Baker Valve Gear
NW Mailing List
nw-mailing-list at nwhs.org
Wed Feb 11 23:25:51 EST 2015
>From experience and ease of maintenance the N&W found the Baker VG better for its use from the early teens to the end of steam. It even retrofitted some W-2 and M classes in the ‘20s. The late Walter Budwell, retiring as Master Mechanic on the Norfolk Division, told me that the Walschaerts was very simple and a good concept but required considerable more maintenance over time than the Baker.
The Baker was more expensive to purchase but since all the action involved linkages from pivot points, there was little wear on the Baker compared to the Walschaerts VG that had some sliding surfaces that wore from use over time. The sliding surfaces of the Walschaerts wore most where usually set for running; the term used by Budwell was it would “chatter” when excessively worn. Over time the worn parts had to be machined or replaced to bring back into tighter fit.
Bud Jeffries
From: NW Mailing List
Sent: Wednesday, February 11, 2015 5:53 PM
To: NW Mailing List
Subject: Re: Baker Valve Gear
Roger -
The trouble with going into reverse wasn’t with the Walschaerts on those roads – it was with the Baker. The CG 4-8-4s were equipped with Walschaerts. The center of their quadrants were blanked off because of engineers tending to hook the engines up too high which had bad effects on main rod back ends, etc., not associated with going into reverse.
The late Walter Dove who ran the 4501 when it was first resurrected in 1964 was notorious for hooking the engine up too hign; I’ve witnessed him running a hot back end on the 4501 which has Walschaerts and Consolidation 722, which had Southern (722 probably won’t run again, but 630 has the same valve gear); I had witnessed the same effect on a Y-6 on the Bristol Line from the same cause.
The popularity of Walschaerts VG, I’m convinced, had a lot to do with it being cheaper to put on the locomotive than Baker. Old Egide Walschaerts’ patent on the valve gear probably expired before the turn of the 20th Century, and anybody who wanted to design it and put it on a locomotive could do so. I had a MP guy off the Boston and Maine lament to me about the cost of buying Baker. (Penny wise, , ,)
But it had that sliding link block in a curved link (the Stephenson VG also had the links and link blocks) which was a little more complicated to maintain than Baker, all of whose connections were radial and therefore simple pins and bushings which could be maintained on a simple lathe (later McGill “Multirol” needle bearings).
IMHO, which might not be worth much, N&W liked Baker because when it was put right it would stay right, and when it got out of kilter a journeyman machinist could put it right using a lathe; in other words, it was a precise valve gear that would stay that way under all conditions.
It functioned just as well on an M as it did on a J; N&W’s Mechanical Engineers depended upon Baker to operate satisfactorily on its fastest passenger locomotive, which operated at a driving wheel RPM far faster than any of the other engines you might want to make comparison with. The only failure of a J relating to valve gear that I ever heard of was not the fault of the valve gear per se but of the power reverse. But N&W’s maintenance standards were pretty high, including reverse linkages.
The New York Central was another Baker road; it had hundreds of Mohawks, Hudsons and all its Niagaras so equipped; its early Hudsons that came with Walschaerts were changed to Baker, and if I’m not mistaken so were the Mohawks. They also had a bunch of H-10 Mikados with Baker, since Lima seemed to favor it.
Ed King
From: NW Mailing List via NW-Mailing-List
Sent: Wednesday, February 11, 2015 10:35 AM
To: NW Mailing List
Subject: Re: Baker Valve Gear
This is a very interesting topic. I had never heard that the Walschaerts would jump into reverse before. Possibly so.
It seems, though, that Walschaerts was a more common VG than Baker throughout this country and the world. I also understood that Baker required a royalty payment and was more complex and heavier with many more parts than WVG. Perhaps that could explain the popularity of the WVG? Personally I prefer the looks of the Baker and I'm glad to see N&W favored that type VG.
I read someplace that the Baker long travel (their term) was a very rugged VG and was more than able to withstand the forces generated by the more modern engines hence it's more frequent use in the declining years of huge super powered engines.
Who really knows? I'm sure Ed King, Louis Newton and Mr. Jeffries are about the best sources of info around though.
Maybe the WVG issue was why a lot of that type gear on many roads was operated with the screw wheel setup? I understand it gave the engineer very precise control of the VG.
Very interesting discussion!
Roger Huber
Deer Creek Locomotive Works
--------------------------------------------------------------------------------
From: NW Mailing List <nw-mailing-list at nwhs.org>
To: NW Mailing List <nw-mailing-list at nwhs.org>
Sent: Wednesday, February 11, 2015 7:24 AM
Subject: Re: Baker Valve Gear
Bob -
I’ve heard of this problem on the Southern. Engineers who tended to hook their engines up too close to center complained that it went into reverse, which might have been explained by too much slop in the reverse linkage. Engineers in the south seemed to be noted for this; when the CG got their 4-8-4s it was noted that a half-dozen or so notches either side of center on the reverse quadrant were blanked off so an engineer couldn’t latch the lever that close to center.
