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Boring Mill Q

Limy Sami

Jan 7, 2007
Norfolk, UK
It's Baldwin / Lima / Alco Loco works ;- What's the geared head working on the topmost of the 3 bores?

My thinking is that we are seeing a specialized two (2) spindle horizontal boring mill. It was designed & built especially for boring steam locomotive cylinders and steam chests (for piston valves). The caption describes it as a machine for boring " two cylinders & the steam chest at one time". I wonder if there isn't a third boring bar/spindle located behind the big boring bar and below the smaller boring bar on top. The idea would be to bore all the cylinders and steam chest on a casting in one single setup. In that way, all centerlines would be (theoretically) parallel, and all centerline distances worked off the same reference or datum.

In the photo, one boring bar, likely unseen rearmost, is boring the steam chest for a liner/piston valve. The other two bores are cylinders. Without a smokebox saddle on the casting, this may be a cylinder block for a Mallet type locomotive. As big as the cylinder bore closest the machinist is, it may well be a low-pressure cylinder for a compound locomotive. I am taking WAG's (wild ass guesses) here, but the casting may be rotated 90 degrees from the position it would be in on the locomotive. The flat flanged face would be vertical, the inset "step" (with the bar or tool laying on it) would likely be planed off to seat on the frame of the locomotive. The flanged face would join with a 'mirror image' cylinder block for the opposite side of the locomotive. Probably, this was a 'half cylinder block" casting for some compound Mallet locomotive. The 'extra" cylinder bore is a bit of a mystery. I wonder if this was a cylinder block for a Vauclain type compound steam locomotive. Samuel Vauclain was a chief mechanical engineer for the Pennsylvania RR, then worked for Baldwin. Vauclain had invented a system of compounding steam locomotives by "piggybacking" HP and LP cylinders, making two (2) cylinders on each side of the locomotive. The piston valve(s) for the two cylinders may have needed a larger steam chest as it may have utilized a 'valve within a valve' having concentric valves and some sleeve liners with fairly complex ports and even more complex cored steam passages in the block casting.
I wouldn't be surprised if that boring mill was built by Bement (the "Bement" of Niles-Bement-Pond), a Philadelphia machine tool builder. Bement made large machine tools, many of which were used by steam locomotive builders and by the rail roads in their maintenance shops. William Sellers & Co., also located in Philadelphia, was another big player in this niche. Harless Waggoner in The U.S. Machine Tool Industry from 1900-1950 comments that the end of the steam locomotive was a major cause of the decline in Pennsylvania's importance as a producer of machine tools as many of these companies concentrated on products aimed at the building and maintenance of steam locomotives.

Since the photograph came from a U.S. Civil War forum I'll add that both Matthias Baldwin and William Sellers were abolitionists.

I looked up the Vauclain Compound locomotives. This confirmed my WAG that the picture of the job being bored is the cylinder/valve chest block of a Vauclain COmpound steam locomotive. The Vauclain design used one single steam chest to handle the valving for the HP and LP cylinders, quite a complex piece of casting. Hence, it has a diameter almost that of the HP cylinder.

Sellers made feedwater injectors for steam locomotives, aside from machine tools. In their heydays, Sellers made machine tools for railroad shops and locomotive builders including wheel presses, slotters, wheel lathes, as well as locomotive turntables. Philadelphia and its surrounding area was quite industrialized in the 19th and into the mid 20th century. Not only locomotives, but shipbuilding, along with machine tools were all industries in and around Philadelphia. Some of the shipbuilders also made hydroelectric turbines. Baldwin had quite a history. Once they got to Eddystone, they subcontracted the manufacturing of military rifles for the US Army in WWI as well as England and some other foreign militaries. The US M 1917, known as the "US Enfield" was manufactured in large numbers and is known as an "Eddystone M 1917" rather than a "Baldwin M 1917". I believe Baldwin or possibly their neighbor, the Cramp Shipbuilding Company, took over the manufacture of what had been the DeLaVergne diesel engines. Westinghouse had a large manufacturing plant near Eddystone as well.

Some years ago, I was sent to take a course at the Electrical Power Research Institute, known as "EPRI". This is a research group run by participating electric power utilities and power generation and transmission equipment manufacturers. The course was held in a location called "Eddystone". It was in an EPRI building located within sight of the Baldwin Locomotive Works administration building. The old BLW administration building was one of the few buildings was left of the former Baldwin Locomotive Works, though I did not venture over to see who or what was left in that building. If my memory serves me, the old Baldwin powerplant building was still standing, but was fenced and off limits due to asbestos, with the building being boarded up or locked up inside a locked chainlink fence. The former Baldwin works infirmary or clinic was also still standing, but the building was vacant at that time. The adjacent real estate where Cramp Shipbuilding had been and where Baldwin had an 'export pier' was razed to the ground, though some active railroad yard tracks ran through the property. There was a lot of open land where the Baldwin shops had once stood.

I am guessing I was at EPRI sometime in the early 1990's. I have not been back that way since then. I think the old Baldwin administration/office building is now known as "the Baldwin Tower" and has been renovated and converted for new uses.
I thought Boeing Rotorcraft Systems (nee Vertol) had some of the old Baldwin Eddystone property and buildings.

Eddystone is also famous for Philadelphia Electric's Eddystone Unit 1, an ASME landmark super-critical steam power plant running at 5,000 psi and 1,200°F when first opened. It closed down in 2011. I got to tour it in the mid-70s. It was equipped with pneumatic controls IIRC.
I'm wondering if the gearing on the upper boring bar is for generating some special feature inside the valve chest like a spherical relief or other recessed shape somewhat along the lines of this one from an old I.C.S. text.


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Now Joe, you’re sending me into a time wasting morning session looking thru drawings while off work today ;-) Just looked at my copy of original Baldwin blueprint of the Denver Rio Grande K27 that was made as a Vauclain and later rebuilt as a simple expansion. The K27 and other Vauclains I found pics of in quick Google search all had low pressure cylinder on top. Presumably for clearance reasons. Looks like Limi’s pic shows low pressure at bottom. Doesn’t mean it isn’t Vauclain, just atypical?
I think that Joe Michaels' thought -- that the casting orientation on the boring machine is rotated 90 degrees (about a line parallel to the three cylinder axes) clockwise (as we view the photo) from its on-locomotive position -- is correct. Put another way, photograph right is locomotive up.
I had seen other information about Baldwin Locomotive Works in the past on the Internet archive so when I noticed this book I tried a search for "compound" and turned up this page .
Many of the images do not show up on my screen so either they are not there in the scans or it is my system that isn't co-operating .
Maybe some of the other links in the search will turn up something better if someone is interested to explore more.
This image did copy
P.S. there are some cylinder illustrations in this book


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What is traversing the tool(s)? It looks like the workpiece is on a table with some rather narrow ways right above the floor?
If the table did not have enough travel then they may have used a traveling boring head "h" as shown in the image copied below taken from here.
Scroll back a page or two for the description .
That would also allow for shorter stiffer boring bars but as mentioned by John Garner may be more prone to parallelism errors.


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