I model 1905 in HO and needed a wagontop 4-4-0. The HO, really OO scale, IHC Oldtime 4-4-0 is the right size but it has tender drive and large flanges. The new HO Athearn/Roundhouse 4-4-0 is a fine example of a 1905 4-4-0 with a motor in the loco and nice flanges. It also has sound, good electrical pickup and sound. Merging these locomotives makes a great HO 1890s 4-4-0. The addition of a straight stack and possibly a more modern cab will take the locomotive into the early twentieth century.
The Mechanism (Click Images to Enlarge)
The Tender (Click Images to Enlarge)
Drill out an remove the valve gear rivet. Cut the IHC frame along the red line even with the bottom of the boiler.
Cut out the opening in the IHC part so it will fit over the Round house mechanism. This shows a 2-8-0 mechanism. For the 4-4-0, the bottom of the running board should be even with the "firebox". Remove material to allow the mechanism to clear the screw for the valve hanger. The boiler should set on the valve hanger.
Attach lugs to the inside of the cab and tap them for an 00-90 screw and attach the top half of the boiler to the running board section with three screws.
Take the weight out of the IHC tender and bend it to fit the cab roof. Cement it in place to the inside of the cab roof.
Install the Roundhouse pilot truck screw by reaming the hole in the boiler slightly smaller than the screw and "self tapping". Relieve the hole so the screw goes in far enough.
Cut the saddle off the cylinder. Cut the remainder of the saddle off the cylinder block. Use a plastic shim to get the correct boiler placement. Glue them all together.
Mark the wires with white paint and write down where they go. The white mark on the motor indicates the bottom.
Shorten the rear of the frame. The centerline of the smokestack should align with the centerline of the cylinders.
Grind two wire slots in the back of the frame.
Drill two holes in the back of the motor recess and cut out the area with a jeweler's saw.
Smooth out the cutout so the motor slides down into the frame. Grind clearance for the motor wires. Make a light press fit motor mount from .060 styrene and press it up against the motor. Press the worm gear on the motor against the spur gear. Glue the motor mount in place.
Drill a hole to clear an 1/8 square piece in the motor mount. Use an 1/8 square x 3/32 long styrene piece with an 0-90 tap in to make a motor mounting lug. Glue the lug to the bottom of the motor. Make an .060 styrene spacer and attach the spacer to the motor mount.
Make a "washer" out of .030 styrene and shim out of paper to give clearance to the gears and mount the motor with a flathead screw.
Remove the part from the track pickup that goes thru the frame. Relieve the bottom plate and attach the track wires.
Attach the motor wires. I didn't use the wires for the light.
Reassemble the bottom plates and drill a hole slightly smaller than the drawbar screw. "Self tap" the screw into the plates and file it flush.
Make a temporary drawbar out of .030 styrene mine has a cl to cl of 1 inch.
Assemble the mechanism using one of the IHC tender truck nuts to attach the pilot truck to the frame. Test the mechanism on DC.
A Mantua pilot truck spring is the righ tension. They are available from Yardbird Trains.
Level the boiler on the mechanism using an indicator. Use an 00-90 screw to attach the rear of the mechanism to the frame.
Assemble the mechanism to the tender. Mine pulled 20 cars.
Cut the tender at the top rivet line. This will put the lower row of rivets in the center of the body.
Make two slots at the front of the tender back to the bolster for the wires.
Throw this unit away and install a Soundtraxx mini-Tsunami.
Use the lip from the IHC tender on the back to the Roundhouse body. Make a mounting lug in on back corner and a mounting screw at the front on tender deck.
Make a wood load deck and rubber cement it to the tender so the deck can be removed. Make a box to cover the capacitor and paint it black.
Use the tool box covers from the IHC tender. Assemble a wood load on the tender deck by carefully gluing wood. It should be removable. This makes an 1870's OO 4-4-0, an 1890's HO 4-4-0 needs a coal bunker, smaller stack and extended smokebox. The little guy on the running board is HO.
We will be updating this article to make the merge into an 1890's modernized to 1905 HO 4-4-0.
Unfortunately the MRC unit in these locomotives are crap. It will eventually fail so do yourself a favor and install a Soundtraxx unit.