Bill,

I've done it a couple of times for customers, but it's a real pain.  I have a small milling machine and you have to mill down the rear portion of the frame to make room for a small oval speaker and enclosure.  First you have to totally disassemble the chassis so it can be securely clamped into the milling machine's x/y table.  Even with a milling machine, it takes about an hour to get it done because you can only remove a small amount of material at a time.  You also have to be careful that you don't damage the rear truck mounting area. 

A faster way to do it would be to use a bandsaw with a metal cutting blade.  Unfortunately, I don't have access to a bandsaw.  You might be able to do it with a hacksaw, but that would be tough going and again, you need to make sure you don't damage the truck mounting area as you do it.

Good luck,

Tom

For the newer style board shown in the top photo, I use what I like to call the blunt force trauma approach when installing a decoder.  That is, I cut the board apart between the screw mount hole on the left side of the photo and those large green "do hickeys."  That leaves me with the marked/identified solder pads showing the polarity of all the wiring circuits without having to worry about what component does what to what on the rest of the board.  I hardwire the decoder's power pickup and motor connections to the appropriate tabs on the remaining portion of the board.  I then make the lighting connections using resistor values more to my liking for the headlight and tender light.  This also ensures the decoder's motor control is not compromised by other components on the factory board.

This approach works extremely well for Tsunami sound installations.  Removing most of the board opens up room in the tender to install a large speaker and speaker enclosure, which provides excellent sound output.   

While this no longer makes for a plug and play decoder installation, it does remove any ambiguity of what does what on the board.

Tom

Yes, but it takes a lot of effort.  I've done it twice now for one of my DCC services customers.  It takes about 5 hours work to do it.

A Seuthe #22 smoke unit can be made to fit.  The #22 is a relatively small unit with an isulated jacket designed for use in locos with a plastic shell.  While most of the modern American shell is metal, the smoke box area is plastic.

First, you need to remove the loco cab and then the boiler from the chassis.  Next, you must remove the smoke stack.  There is a small philips screw at the bottom of the stack and to remove it simply slip a small jewels screwdriver down the stack.

Once the stack is removed, you use the screw hole as a centering hole to drill a 3/16 hole to make room for the smoke unit's stack.  I do this by holding the drill bit in by fingers and gently twisting it.  You must go slow and careful because you want to preserve the stack flange casting on the shell.

Now the fun really begins.  You now need to mill down the metal frame above the cylinder cradle by just under ¼".  You do this from the front of the casting back for ½".  You need to remove this metal to provide clearance for the smoke unit to fit within the boiler casting.  But, before you can do the milling, however, you must remove the motor mount portion of the casting from the drive wheel assembly.  To do this, de-solder the motor power leads from the motor and you remove two screws from the bottom of the wheel assembly.  You can then mount the motor assembly in a milling machine x/y table and mill out the material.  After you mill out the material, you then use a drill press to drill a 5/16" cup centered above the cylinder cradle.  You then take a #50 drill bit and drill a hole at a 45 degree angle towards the rear of the loco.  The 5/16 hole provides a cup to hold the bottom of the smoke unit and the #50 hole provides an opening to pass the smoke unit wires out.

To provide power to the smoke unit, I run a pair of wires under the locos running boards back to the cab area.  Since the units I've done are controlled by DCC.  These wires are connected to the tender with a two pin plug.  The smoke unit itself draws over 125 mA of power.  This is generally too much for a decoder function to sustain.  As such, you need to wire in a micro switch.  In doing so, you use the decoder function to control the on/off of the micro switch.  Track power is then provided by the switch to power the actual smoke unit.  You want the ability to turn the smoke unit on/off, because it will quickly self destruct if it runs out of smoke fluid and you don't turn it off.

Lastly, I make a replacement smoke stack using a spent 22 caliber long shell casing.  To do this, you must drill out the bottom of the shell.  Make sure that it is a spent/fired shell.  There is a primer charge in the shell, so simply removing the bullet and powder will not work.

Good luck,

Tom

I finally figured out the problem.  There were two small screws under the cab floor that I didn't see.  They were obscured by some of the "piping".  Once I removed them, I could "wiggle" the boiler shell up off the chassis/mechanism.

Tom

Has anyone successfully removed the boiler shell from an HO Modern American 4-4-0?  Thus far, I have removed the cab and the mounting screws hidden by it, the screw from under the cylinder cradle, the small wire pipes from the boiler to the tops of the cylinders, and the supports from the smoke box to the pilot.  The front of the boiler shows some movement, but the rear portion is not coming free.  The Bachmann Item No. is 83401.  Any thoughts or insight into what I may be missing is greatly appreciated.

Tom