Disassembling an On30 Bachmann Porter

On30man's Homepage exploded drawing

How to Disassemble a Bachmann On30 Porter
by Ted Hawkins

The Bachmann Porter is an out of the box ready to run On30 locomotive. It's not meant to be taken apart or customized. However this is On30 and most people who model this scale like to mess around with things. If you want to do that with this little loco - it's not as easy as you'd think.

To do a decent job on detailing and painting, this loco needs to be broken down into manageable elements. I decided to get rid of the lights. If you want to keep the lights, then some of the procedures will not apply to you.

Re-assembly is in the reverse to dis-assembly. If it helps, make notes.

Step 1 - Get ready
With the loco comes an exploded drawing. It's fairly accurate. Read over it carefully and look closely at the model. Spend some time doing this so you are familiar with it. Do not attempt to do anything yet.

Step 2 - Small parts removal
Get a small box for the parts or a decent size sheet of paper. You can either sling the bits in the box or lay them out on the paper like the exploded drawing. Nearly all the parts are press fittings, some with catches in slots. The first thing to do is gently remove the following items - use some tweezers and take your time:

The whistle from the cab roof (be careful it is not brass)
The sand pipes
The sand lever bar which goes from the dome into the cab
The cab windows - press out
I could not get the bell out so left it for the moment (impossible)
The headlamp - simply unscrew the tiny screw

Some of these bits are easy to pull out and some aren't. It all depends on who put the loco together in the factory. Don't be surprised if a few of these are glued in. If they are you'll just have to do the best you can. When you have the engine to the stage like on the right you're ready for the next part.

Step 3 - The cab, tank and smoke stack
If you are not going to keep the lights you can cut the red wires* to the headlamp and remove it. Otherwise leave it there.

* Make sure the red wires do not short out on the boiler. Cut one of them short inside the opening.

Gently pry the spark arrestor lid from it's body on the top of the smokestack. With a fine Phillips head screwdriver remove the screw down inside the stack. Twist and pull the stack and it should come off.

The saddle tank is held by 4 screws on the underside of the tank. Turn loco upside down and use a fine phillips head screwdriver (with long enough shank to reach them) and unscrew all 4 screws. The tank should then lift off the boiler.

Removing the cab could end up a mess. It is actually glued to the deck. The glue seems to just be plain old styrene cement layed along the join on the inside. I found that the deck flexed a little as I gently pried the cab upward from the rear. This caused a separation from the cement. Do it very slowly using a thin (but rigid) blade of some sort. Try not to damage the deck or the base of the cab.

The steam dome is a press fit and can be removed easily. The throttle bar is extremely tight!

Step 4 - The motor and boiler

Things start getting tougher at this part. By tougher I mean more strength is needed and a lot more care. The motor is "snapped" into the gearbox. This is at 2 points. Look at the exploded drawing, follow the line from the motor to the gear box section. See the curvy bits of the box on either side of the line? Those are the points where the motor snaps in.

First - unsolder the black wire from the motor. There are no other wires on this motor.

To pry the motor from it's position is not as easy as it sounds. I recommend a jewelers screwdriver or similar with a thin but strong shank. Not too thin though because you will need to use this as a lever.

Take a good look at the motor and worm-gear. Insert the lever at the front of the worm gear. It has a small recess (hopefully, on yours) where the motor shaft does not reach the end of the worm. Placing the tip of your lever in there and using the boiler as a fulcrum, very gently pry the worm gear upward until it is free of the 'snap'.

Then grasping the motor in the fingers of one hand, and using the other to hold the rest of the chassis, wiggle and pry the motor from the rear 'snap'. Warning! Loosing the motor from the rear 'snap' will not happen gently, it will "snap" out in a rush. - so be careful and don't drop anything (like I did). The motor should now be free and can be placed somewhere safe.

The boiler has 2 square holes near the rear (the photo shows one inside the circle). Inside that hole is a hook shaped piece of the chassis. Hold the boiler between your thumb and finger with just enough room to insert a smallish screwdriver blade into the hole and push back the 'hook'. At the same time kind of squeeze and push your thumb and finger so that it lifts the boiler a little.

Keep your grip there, insert the blade into the hole on the other side and push in it's 'hook', the rear of the boiler should lift free of it's 'hooks'. The front of the boiler is almost a press fit and should lift clear (wiggle it a little if needed).

The boiler can be placed on one side now.

Step 5 - Taking the cab deck off

With the superstructure and motor removed you should end up with this. The only thing remaining is to remove the deck of the cab. It's much easier than some of the other stuff we've done so you can relax a bit.

The deck slides (kind of) backward out of slots in the chassis. However if you look closely at the photo below you will see, inside the yellow circle, 2 little bumps. They are semi-circles which fit into a notch on the chassis. To slide the deck out requires a bit of wiggling and wrangling.

I found that if I placed the tip of my thumb into the rectangular hole left by the boiler I could sort of rotate the thumb forward and it acted like a lever. A finger underneath helped, and the deck slid out pretty as you please.

You model is now ready to paint and detail. Putting it back together is the reverse of how you took it apart.

While it's apart and after your painting etc., make sure you lube it up as instructed. Bachmann have seen fit to make this part of the warranty - no oil, no warranty. And just to make sure you lose that warranty they have not told you how to take the loco apart to lubricate the necessary parts. At the moment I am not considering doing anything to the basic chassis/gear-box. Looking at the drawing informs me that there are all kinds of very tiny bits and pieces relating to electrical pick-ups and the like inside there.

The Pilot/cylinder assembly and valve gear
I have not removed the pilot/cylinder assembly - Why?.

Because: The valve gear disintegrates big time.
Plus, the screws in the wheels (at least on my model) were not put in properly in the first place and really need re-threading so they are square.
And ---- it is a major hassle to get it all back. When you paint, just do it with great care and paint around the valve gear and side rods.

Step 6 - The wheel cover plate
To add grease to the gears the wheel cover plate is best removed. BE WARNED - this flies off at an alarming rate. The cover can be removed from either end. I used a small screwdriver and just pried the cover off from one end. It flew several feet across the room! To prevent that happening, place your forefinger on the top of the box in front of the gear tower and your thumb over the center of the cover plate. Pry it up slowly so your thumb holds the cover on. I found it easiest doing it from the rear of the cover.

Notice the wheels and the little contact pins (don't ask how long these will last) behind each inner flange. If your wheels slip off you will have to put them back and that will take some fiddling around (and you wishing you had 3 hands). When you get one pin on a flange, push the wheel in a bit and slip the other side's pin in by pushing it gently with the blade of a small screw driver until it slips behind the flange.

Putting the cover back on needs to be done by setting the gear end first, then snapping the sloping end onto it's catch. I found if I did it the other way the gear got caught somehwere and the wheels did not turn. The chassis is, by far, the most user unfriendly part of this loco. It is also the main reason that the last thing I'm gonna do is open that gearbox. Stuff pops and flies about too much from this locomotive. After all, this engine from Bachmann was not designed to be tampered with - and we've done a lot of that in this article.