more updates.

Brett- that piece that is cut off is a driveshaft, not the real camshaft. The camshaft itself is inside the cylinder block. When I say the camshaft could be moved I mean the part inside the cylinder blocks. The camshaft is mounted in the cylinder block parallel to the axles. The driveshaft has another worm gear at the other end (inside the cylinder block) that turns the camshaft.

Here's a link to Franklin's patent for the Type B poppets (the first rotary cam ones they had):

http://www.google.com/patents?id=_RFLAA ... ve&f=false

Look at Figure 11 on page 5; that shows a cross-section through the valve gear above the cylinder looking towards the back of the locomotive. You can see the cam shaft, with the driveshaft and gears toward the left end. The gear at the top of the cam shaft (towards the middle) moves the cam side-to-side and that reverses the action of the valves and/or changes the cutoff.

Clearly the reverser shown in this patent is very different than the one on 611, so the patent doesn't do anything to help figure that out.

I'll look later and see if I can find a patent for the Type D, but I'm pretty sure I've looked before and haven't been able to find anything. Surely some technical info must exist somewhere on this stuff.

Dim recesses of memory I recall reading something a long time ago about poppet valves with automatic adjustment of cutoff....I just can't recall details like if it was on Type D or even Franklin gear. I'm sure some documentation will turn up somewhere.

dave

I'll change the nomenclature on my notes. Some of the terms we are using may not pertain to the nomenclature that is accepted as the norm because we are working off of only what we have been able to find in the Army notes and such. Please forgive the misnomer if there is a better accepted name, and I will change what we are using so that as I explain what we are doing and what we are finding everyone can understand it. Sorry about the confusion whodom. I will change the drawings to reflect drive shaft, not cam shaft.





This is where things are going to get quite sticky for everyone that is interested in this valve gear or this locomotive. We will all have to help with the reverse engineering of the thing if it is to ever run again. If you can find something on the type D, I would very very much appreciate it. I have looked and looked and looked, even went to Ft. Useless....er.....I mean Eustis and came up with a big old goose egg at Hanks yard, and at the museum. There is nothing left of the mechanical notes on this engine.





The big issue that I am running into (and everyone please correct me if I'm wrong) is that at this time in the early 50s, the army kept a lot of this stuff close to their chest. Everyone else was working on Diesel technology, the Army was still trying to make the S-160 class a deployable asset. Even going as far as fixing design flaws in the S-160 (such as issues with water legs, arch tubes, and grease cellars and crown stays in the firebox) to create the S-160A Class (the most famous member, and only survivor, of the S-160A Class is TVRM 610) Most of the modifications to the locomotive that made this a "type D" locomotive were not really documented, or replicated. As far as I am aware, the #611 is the only locomotive in existence (at the very least in the US) with type D gear. So there is really no place that we can go to to reverse engineer it. Kind of have to do it by the seat of our pants. And of corse with the help we are getting here.

Thanks to everyone for the interest. Please keep the ideas coming, we are going through every "Have you thought of" or "Have you tried" as we can.

Brett-

Here's a later patent for Franklin "long compression" rotary cam poppet valve gear which has some better drawings in it. There's no telling if 611's gear is the "long compression" type or not but all the pieces should look similar. There are some good illustrations of the camshafts so you can see what I'm talking about.

http://www.google.com/patents?id=HoBWAA ... on&f=false

AFAIK 611 is one of only 2 locomotives left in the U.S. with any kind of Franklin poppet valves. The other one is C&O 4-6-4 #490 in the B&O Railroad museum in Baltimore. 490 has the older "Type A" poppets which are actuated by oscillating cams driven from a box actuated off the cross head. The valves themselves are probably almost the same as 611's but all the other parts will be different.

So, Franklin developed Type A poppets in the early 40's, Type B poppets (with rotary cams) around the mid-1940's, long-compression poppets (Type C???) in the late 40's (never actually applied to a locomotive AFAIK) and apparently Type D poppets in the early 50's.

