Compatability of a Bachmann Trolly Body Shell with Another Motor Chassis

[troopamg]

What I have are four Bachmann Trolley body shells.  I have read about another member that was able to take a motorized chassie (I do not remember the type)and he made the bachmann shell fit it by adding a few spacers to fill in the difference in width.  I wish I could find that posting because I want to do the same thing. Has anyone ever attempted to do the same.  Much obliged.

[troopamg]

Thank you.

 

[brill27mcb]

If you have not seen my webpage of chassis dimensions, it may help you find a suitable chassis:

http://www.trainweb.org/tomix/chassis_dim.htm

 

Are you talking about the N-gauge Bachmann Brill or the PCC? For the Brill, a Kato "bogie" (double truck) chassis (11-105, 11-106 or 11-107) could be used but has a slightly shorter distance between the bogies than the original Bachmann chassis, and the bogies are slightly smaller, too. The Tomytec TM-TR01 is another candidate, with a similar "slightly smaller" situation. For the Bachmann PCC, you might use the Tomytec TM-TR04, which is like the TM-TR01 but longer.

 

I personally have never considered a chassis swap for these Bachmann shells because they were poorly and inaccurately scaled in order to accommodate their large motor back in their day. But other people don't mind that issue, so it's up to you. If I recall right, there was someone on Shapeways who offered a 3D-printed chassis adapter, but since Shapeways and its Marketplace went belly-up, that is no longer an option.

 

Rich K.

[troopamg]

The body shells are indeed the PCC Bachmann models.  But I think I will  also need something for a spacer to fill in the difference in width to hold it in..  I guess I am on the road to experimentation.  I am just not satified with the Bachmann motor chassie.  Thanks ffor the info.

[brill27mcb]

See this thread on "The Railwire" forum on repowering a Bachmann PCC with a Tomytec TM-TR04 chassis, including how the body was mounted to the chassis:

https://www.therailwire.net/forum/index.php?topic=57336.0

 

You will have to go down about 30 messages before it gets germaine to your interests. I forget if you have to sign up on that forum in order to see the photos.

 

Rich K.

Edited January 15 by brill27mcb

[troopamg]

The article from The Railwire was great.  I have the shell and waiting for a TR04 to arrive.  I would like to see more detail on mounting the chassie to the shell like more photos of the 3m doublesided tape being applied and attaching the plastic stirene.  But thanks for all the info.

[troopamg]

Well the TR04 has arrived and so I tried thr first step.  Extending the chassie.  You first remove the screw on top.  Then you remove the two prong round plug on top so you can extend the chassie (which detent is the 46.4 position) then tighten it down.  Am I ok so far.?

[brill27mcb]

There is no need to remove a screw. You lift out the round plastic plug and the push the movable part of the chassis back and forth. It takes a little effort, because it clicks into the three wheelbase positions. Then replace the plug so that both prongs go into something, and you're done.

 

Rich K.

[troopamg]

That round plug is hard to come out.  Is it supposed to lift up and out?  I wish someone could post a video of these steps as still pictures don't always show howto do it.

[cteno4]

 YouTube is your friend.

[brill27mcb]

This video proves that anyone, no matter the level of skill and thoughtfulness, can motorize a Tomytec tram. It shouldn't even take 26 minutes...

 

The best way to do this is to carefully remove the dummy chassis from the bodyshell and adjust the wheelbase of the motorized chassis to match it. Then you either 1) move the bogie sideframes from the dummy chassis bogies over to the motorized chassis bogies, or 2) use the correct sideframes that come supplied with the motorized chassis, whichever way the parts come for a particular model. Make sure the sideframes stay right-side-up. Then place the two chassis side-by-side to determine which end chassis extensions are needed (instead of guessing) to make the motorized chassis the same length as the dummy one.

