3/4-inch scale B&O P7d Cincinnatian

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Berkman
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Joined: Wed Aug 16, 2017 7:55 pm

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by Berkman »

all from the same casting set?

Would be neat if someone like Little Engines or Allen got those patterns and made them more commercially available.
bill4227
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Joined: Mon Oct 25, 2010 3:49 pm
Location: Taneytown, MD

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by bill4227 »

Here is the one in Baltimore @ Chesapeake & Allegheny
Attachments
DSC_8214.jpg
Andy R
Posts: 441
Joined: Wed Sep 26, 2007 2:18 pm
Location: So. Calif.

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by Andy R »

Many thanks for all of the replies so far!
Dave Dalton has been helpful on my build.
Dave's 5303 is of the 1927 as-built by Baldwin version. Such a pretty locomotive.
Mine is intended to be of the 1946 B&O modification of the 5303.
Andy R
Posts: 441
Joined: Wed Sep 26, 2007 2:18 pm
Location: So. Calif.

Drawings for the 3/4-inch scale P7

Post by Andy R »

The drawings that were included in the purchase included 57 blueprints (blue-background with white lines style), all dated 1931, in size 11 x 17, along with two larger prints of very poor quality dated 1965, and the frame drawing which is 11 x 22 or so. One of the drawings was the drawing list, which showed that a lot of important drawings were missing, including those for the cylinders, the rear frame cradle, the boiler, the cab, and the always helpful general arrangement drawings. I described what I had to John Kurdzionak, who told me that he too was missing some drawings, including much of what I have, and we could trade? So color copies were made and sent to John, and he sent me prints of the drawings that he had.

Sweet!

Mr. Coventry apparently revised his drawings (and created new ones with new drawing numbers) as late as 1965. Others who left their marks on the drawings included Ted McJannett and R.T. Hyslop. Dave Dalton sent me a spreadsheet of the various revisions – There were many, and his attempt to make sense of all the revisions was very helpful. Very helpful. As an example of the number of design revisions, I have four different spool valve designs that Mr. Coventry drew for this locomotive. Pick one.

I ended up making my own spreadsheets – three of them – a checklist of all of the parts made and to be made, a cross-reference to the different versions of the drawings in my posession, and a parts and castings list cross-referenced to the available drawings. I have printed copies of these in a 3-ring binder that I mark up whenever I finish a part. It is a nice way to gauge progress. If anybody is working on a P7 “President” and if I can find the files I will share.
Andy R
Posts: 441
Joined: Wed Sep 26, 2007 2:18 pm
Location: So. Calif.

More P7 Drawings

Post by Andy R »

Sometimes timing is everything.

I had a project in the middle of the state that resulted in a lot of auto trips past Grover Beach, so frequently took that opportunity to visit with Jack Bodenmann on the way home. Of course we talked about the P7, especially since he was then the caretaker of Doug Alkire’s 1-inch scale P7. Jack mentioned that he had Doug’s drawings, which were a jumble of rolled drawings in a very large cardboard box. I volunteered to "straighten out the mess", and Jack agreed, so for the next year or so, after work, and when time allowed, I sorted and scanned the drawings. I was lucky to have access to a roll scanner that allowed reproduction of Doug’s drawings, some of which were as long as the finished locomotive. Then a CD with those scans and the now-ordered and boxed drawings were returned to Jack.

Having copies of Doug’s design drawings helped answer a lot of my questions. I got to ogle Doug’s locomotive of course, and Doug was always an interesting conversationalist and a great source of information about the locomotive. Alas! He is no longer with us.
Pontiacguy1
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Location: Tennessee, USA

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by Pontiacguy1 »

Maybe when you are done you can post those on the IBLS website so they will be available to others in the future. Good luck on your project! I bet it's gonna be a real beauty.
Berkman
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Joined: Wed Aug 16, 2017 7:55 pm

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by Berkman »

Something about those 1920s premiere passenger trains. Very cool regardless of scale!
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Fender
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Location: Chattanooga TN

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by Fender »

Berkman wrote: Tue Jul 20, 2021 12:05 pm all from the same casting set?
My understanding is that the two in Baltimore and DaveD’s are all from the same patterns, I believe made by Bruce Hamilton. I don’t know about any others. Also, I have no idea what became of the patterns.
Dan Watson
Chattanooga, TN
Andy R
Posts: 441
Joined: Wed Sep 26, 2007 2:18 pm
Location: So. Calif.

castings for the B&O P7d Cincinnatian

Post by Andy R »

Examining the drawings that I had, the complexity of some parts appeared too great to try and fabricate, so a few castings were obtained from John at Friends Yankee Shop. The Brake Hanger Bracket #4134 in particular was a bit of a puzzle regarding how to hold the casting while machining, and in what order the machining was done. Adding to the consternation is the dimensioning - all relative rather than from an absolute reference. All connecting parts had to be consulted. In addition to supporting the brake hangers, these also support the main equalizers.
IMG_4199.JPG
I have elected to not (yet) finish any surface that does not need finishing. Paint will hide everything anyway.