The fact that this gear is called Franklin "Type D" must mean Franklin was involved in the development so maybe that's where some information can be found since there don't seem to be any Army records left. I'm pretty sure I've seen information on Franklin archives someplace. I'll keep looking and let you know if I can find anything.

[Edit: update]
While googling for info I immediately hit on this old thread on RyPN about 611 started by Mark Ray from TVRM.

viewtopic.php?f=1&t=18455

They weren't able to find anything either, but one guy (Wolf, see the last post) hit on something that may be a big clue. Vernon Smith's book (Mr. Smith worked for Franklin) mentions a system they developed with automatic cut-off adjustment. I'll get in touch with Wolf and see if he's run across any additional info in the last 7 years.

Thanks again for posting the pics and information on this locomotive. Maybe I WILL get to hear the exhaust of a poppet-valve equipped steamer one of these days!

Darn, wish I could help out more, but I didn't inherit millions of dollars. . .

Looking at the drawings, and reading the comments, and also thinking of the 3463, I can't help but think of "muscle cars" and "hot rods," and their builders talking of cams, cam profiles, and the like.

It's interesting to note, but starting with some Formula 1 gear some years ago, the people in the automotive-internal combustion arena have been looking at technologies--including solenoids and pneumatic devices--to give internal combustion engines variable valve timing. Boy, are they behind the times; we steam locomotive people have had variable valve timing almost since the beginning of steam traction nearly 200 years ago!

Am looking forward to seeing (and hearing) this locomotive as well. . .and she's within range for me. . .thanks, Mr. Miller. . .

Hugh,

The later patent you found is a little bit closer to what is actually on the engine, but still not correct. I'll go through what we know on these drawings, and hopefully we all can decipher this a little bit more.

There are 1 or two similarities, but that's about it. 611 does not have the reverse quadrant, power reverse cam, the reverse shafts, the transverse gearbox, the transverse shafts or transverse u-joints to the forward cam shaft, the external valve cam boxes, or the forward cam box on the valve chest. On 611 this is all done by air. Exactly how that all happens....until we get everything put back together and hook it up to a compressor to chase the lines....who knows. The Cam boxes shown in that drawing that are outside of the valve (meaning not in line) are not the same as the ones on 611. On 611, the drive shaft goes to the cam joint that is in-line with the valve. There is an assembly that (I guess you could call a box) fits in-between the two branches of the dry pipe to the valve. It extends over the valve and down to half way over the piston. There is an access door in it about 3/4ths of the way up, just before it begins to curve over the top of the valve between the branch pipes.

The more and more I think about it.....I like the quote from Wolf



This seems to make more and more sense since the Army would have liked this for ease of training on the locomotive. No need to teach new guys fresh out of basic how to "hook up" or "trim steam" if the system is all self contained within the valve and cam itself. This really has me thinking now....the more and more I think about it, maybe I am going to have to pull the cam shaft and valve covers when I get down there to put this to rest. That and I'm just getting more and more curious as we go.
Now if this is the case (and in line with Wolfs assertion), there must be some way that the valve stem and rotary cams are sprung so that with the increse in spead at an exponential rate, the cam will close the valve at varying points of the piston stroke. In the all the patent drawings and information supplies so far, this function is still done by the power reverse with a quadrant in the cab.





I will stress now that there is no timeline for bringing the engine back to operation, but that is slowly becoming an option. Originally Bill bought the equipment just to cosmetically restore it, but with all of the interest this locomotive is generating (and the fact that it is highly likely that it is the only engine in the world with Type "D" Franklin gear) there is a movement towards steaming it again. At the very least though I will continue to post things as we move along. It will be in spurts, as they work on it as time and funds permits. They have to run the business in order to pay for their Army Steam habit.....lol.