 

You can use a small flat blade screwdriver or hobby knife to pry up the thumbtack-like retaining clip. I use a small amount of tacky glue (PVA?) to hold the end guard pieces to the ends of the chassis, and to secure any provided small metal weights into the cavities of the chassis extension pieces. If needed, you can also secure the extension pieces themselves to the chassis ends with a little tacky glue. After the glue sets in 10 minutes or so, then carefully pop the chassis into the bodyshell, making sure it's in at the right height and level, and that all the little pieces are still where they should be. You are then ready to run.

 

Rich K.

[troopamg]

On 1/15/2025 at 4:28 PM, brill27mcb said:

See this thread on "The Railwire" forum on repowering a Bachmann PCC with a Tomytec TM-TR04 chassis, including how the body was mounted to the chassis:

https://www.therailwire.net/forum/index.php?topic=57336.0

 

You will have to go down about 30 messages before it gets germaine to your interests. I forget if you have to sign up on that forum in order to see the photos.

 

Rich K.

 

[troopamg]

Ok, I have watched the video.  I have lifted off the little round button and extended the chassie to the middle detent and replaced the button.  I have added the four bolsters.

Now comes my first problem.  While pressing on the bolsters, the rear sub assembly fell out with a small round part falling off.  How does it go back on?

[troopamg]

Forget this post, I figured out how it goes back.

[troopamg]

I have another question.  I just got a Two Car Tram.  Question is, How do you get it to go slow?  You put it on the track and turn of the transformer and it takes off like a rocket.  Could it be the tranformer.  It is a N/Ho transformer

[cteno4]

What is the brand and age of the controller? Some old rheostat controllers can be jumpy with their power output.

 

Are you turning the throttle slowly?

 

Have you run the mech for like a 15-30min run on a loop to break it in? This process sort of gets the lubrication all moved around and parts sort of meshed up better and they tend to start easier and run smoother then.
 

The smaller Tomytec mechs tend to get going at lower voltages. Could try making a little pwm power supply that would give finer control on speeds.

 

jeff

[troopamg]

2 hours ago, cteno4 said:

What is the brand and age of the controller? Some old rheostat controllers can be jumpy with their power output.

 

Are you turning the throttle slowly?

 

Have you run the mech for like a 15-30min run on a loop to break it in? This process sort of gets the lubrication all moved around and parts sort of meshed up better and they tend to start easier and run smoother then.
 

The smaller Tomytec mechs tend to get going at lower voltages. Could try making a little pwm power supply that would give finer control on speeds.

 

jeff

What is a pwm power supply.  Yes I turn the throttle as slow as possible.  I will run it continually. for a while to see what it does. and have to check the brand of the controller.  

Thanks.

[cteno4]

Pwm stands for pulse wave modulation and it runs the motor by pulsing the current at different frequencies and duty cycles to get motors to turn over at slower speeds with little kicks so it doesn’t just take off. Use to be called “pulse power” way back.
 

If it’s sort of all or nothing it could be the controller or it could be something binding in the drive chain that is restricting movement of the drive chain at lower voltages. With the adjustable carriage and fiddling with it something may be a bit out of alignment and getting some resistance.

 

jeff

[troopamg]

I have one other question and it pertains to the Tomytec motorized bus chassie.  How do you make it go faster?  It has a new Energizer #357 battery.

 

[cteno4]

Some of the newer models had the 2 speed option that was triggered with a magnet. I think the most recent round dropped that feature. Otherwise the single speed busses are just one speed. Newer battery may juice it up a tiny bit but not much.

 

jeff

[brill27mcb]

It was the original, older BM-01 through BM-03 chassis that took two batteries and had some sophisticated features like the 2-speed chassis. The BM-04 is a simplified design without these features, and it takes only one battery. So the speed is the speed, and you really don't want it going unrealistically fast. They just trundle along...

 

According to the internet (so it must be true):

"Energizer 357 batteries are not the same as LR44 batteries, but they are comparable and can sometimes be used interchangeably. 

LR44 - Voltage 1.5 V, Alkaline, used for small electronics like watches and calculators.

357 - Voltage 1.55 V, Silver oxide, used for precision devices like watches and medical equipment"

 

Rich K.