BLUE GOOSE 4-6-4 ATSF 3460, skirted/original and deskirted/final version

                                                  scroll down and click on pictures to enlarge

Three different short YouTube movies of the Blue Goose in original and de-skirted version, made on my layout.

Shell fits Concor Hudson 4-6-4 (top pictures).....Kato GS-4/FEF 4-8-4 chassis (bottom pictures).    

Fully skirted original version, left side view, shell has been  primed.                                                                   KIT 425

De-skirted final version, left side view, shell has been primed.                                                                 KIT 426

Fully skirted original version, right side view, shell has been primed.                                                                     KIT 425

De-skirted final version, right side view, shell has been primed.                                                                     KIT 426

Blue Goose fully skirted (as built) left side                                      Blue Goose fully skirted (as built) right side

Blue Goose de-skirted (final version) left side                                 Blue Goose de-skirted (final version) right side

without engine shells                                         Blue Goose skirted and deskirted          without added wheights

                                                                                                                                                 without engine and tender shells

Stainless steel etching.

Part of KIT 425 / 426.

Decoder and original and modified                                              Complete tender/decoder Soundtraxx Eco-21 PNEM installation

 21 pin NEM conncector                                                         sugar cube speaker, capacitor, micro connectors and lead wheights

Front truck, extra wire connection,               Trailing truck wire connection,                    Replacement motor including shims  frame shortened by 1 mm                               shortened truck end, new drawbar hook           

modified cylinders and valve gear hanger   front view modified cylinders                        adapted valve gear hanger

fully skirted (original) version                        fully skirted (original) version                       de-skirted (final) version

Shell support brackets on back of motor         Chassis support bracket inside front end

Pictures below show conversion using Kato 4-8-4 GS-4/FEF. Not described below but details available on request.


N-425 Blue Goose 4-6-4 engine 3460, engine shell, fully skirted (original) version, resin casting, all flash removed, all holes for stainless steel details drilled, primed with Mr. Surfacer 1000 but not painted (no decals), stainless steel etching.

N-426 Blue Goose 4-6-4 engine 3460, engine shell, de-skirted (final) version, resin casting, all flash removed, all holes for stainless steel details drilles, primed with Mr Surfacer 1000 but not painted (no decals), stainless steel etching.

N-411 Blue Goose 4-6-4 engine 3460 streamlined 20K tender. assembled kit: cast resin body, stainless steel etchings (not attached to the shell yet - paint first), assembled trucks, wheels (all wheel current pickup), primed with Mr. Surfacer 1000 but not painted (no decals).


The Blue Goose is the only streamlined ATSF steam engine. It is the first of the 3460 class hudsons, together with 5 other non-streamlined engines, built  by Baldwin and acquired by the ATSF in 1937. Not too long after its first runs part of the shrouding was removed: maintenance proved to be costly/cumbersome/time consuming. The engine ran with lightwheight and heavywheight consists, mainly on the eastern part of the system.  It was sold for scrap by the company in 1956.  


Already long time ago I wanted to have a realistic N scale model of the ATSF 4-6-4 Blue Goose engine number 3460. There is/was of course the Con-Cor RTR model but both engine and tender shell do not even come close to the ATSF prototype. But the chassis of that model is good (still reasonable priced available secondhand) and with some modifications makes for a reliable and good running/pulling engine. The valve gear unfortunately is quite bulky and has to be modified to fit under the new shell. The first version of the model dates from 1969, with revised models issued in 1975 and 1994.

See WWW.SPOOKSHOW.NET for a detailed description of the various production runs and their pros and cons.

It took some time to find an acceptable solution to fit the 3D designed but resin cast shell to this chassis.

I also tried/adapted the Kato FEF chassis (because the driver size matches the prototype better) but that conversion is a lot more complicated (the last pictures above show how that conversion can be done).

The Con-Cor Hudson remains the easiest and probably cheaper option.

To keep cost down I decided to use the 3D printed model as a master and make resin cast copies using Form X Mold Star silicone rubber and Smooth Cast resin and a vacuum pump/chamber. The resin has the added advantage of being quite flexible: walls are quite thin at places and a 3D printed version would be quite brittle and prone to damage.

I must admit that some layering from the Shapeways printed (Smoothest Fine Detail Plastic) master is still visible in some places. When the model is properly airbrush primed and painted that is less noticeable, certainly not from some distance.

All details (handrails, grips, levers, windows) are stainless steel etchings, applied after airbrush painting.

One word of caution: the skirted/original version needs larger radius track curves. The lateral movement of the trailing truck is limited by the skirting under the cab.



To start I exchanged the motor. This is not really necessary (usually the stock motor is OK) but my sparebox Mashima is a much better motor and fits easily. Remove the worm wheel from the old motor and slide on the shaft of the new motor - a little reaming and some CA glue will do the trick. Add a 2 mm thick styrene shim to both sides of the commutator/brush extension (see picture above). Clean (and file flat) the inside of the 2 chassis "wings" that hold the old motor. Insert the new motor and tighten the frame screw. A very small drop of CA glue will help securing the new motor but removal (if necessary later on) is still possible.

