The World of HO Open Framed Motors

Open framed motors for the majority of Brass Steamscaring on the armature which can make the motor
Locomotives and many Diesels still are in use sinceuseless.
post World War II. They were a main stay to power3. The open frame motor requires lubrication at each
the locomotive. These motors were all produced inend of the motor where the bearings are located. The
Japan except for the Pitman Motor which wasmanufacturers would place a pad around the motor
produced in the United States.shaft next to the bearings. Here is where you would
About thirty five years ago the industry beganlubricate the motor. The problem is that these pads
changing over to the Can Motor. The Can Motor waswould get old and shrink thus eliminating the lubrication
introduced in new locomotives to be sold to theprocess.
hobbyist. It wasn't until a few years later that the4. The best thing to do is tear down the motor and
hobbyist could buy the Can Motor for personal use.rebuild/replace the vital components except the
Why the sudden change to the Can Motor? Whatarmature. This can be a difficult process and very time
reason for such a major overhaul? The following is aconsuming. It doesn't mean the motor is going to run
presentation of the reasons for those changes andany better. Open frame motors when left standing for
the advantages as well.any length of time, accumulate debris and generally
The open frame motor was a nightmare to keepwon't run.
running. There were several reasons for this.The Can Motor eliminated all of these problems and is
1. The brushes and armature are exposed to thefar more sensitive to electrical input than the open
atmosphere. This allows dust particles which areframed motor. It was almost impossible running an
charged to accumulate on the armature and adhere toopen frame motor at low speeds where the Can
the brushes. This alone can cause major problemsMotor is best suited operationally.
electrically. It takes more power to turn the motor dueThe open frame motor is not really adaptable to the
to resistance and debris build up. That is it creates anew DCC operations. This is the opposite for the Can
resistance which bogs done the motor.Motor as it is suited for running of locomotives which
2. The accumulation of static charged particleshave the DCC decoders on board. The Can Motors
deposited on the two brushes becomes an inhibitor toare smaller than the open frame motors which made it
the rotation of the armature and grinds it down makingeasier for the hobbyist to install the new motor.
the motor useless. These particles also can cause