I found an write up on the Caprotti valve gear.

The main valve gear camshaft on both these locomotives is perpendicular to the locomotives direction of travel. The 4 plugged core holes (that are visible on the outside of the steam chest casting (on both the #49 and the #152 photos) are actually casting core holes that were threaded to accept plugs after the casting was finished.

The main shaft that drives the Caprotti valve gear is in-line with that largest core hole plug (seen from the side) and that puts the shafts exiting both steam chests on the same axis underneath the smokebox.

The reply that said; "the gear must be driven from the front axle" must be correct.

So does anyone have a photo showing how this gear could be driven from in front of the front driver axle?

I found this too, its the last mention of the Caprotti rights being bought or sold. This must be the company that owned and still owns the rights (and might have the engineering archive for all the parts).

•1945 Caprotti Valve Gears Ltd was merged into "Associated Locomotive Equipment Ltd" which now (then) concentrated on diesel electric traction.

The drive off one of the axles (which, depending on angles, may or may not be the first axle) is similar to that of a Spicer generator drive on a passenger car, although much beefier, of course. Appearance-wise, it would look something like the differential housing on the rear axle of a pickup truck. The diagram I have of a Reading 4-6-0 has this shaft offset to the left, and it's likely so here as well to clear the part of the equalizing mechanism that ties the leading truck to the forward driving axles.

I will try to scan part of this drawing in (my scanner is too small to take the whole sheet, which is rather large). I just have to get a round tuit (darn it, it seems all the tuits I ever see are square!)

It's surprising to me that a fair number of these engines for export had this valve gear. I wonder how that came to be?

While I'm trying to figure out my scanner and work out how to attach an image, here is the audio recording from 1949, courtesy of John Prophet and Semaphore Records, and a slide show to go with it, the whole works courtesy of "decoursey82:"

http://www.youtube.com/watch?v=x6HTHcouKu4

Also, some movie footage (silent) that also reveals the engines' combination of a dark green general color, with black running gear, in a way reminiscent of Southern Railway practice (though with a very different green!)

http://www.youtube.com/watch?v=u3PARLMJ ... re=related

Enjoy.

Still working with that !@#$%&()!! scanner; in the meantime, some photos of Caprotti engines in the US:

Reading 616, a rebuilding job from a locomotive built in 1905:

http://www.northeast.railfan.net/images/rdg616s.jpg

Reading 3010, a 2-10-2:

http://www.northeast.railfan.net/images/rdg3010sa.jpg

http://www.rr-fallenflags.org/rdg/rdg-s3010.jpg

B&O 5320, class P-9 (4-6-2), the 21st "President" class engine

http://www.northeast.railfan.net/images/bo5320s.jpg

Reading #616 4-6-0 and #3010 2-10-2 both appear to have the same Caprotti gear installed as the IRCA #152. Thats good to know.

Is there an archive for the Reading RR's equipment blueprints (drawings) that still exists here in the country somewhere?

You'll get that scanner going, just keep at it.

I believe the Reading Company Technical and Historical Society has quite a few locomotive technical drawings in their archives.

I contacted the "Reading Company Technical & Historical Society", the reply in below. It seems that most or all of the READING drawings are in the Pennsylvania State Archive.


Thats not good news, unless I was made of money, or I lived near PN so I could be a once a month Saturday Volenteer.

While looking up material on Vauclain compounds, I came across this video (in Italian) of a Caprotti cam box that might be of interest:

http://www.youtube.com/watch?v=pIK5mnd_h_U

yep, that looks like the culprit.

Make you want to build one of your own, doesn't it!

I went and looked at that list for the Penn State archives. That mechanical index has 53 pages of listings for different Reading Company diagrams. It includes seemingly everything the Reading ever owned, from rolling stock to locomotives. The only thing I didn't see in that list in my quick look through was any listing for a zamboni. I wonder if there are other archives for such technical drawings in the care of other organizations.

I just hope they (PN ST Archves) has this set (IRCA #153) when I get ready to search for them and buy them all,and I hope the carpotti steam chest valves & drive blueprints are there, but I have this gut feeling that they won't be.

I have enjoyed the discussion of what seems to show the FIdeCA 150-153 with Caprotti valve gear as delivered by Baldwin. I saw members of that class in the 1970's without the Caprotti gear.

Since a number of the posters seemed interested in the IRCA, and there was some discussion of the IRCA's relationship with United Fruit, the following might be of interest from a brief history of the IRCA that I compiled, primarily from their annual reports in the AAR library in Washington. In the Depression Era 1930's the previously profitable IRCA was headed into bankrupcy because it could not find long term financing for the cost of the new line from Zacapa to Salvador.

"Further trouble appeared in the form of an agreement between United Fruit and the Guatemala government for United Fruit to build a modern port at Concepcion del Mar on the Pacific coast, in return for United Fruit's right to develop a very large banana plantation at nearby Tiquisate. The expectation was that the bananas would be shipped via the Panama Canal. Moreover, the modern new port facilities would attract much of the profitable long haul coffee, sugar and banana traffic which IRCA heretofore had handled to the Atlantic port of Barrios. The outlook was not good.

"Then a dramatic reversal of fortune occurred with far reaching consequences for the railroad. The railroad convinced United Fruit that transcontinental rail movement via the IRCA to Barrios would be more efficient than ocean movement via the canal. Pending disaster turned into new opportunity. IRCA gained not only a major new source of long haul traffic, but United Fruit became a financial patron with deep pockets.

"United Fruit undertook a variety of steps, not only to save the railroad from bankruptcy, but also to re-equip it for its new task. The agreement with the government was renegotiated, eliminating the construction of a port as a condition. In 1936 the IRCA and United Fruit signed an agreement under which United Fruit paid off $2.6 million of IRCA's most pressing financial obligations in return for a 3-1/2 percent note for $1.75 million plus 186,000 shares of IRCA stock.


"In return for its financial support, the 1936 agreement provided United Fruit with preferential rates for movement of bananas from Tiquisate to Barrios. United Fruit paid $60 per car (later raised to $90) while competitors paid $130 for the same service. Further, the 186,000 shares of stock acquired in 1936, combined with a lesser stock position previously held, gave United Fruit a commanding 42.6 percent ownership position in IRCA.

"It should be noted at this juncture that the IRCA never was a "banana" railroad. Unlike many Central American rail lines that were built to carry bananas, the IRCA and predecessor companies were built to serve the general transportation needs of the region. Bananas generally produced 15 to 20 percent of revenues. Revenues from other exports such as coffee and sugar exceeded the revenue from bananas. And the largest single commodity group was imported goods. However, the long haul and trainload nature of banana traffic from Tiquisate gave it a uniquely important position in the generation of net profit while the traffic lasted."

More can be found at http://www.lifewastedchasingtrains.com/main.php?g2_itemId=947.

John West