Cut/grind/file the last/back part off the trailing truck (see picture above) and drill a 1mm hole into the back. Take some 1 mm steel wire, making a 90 degree bend and insert into the new hole. Secure with a drop of CA glue when satisfied about the tender coupling distance: shorter for broad curves and longer for sharp ones.

I also soldered some black very flexible decoder wire to the top of the trailing truck frame (remove wheels and plastic sideframe first). The wire goes directly to the to the tender (see picture above). The electrical connection between both front and trailing truck to the frame is weak - hardwiring solves the problem. In my opinion the more wheels with good current pickup, the better. Certainly handy when you add a sound decoder. 

Thats also done to the front trailing truck, only this time the wire is soldered to the front lip of one of the chassis halves.

I decided to shorten the front trailing truck by 1 mm to get a prototypical axle spacing. Simply cut the frame in half with a grinding disk. Glue the to pieces together with CA glue (align the 2 frame halves on a piece of waxed/baking paper and let the glue flow into the joint. I restored electrical connection with current conducting silver paint over the joint - painted flat black when dry.

I also cleaned to surface contacting the axles inside both trucks to improve electrical contact.

Now comes the tricky part.... the frame halves just fit inside the shell but the valve gear hanger protrusions prevent the shell from sitting low enough. Using a motor tool with a grinding disk remove the top of the protrusions just till the top of the extending pin holding the grey/silver valve gear part. I did this without removing the valve gear or wheels...... a bit tricky because of the metal aparticles flying around. Direct the flow of these particles to the front of the model and take it slow to prevent heating the plastic too much.

It is also necessary to remove some material at the top of the large black valve gear hanger on both sides of the engine (more material for the fully skirted version, a bit less for the deskirted version (see pictures).

For this you have to remove both valve gear hangers from the frame. First remove the cylinder block with some gentle pulling forward towards the nose end of the engine. They should slide out with a little effort. This block is connected to the valve gear hanger assembly via 4 quite large pins. Now remove the valve gear hangers. They are attached to the chassis halves with 2 large pins. Insert a small screwdriver between hanger and frame and gently pry the hanger loose. The small black box on top of the front part of these hangers falls just inside the skirting and should touch the underside of the running board. Then the shell is at its intended location. Look at the pictures above to see what (how much) material has bo be removed. As said before: more for the skirted and less for the deskirted version. Remove a little at a time - again with the grinding disk and some small file cleanup - and put the hangers back regularly to check if the underside of the running boards touches the afore mentioned little black box.

The cylinder block has to be modified as well to fit under the new shells. For the skirted version you have to remove quite a bit from both outsides and also from the front end (see pictures above). I simply used a grinding disk to remove the material and checked regularly if the modified cylinder block would fit, but even if you take away too much thats hardly a problem. Almost the whole block is conceiled by the skirting anyway, except for a small part of the bottom/main cylinder. On the deskirted version you only have to grind a small but piece off the top of the steam chest and the top front of the cylinder block. Also here: check often if enough plastic is removed, but not too much this time because in this version almost the whole cylinder assembly is still visible.

Next job is optional. I decided to try to add even more lead wheight. The engine is quite heavy by itself but with some extra work some 1 mm lead sheet can be added. As a result the engine pulled 40 boxcars (should normally pull passenger and head end cars only of course) around my layout inlcuding a 0,5 % grade with only a slight drop in top speed.

Remove the protruding top of the plastic insert that keeps the provided lead/metal wheight separated from the chassis (to prevent a short). Remove all burrs form to the engine chassis top halves. Cut a slab of 1 mm thick lead sheet (I bought a few pounds from a local plumber years ago - cheap and useful for many engines) to fit/glue under the present wheight. Put Kapton tape on the underside to prevent a short. I also cut a slab of 1 mm lead sheet  to go over the new motor: the U shape seen in the pictures above. This might mean you have to remove some resin material from the inside of the shell to flatten the inside surface. Be VERY careful not to puncture the shell..... a little at a time and hold the shell in front of a light source to see if thin pots are appearing.

If something happens use some UV light curing CA glue to reinforce the shell.

Grind a slot in the top and the nose of the present engine wheight to recess/guide/hide the 2 wires for the front LED headlight. The top of the wires should be level with the top of the wheight and you can simply glue them in place using CA glue. The LED should be right behind the hole in the shell nose (about the middel of the frontside).

One little piece of advice: check all wheel gauges and adjust if necessary.....they are usually (too) narrow. Also be very careful when reattaching the bottom plastic cover plate for the drivers..... do not thighten the screws too much or you will split the rings at the ends of the cover plate. 


I would advise to assemble the shell and tender completely and test the model first if everything is OK. Now is the time to make adjustments. This way you will be able to line up the stainless steel bands on engine and tender (see prototype pictures). 