Here is the caption from Vernon L. Smith's book "One Man's Locomotives":

"...an Army standard 2-8-0 engine, originally road No. 2628, built by the Baldwin Locomotive Works in 1943, builder's No. 69856. It is equipped with a special Franklin rotary cam poppet valve gear. The locomotive was designed for operation by an unskilled engineman in that the reverse gear lever is arranged to latch only in full forward, center, and full backward positions on its quadrant. As the rotative speed of the drivewheels increased, the cam design was such that the effect of hooking up, to work steam expansively, was automatically provided. The locomotive was renumbered later to No. 611..."

I would look for some sort of flyweight governor mechanism at the camshaft which would serve to laterally displace the cam as speed increased and thus alter the cutoff.

Vernon L. Smith was a designer at Franklin who worked on the Pennsy T-1s and a few other projects and later was employed by the Santa Fe and applied the Type B valve gear to 4-8-4 # 3752 - which by the way worked very well, but it was too late in the game to halt the transition to diesel...of all people, he would have had some knowledge of the project...unfortunately, he passed away a few years back.

If you haven't already, you should check out the Lima (owners of Franklin) archives at the Allen County Historical Society and I believe the California State Railway Museum has some of the Lima documents in their library as well...

Please keep us informed about progress on this project...I'm in Southeastern PA and would love to come check out the locomotive at some point...

You might not need to reverse engineer it. Unless somebody has done significant damage to the innards of the box, or torn it down without documenting where the bits go, just carefully cleaning and lubing it may be all that's necessary to make it work - and, once it is working, then you can see exactly how it works.

Also, just because you haven't found a place to go for documents to reverse engineer it, doesn't mean there isn't one.

There's a lot about quantum theory I don't know, but that doesn't mean it doesn't exist.

dave

Well, based on Wolf's post it sounds like Mr. Smith's book nails down the idea behind the valve gear on 611 and hopefully this means there's additional documentation somewhere. I believe I've seen reference to someplace that has Mr. Smith's papers, so maybe those can be accessed for additional information.

I'm trading e-mails with the guy at the Allen County Historical Society. He gave a quick look at the Franklin Railway Supply papers they had and didn't see anything relevant, but he said he had a whole bunch of Railway Mechanical Engineer magazines and he'd do some additional searching. I'll let you know if he comes up with anything.

Thanks Hugh,
I really appreciate all the help. The issue has never been getting information on the "Franklin" gear system such as the A and B, but on this ultra rare (lokking more and more like) 1 of a kind application. I'm glad that the description by Mr. Smith echos what I had been proposing for the general idea behind this system as it validates a lot of my points to this subject.


The thing to remember about this (even getting more than a passing referance to the locomotive) is that this system was commissioned by the army as a one off experiment. I have the feeling that a lot of the modification was done by the seat of their pants, and this would be a valid and plauseable explination as to why there are not a lot of papers on it.



Dave,

I will have to agree with you in premise, but, so far experiance is dictating that when the army tells you "it doesn't exist" it means one of two things. Either it really doesn't exist, or you do not want to get caught looking at it. I'm inclined to lean towards the first part, as I don't know why type D valve gear for a steam locomotive would still be classified......Stranger things have happened though. They have drawings and information up the backside about the S-160 class.....and even about 611 up until the conversion. After the conversion....nothing. Things that make you go Hmmmmm......

Here's what the railroad guy at the Allen County Historical Society turned up so far:

"Found a picture of it, in a book by George W. Hilton in 1963 on the Ma & Pa Railroad, regarding Franklin poppet valve trial.

Also, picture in Trains Magazine , September , 1950 mentioning it was built in 1943 by Baldwin, and rebuilt by Vulcan Iron Works in Wilkes-Barre , Pa. No follow up found in Trains as to how the trial went. Does mention possible use in Korea as to why testing poppet valves.

I'll check with a couple of people I know , to see whether or not they have any knowledge of the locomotive."

So there's another lead worth following up: perhaps we'd find something in the records for Vulcan? I'll post up if he turns up anything else.