Another casting set obtained is the brake hangers, part #8142. These are paired left and right. And holding them was also a puzzle.
IMG_4197.JPG
I may thin the web to the dimensioned 1/16 inch, but at this time it appears unnecessary.
Andy R
Posts: 441
Joined: Wed Sep 26, 2007 2:18 pm
Location: So. Calif.

another fabrication for the B&O P7d

Post by Andy R »

The Bumper Deck Plate Part #2130 was the only main frame member that was not included in my purchase. Keeping with the fabrication theme, I machined one using a 1.5 x 1.5 inch steel angle, and some plate, and then silver-soldered it all together. It was very time consuming.
IMG_4195.JPG
The bumper plate supports the pilot, forward coupler, and pilot beam, and secures the frame halves at the front of the locomotive.

Here it is bolted in place.
IMG_4196.JPG
The 2-56 bolts are long. I anticipated misaligning the holes, but all 16 were located, drilled, and tapped accurately, so no overdrilling and nuts are needed here. Most if not all of this will eventually be hidden.
Mike Walsh
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Location: St. Louis, MO

Re: castings for the B&O P7d Cincinnatian

Post by Mike Walsh »

Andy R wrote: Tue Jul 27, 2021 5:46 pm Examining the drawings that I had, the complexity of some parts appeared too great to try and fabricate, so a few castings were obtained from John at Friends Yankee Shop. The Brake Hanger Bracket #4134 in particular was a bit of a puzzle regarding how to hold the casting while machining, and in what order the machining was done. Adding to the consternation is the dimensioning - all relative rather than from an absolute reference. All connecting parts had to be consulted. In addition to supporting the brake hangers, these also support the main equalizers.IMG_4199.JPG
I have elected to not (yet) finish any surface that does not need finishing. Paint will hide everything anyway.

Another casting set obtained is the brake hangers, part #8142. These are paired left and right. And holding them was also a puzzle.IMG_4197.JPG
I may thin the web to the dimensioned 1/16 inch, but at this time it appears unnecessary.
Andy, I might have some of these castings (surplus to my needs). I am not sure if they are 3/4" or 1/2" - inclined to think 1/2", but if they are 3/4" and useful to you, you can have them free of charge if you're interested. Can you send me a PM with a photo of the brake hangers and brackets with a 6" scale next to them and I'll look in my shop?
Andypullen
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Location: Bel Air, MD

Re: 3/4-inch scale B&O P7d Cincinnatian

Post by Andypullen »

Fender wrote: Thu Jul 22, 2021 3:33 pm
Berkman wrote: Tue Jul 20, 2021 12:05 pm all from the same casting set?
My understanding is that the two in Baltimore and DaveD’s are all from the same patterns, I believe made by Bruce Hamilton. I don’t know about any others. Also, I have no idea what became of the patterns.
Yes, Bruce Hamilton built 2 P-7s. He used original prints from BLW and scaled them down to make the patterns. He had 4500 hours in each of his P-7s. I first saw them in the summer of 1978. 5300 was having the bugs worked out of her and 5301 was getting close to operation. 5301 now belongs to a member of the CALS. He's run it at many tracks around the country.

I've run the 5300 many times starting in the very early '80s. I believe that the castings that Dave is using were of the 3rd set poured from Bruce's patterns. Before Bruce passed away; he was talking with a number of people about selling the patterns, but nothing came of it. Mike Russo would know more about that. When he passed, the family decided to hold onto them.

Andy Pullen
Clausing 10x24, Sheldon 12" shaper, ProtoTrak AGE-2 control cnc on a BP clone, Reed Prentice 14" x 30", Sanford MG 610 surface grinder, Kalamazoo 610 bandsaw, Hardinge HSL speed lathe, Hardinge HC chucker, Kearney and Trecker #2K plain horizontal mill, Haas TL-1 lathe.
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