LOCODOC BELL ARMATURE (CORELESS) MOTORS:
THESE MOTORS ARE SO EXPENSIVE THEY ARE SOLD DIRECT ONLY AND NOT TO DEALERS
Bell armature motors (also known as micro motors or coreless motors) are
a precision instrument motor that in many locomotives will offer the
very best performance possible. They are built completely differently than
can motors and have some different advantages and disadvantages.
The armature of a bell armature motor looks like an empty can with one end cut out and a shaft driven through the center of the other end. The walls of the can are laminations of electrical wires lacquered together and attached to the bottom of the can and shaft. This armature rotates inside the motor case and around an internal magnet with the shaft turning in bearings in the center of the magnet. The difference is that since there is no iron in the armature, if you loose electrical power the motor freewheels and does not brake to a stop like can motors. The light weight armature produces virtually no vibration, the gold comutator and silver brushes provide almost silent operation and the low current draw of these very efficient motors reduces wheel pitting. Since the armature has very little mass it will have very little inertia to overcome small binds and a light bulb will act as a dynamic brake. A flywheel adds the necessary inertia and I order most FAULHABER motors with double shafts to facilitate adding a flywheel to the back of the motor.
In years past Faulhaber motors were usually mated to speed reducing gearheads for 1 - 10 MPH 2-8-0s in HOn3 but the recent availability of slower and more powerful motors in the small sizes makes direct drive gearing an attractive option instead of gearheads. Bell armature motors tend to be more powerful than comperable size can motors and are available in slower speeds which sometimes match better to available gear ratios.
THESE MOTORS SHOULD NEVER BE RUN AT ABOVE THEIR RATED VOLTAGE.
The motor designation includes the metric size of the motor and the 12 volt speed as this is critical in determining what motor to use to get the speed range you want.
|Price $||79.95||79.95||94.95||84.95||84.95||149.95 BB||89.95||124.95 BB|
EXAMPLE; 1319T7.4K 1319 is the metric
diameter and length, 7.4K is the speed of 7400 RPMs at 12 volts.
All double shaft motors have 1.5mm x 10 mm shafts out each end. The 15 and 16mm. motors should never have oil put on the brush end shaft as there is no bearing here, only the comutator.
The 1331 motor is available only as single ended.
The 1727C ( BB ) motor comes with ball bearings at both ends and has 2mm shafts and carbon brushes for high current draw and longer life.
The 2020T has a built in 3.45/1 gearhead and will make a mild gear whine noise. 16/1 and 59/1 gear reductions are also available.
The 2342C ( BB ) motor comes with ball bearings at both ends and has 2mm shaft at the front and a short 3mm x 3mm. shaft out the back. Great for On3 repowers.
Until now there were no high quality motors with enough power and sufficient speed to match big steam locomotives with high gear reductions such as the PFM SF 2-10-4 and 4-8-4, the UP FEF-1, the WS SP GS-8 and the HM RI 4-8-4 and most newer Tenshodo models. I have recently obtained some Swiss made Maxon motors that are a 1640 double ended motor with a 14,000 rpm 12volt speed. They are long but the small diameter allows them to be positioned foreward in the boiler and still leave room for a large flywheel on the back of the motor. I call these the Maxon 1640T14K and they sell for $79.95. I have had large diameter Flywheels made to match their 1.5mm shafts.
Namiki motors were a Japanese made version of a bell armature "coreless" motor. The 1220 (9500 rpm) and 1230 (7000 rpm) versions were particulasrly well suited to HOn3 where the small size and low speed made much better running locvomotives than other available motors of the time.
The 1220 was used in several of the small PFM HO and HOn3 shays such as the Herrington, MichCal#2 and others where the motor was concealed in the tender and the drive to the cylinders was under the cab deck. It was also used in the first run Key C-18 #318 and the C-19 #346 where it was just barely powerful enough.
The 1230 was a much more powerful motor and was used with great successs in the Westside/PSC HOn3 C&S #74/75 2-8-0s and the D&RGW "High Grade" C-16 with cab interior and motor in the boiler. This drive was copied in the Key C&S #71 and RGS #42 C-17 and Nakamura West Side Lumber Co. shays (some with gearheads). Westside also used this motor in larger locomotives (where it was too small) like the HO Ma & Pa 0-6-0s, PRR D-16sb 4-4-0, the SP T-1 and "Fire Train" 4-6-0s and the HOn3 "Craftsman" K-36 and K-28 2-8-2s where they ran great but wouldn't pull a full train up a hill.
MOTOR FAILURES. Unfortunately many of these motors were assembled with an inappropriate grease that hardened with age. Some motors are completely frozen and others take a high voltage to start and may squeal when run. This motor should turn extremely freely at 1 volt DC, if at 2 volts it turns slowly like it is running in molases STOP NOW. Any of these symptoms will cause early failure of this precision motor. In 2007 a dealer obtained the Namiki 1220 motors Westside had originally imported for the S&S Limited NPC "Cab Foreward" HOn3 4-4-0 project and has been selling them on Ebay. Unfortunately all I have seen have the hard grease problem and need rebuilding before they are damaged. I got 12 of these motors from Westside before he did and all have been degreased.
REPAIRS; I have developed the tools, holders and techniques to repair these motors. If you have problems Email me for advise in your specific case. I also have fully reconditioned and guaranteed motors for sale
I can usually rebuild your motor for $30 plus shipping if it has not been damaged already, the reason to stop running as soon as you notice poor running.
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