Steam Locomotive Ultra-Detailing in “O” Scale…PRR I1sa #4390

Even though I do a LOT of scratch building and brass bashing for my own railroad, in support of both my D&H and Erie fetishes (you gotta roll your own if your’re going to model steam for either of those roads), I also regularly take on commissions for other clients from both the U.S. and overseas.

This past spring (2010) I took on a box-stock US Hobbies PRR I1s project. The client, a physician from New England, wanted this loco as accurately detailed as was humanly possible. Using detailed images from the period for this loco, I took this generic Penn I1s and totally reworked it into ultra-detailed PRR I1sa #4390, as she appeared in 1953.

Ultra-detailed backhead and boiler of I1sa #4390 (click on image to enlarge, and then click again)

Backhead of #4390 after initial detailing…

Partial cab interior and boiler viewed from Fireman’s side (note the addition of the reach rods from the starter valve and the injector on both the steam supply and water dump sides of the valve). This is how the Fireman controlled these components without leaving the cab…

Broadside of Fireman’s side of the boiler, with details for this section of the boiler nearing completion…

Fireman’s side front end after having received the “WWII Beauty Treatment”…

Engineer’s side front end showing many additional details, including the Turbo-Generator exhaust steam pipe and standoff, that connects to the generator and exits along side the stack (an often overlooked detail)…

Boiler is regularly test-fit to the chassis during the detailing process, ensuring that proper running clearances are maintained between the new boiler details and all moving parts, i.e. drivers, rods, valve gear, etc…

Belpaire topside details showing the addition of the two reach-rods and rod-guides that control component steam supply. The rods penetrate the front cab bulkhead, and end over the top of the crew’s head. Their red handles can be seen in the very first image in this section.

The arching whistle chord and guides from the whistle’s accuating lever and back to the Engineer can also be seen. This chord is made from 0.005 brass wire that has been anealed, formed and re-hardend, which allows it to take on and maintain this shape.

Here are all the components cooling, having come fresh from the paint oven.  All parts are baked at 175 degrees for three hours to cure and harden the paint. Paint for this model is ScaleCoat PRR Brunswick Green (DGLE). The paint is not applied directly to the primer coat, as it is too green from the bottle. Instead, after priming, the entire loco is first painted semi-flat black, and that coat is then baked. 48 hours later, the Brunswick green is applied.  Doing this dramatically darkens the green top coat to a near-black. Later, after lettering and clear, matte top-coat, this near black color throws off green hues in both natural and artificial light, just as a fresh, PRR paint job would have done on the prototype.

210-F-75b tender for #4390 nearing completion. It still lacks a tail light, marker jewels, and cab glass…

The completed I1sa #4390. Both the locomotive and tender were given a pristine, factory-level plus paint job and lettering. Per the customer’s request, no weathering was applied.

The completed I1sa #4390. Ready to ship to the customer…

Re-detailed with Post WWII front end…

Engineer’s side…

Fireman’s side…

Tender detail 3/4 view…

Water line hose connection detail to injector and Worthington BL4B feedwater heater…

This entry was posted on Sunday, August 8th, 2010 at 3:06 pm and is filed under Client's Projects. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

14 Responses to “Steam Locomotive Ultra-Detailing in “O” Scale…PRR I1sa #4390”

  1. Geoff Says:

    Nice!!! Too bad it is Pennsy……

    More, we want more!

  2. Matt Forsyth Says:


    NOT MY road, but a loco that was done up for a customer. What the customer wants, the customer gets!!! There is more on the way. I know you want more D&H content, me too, but I gotta pay the bills. Currently in the que there is a…

    Lehigh Valley T-2b, 4-8-4
    PRR N1, 2-10-2, and
    N&W S-1a, 0-8-0


  3. Mike Cougill Says:


    I was born too late to see steam in work-day mainline settings. I grew up on the Pennsy’s Columbus (OH) to Indianapolis Division where they ran every class of engine they had, with Mountains, J’s, H9-10’s and K4’s being the most numerous. I’m told that the I1’s were used on the GR&I north out of Richmond due to a stiff grade leaving town to Ridgeville, IN. Doubling the hill was not unknown and must have been a sight to see. Your model is superb in workmanship and execution.


  4. Matt Forsyth Says:

    Mike Cougill [quote]:
    “Your model is superb in workmanship and execution.”


    Thanks so much for the compliment. I strive for extreme accuracy and an excellent fit and finish.

    Yes, seeing PRR I1’s in multiple must have been something. I am fortunate to have a friend that actually saw them stomping up the hill near Trout Run, PA enroute to Southport, NY (near Elmira) on the PRR’s Elmira Branch. It was not unusual to see two, three or more wrestling a 100+ car loaded hopper train north.

    Impressive indeed!!


  5. Matt Forsyth Says:

    An off-site comment from Ed Reutling…

    “Nice, nice, nice update! NOW, I wanna see some bench work and a loco and cars running! BTW, that’s some model. You going up against Kohs?”

    Ed Reutling

  6. Pete Says:


    I1sa #4390 is one of the most beautiful pieces in my collection, right up there with Kohs quality, only with a personal touch. You delivered more than I could have ever expected. I stare at that beauty every day. I’m proudly looking forward to more of your work becoming a part of my collection.


  7. Bud Rindfleisch Says:


    Nothing short of superb! The Pennsy dec’s were always one of my favorite prototypes, and I’m fortunate to have the last remaining example of the 598 built, about 4 blocks from my house! Opinions are usually mixed as to which tender looks best behind the beast, but my vote is for the 210-F-75. It makes the engine look beefier too! Excellent workmanship, paint job too!

    Also good to see your “list in the que”!

    Bud Rindfleisch

    Hamburg, N.Y.

  8. Neville Rossiter Says:


    Your workmanship would be right at home in the English magazine “Model Railway Journal”; a magazine that accepts only the best. I can only describe your work in three words.

    “Exceptional Creative Achievment”.

    You take care mate, and thanks for the update. I learn something everytime.


  9. Bob Courtney Says:

    What a gorgeous model of a good looking engine. I love those long tenders too! Any RR who dispatches a loco, whose tender is longer than the engine itself, is confident in their power! Thanks for sharing all the in-process pics…Inspiring.

  10. Matt Forsyth Says:


    Thanks for dropping by, and for the kind words!! Though I am not a PRR modeler, rebuilding her was a blast, and the results speak for themselves. Not to mention the total approval and appreciation of the fellow that the work was done for (see the posted comment from her owner Pete). Everybody was a winner on this one!

    Thanks again,


  11. Matt Jackson Says:

    Outstanding detail work.

  12. Matt Forsyth Says:

    Thanks, Matt,

    And thanks for stopping by my site.


  13. Matt Forsyth Says:


    You are one of the true pioneers of present-day O Scale modeling, and such high praise coming from you means a lot. You’re extremely active, always re-inventing your own layout, and you continue to perfect your many tools and techniques. You too are an inspiration…

    I only wish that the few nay-sayers and malcontents in O would either step into the 21st Century, or get the hell out of the hobby!! Wishful thinking I guess…

    Thanks for all your support.


  14. Matt Forsyth Says:


    Thank you so much for the praise…I truly appreciate it! Indeed, it will not be all that much longer before a few more of my re-worked pieces are gracing your layout and display.