As supplied the shell is ready for painting. It took me a long time and many emails to determine what paint/colour to use..........

Combining all the info I received, I decided the closest/best match is Model Master DUCK EGG BLUE FS35622 for the upper part of the shell and POLLY Scale BRITISH AZURE BLUE F505262 for the lower part. The first one is still readily available, the second one is hard to find (I still have some bottles) and I am not sure what the best match to current model paints is.....The stainless steel paint I leave up to your own preference (Alclad or your favorite brand of aluminum/silver).

Airbrush the area of the stainless steel band on both engine shell and tender shell and the whole cow catcher, no masking, just the whole area (and some above and below). Then I used carefully cut strips of Tamiya masking tape to hide the stainless steel/ silver/aluminum paint: 3 mm wide for the side of the running boards and tender, 2,5 mm wide front the side near the front stairs and 1 and 1,5 mm for the bands on the cowcatcher. Next airbrush the paint on the upper part of both engine and tender shell. When dry cover the whole upper body of both engine and tender shell with masking tape. Apply the paint to the lower part.

Airbrush in thin layers and be careful the paint goes on almost "dry": this way it will never creep under the masking tape.

The tire rims on all drive wheels and front truck wheels should be bare shiny metal. Some Con-cor models come with plated tires and "shiny" front truck wheels, others come with blackened wheels. The first version is basically OK although the driver rims are a bit wide. Paint the centers of the front truck wheels black (if you paint the rims as well no problem: simply scrape it of with a sharp knife when dry. For the blackened version I used a 0,5 mm tip silver paint marker. Run the engine at a slow speed and with a steady/supported hand holding the pen still paint a silver band on the tire rim. The front truck wheels are easier to paint by hand because the rim is raised.

The stainless steel details are next. All holes are pre-drilled. There are 2 options for all handrails on the engine: you can use the wire with stanchions attached or you can apply the seperate stanchions (apply a small drop of CA glue from the inside of the shell) and insert the straight wire thereafter. If you opt for the loose stanchions, insert and glue the lower one on the side of the nose after the wire has been inserted into the long straight row of stanchions on the side of the shell/boiler. In both cases you will have to make a bend in the handrail (see pictures above).

To glue the stainless steel window trim in place: put a little CA glue ONLY on the topside (under the awning).

Use the decals from Microscale set N-60-64 (not supplied). A light airbrush spray of Dullcote protects your model.

How to attach shell to chassis

Attaching the shell to the frame was a bit of a headache. The screw location of the chassis is in the wrong place for the new shell and I do not like ugly screws in full view anyway. I came up with the following solution (see  pictures above). On the back of the new motor (can also be done on  the old motor) are 2 brackets, the underside about 1 mm below the level of the present motor shaft. These brackets are simple 2 mm styrene plate (still have to be painted black), extending to be flush with the back wall of the cab. Use UV light curing CA glue to secure. Cut a short piece of styrene bar (Evergreen 3,2 x 4) to be glued in the nose front with the same tape of glue. To position this bar removed the front truck, hold the chassis in place inside the frame and locate the bar (some glue on one side only) using tweezer and holding the bar against the protruding end of the chassis. Fixate the bar using the UV light. This way you can slide the chassis just a couple of mm back and release the front end of the chassis. The back will simply slide out. To attach the shell reverse the process. This way the shell should be at the right height and you will be able handle the model.


The inside of the tender is large enough to accommodate a sound decoder, sugar cube speaker (19 x 14 x 9 mm) and capacitor.

The sound chamber is made of 0,5 mm styrene sheet and the bottom is glued (CA glue) to the tender floor. That is a terrific soundboard. As a result the sound volume CV's should be turned down a lot. As a trial I decided to use the Soundtraxx Econami 21-PNEM decoder. Its a lot cheaper then the Tsunami Steam-2 and has almost all the main features of the latter, with very good sound and motor handling capabilities. The 21-PNEM is quite large (15,5 x 30,5 mm) but look at the pictures and with some careful measuring even 3 2-pin micro connectors and some additional lead sheet wheights (to improve electrical contact wheels/rail) can be squeezed inside the shell. The 7 wires from the engine (grey/orange for motor, red/black for left/right rail, blue/white for headlight, extra right rail from trailing truck) are guided from under the cab through a slot cut under the box on the tender shell front. The main issue was finding a inexpensive 21 pin male connector. LaisDCC from China (see AliExpress) has one for only € 3,50 or about $ 4.00. The only difficulty: the Sountraxx installation guide quotes 22 locations on their 21-pin wiring diagram (figure 19 on page 15). On the LaisDCC connector pin 8 = headlight/white, pins 9 and 10 = speaker/purple, pin 21 = track right/red, pin 20 track left/black, pin 19 = ground/yellow green, pin 18 = motor/orange, pin 17 = motor/grey, pin 15 = plus/blue.

Remove part of the connector (the 3 holes attachment part) and insulate the soldered wires with Kapton tape (see picture).