I don’t know that RF&P had that much Baker experience; if I recall correctly the only Baker engines they had were the 2-8-4s and the ex-N&W K-3s. Correct me if I’m wrong; there could have been some early Baker enginers . . .
EdKing
From: NW Mailing List
Sent: Tuesday, February 10, 2015 10:33 PM
To: nw-mailing-list at nwhs.org
Subject: Baker Valve Gear
Ed -
I recall hearing from someone a while back that the RF&P and maybe Southern had problems with the Baker gear as it tended to screw up when set near center. Maybe it was a specific class or application, I don't know, but I heard that and it came from a solid source. That said, obviously N&W figured things out nicely and took full advantage of what Baker had to offer in its attributes vs. Walschert or others.
Does any of this ring any sort of bell to your knowledge area?
Thanks.
Bob Cohen
I don't think any development of Baker Valve Gear occurred in the sense that you?re thinking about. The N&W got dissatisfied with Walschaerts gear early on with the E-1 Pacifics and M-1 4-8-0s, both of which (according to a long-time MP official who was a mentor of mine) that promoted rapid link block wear. The M-2s were slightly better, as were the Z-1 2-6-6-2s. You are referred to a treatise on valve gear in the ARROW entitled ?Monkey Motion?.
There was a predecessor of the Baker Valve Gear known as the Baker-Pilliod gear; it was applied as an experiment to class A 4-6-0 #89. It was used on the first E-2 Pacifics of 1910. The Baker-Pilliod gear supposedly gave quicker valve events for any given cutoff but was quite complicated. A simplified version of this gear, known simply as the Baker Valve Gear (Abner D. Baker invented the gear, it was marketed by the Pilliod Company of Ohio) came out about 1911 and N&W adopted it as standard. The Baker Valve Gear was patented and had to be obtained from the Pilliod Company. Some railroads didn?t think it was worthwhile. N&W obviously thought it was worth the cost.
As far as development was concerned, the Baker gear offered the advantage of providing a longer valve travel without introducing excessive angularities into the valve gear. After 1911 N&W never used another valve gear. The A of 1936 used Baker gear with a long valve travel. The only refinement thereafter was the application of McGill ?Multirol? needle bearings for all the connections in the gear.
When the J came along, I don?t think there was any question of using any other valve gear, or using poppet valves. The Baker valve gear driving the J?s big valves helped the engine to attain speeds of over 110 MPH (read Dave Stephenson?s treatises in the ARROW about the 610 tests on the PRR). Such speeds required driving wheel RPM in excess of 535, almost unheard of elsewhere. (Charles Faris designed the counterbalancing for the J; his figures were checked by Voyce C. Glaze whose workbooks are at the N&WHS Archives; the J might have been the most perfectly counterbalanced steam locomotive ever built, anywhere, anytime).
I hope this is helpful.
Ed King
--------------------------------------------------------------------------------
________________________________________
NW-Mailing-List at nwhs.org
To change your subscription go to
http://list.nwhs.org/mailman/options/nw-mailing-list
Browse the NW-Mailing-List archives at
http://list.nwhs.org/pipermail/nw-mailing-list/
--------------------------------------------------------------------------------
This email has been checked for viruses by Avast antivirus software.
www.avast.com
________________________________________
NW-Mailing-List at nwhs.org
To change your subscription go to
http://list.nwhs.org/mailman/options/nw-mailing-list
Browse the NW-Mailing-List archives at
http://list.nwhs.org/pipermail/nw-mailing-list/
--------------------------------------------------------------------------------
________________________________________
NW-Mailing-List at nwhs.org
To change your subscription go to
http://list.nwhs.org/mailman/options/nw-mailing-list
Browse the NW-Mailing-List archives at
http://list.nwhs.org/pipermail/nw-mailing-list/
--------------------------------------------------------------------------------
This email has been checked for viruses by Avast antivirus software.
www.avast.com
--------------------------------------------------------------------------------
________________________________________
NW-Mailing-List at nwhs.org
To change your subscription go to
http://list.nwhs.org/mailman/options/nw-mailing-list
Browse the NW-Mailing-List archives at
http://list.nwhs.org/pipermail/nw-mailing-list/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist6.pair.net/pipermail/nw-mailing-list/attachments/20150211/53e65a7c/attachment-0001.html>
More information about the NW-Mailing-List
mailing list