Re-motoring the Bachmann A1

 

Back in 2001-2002, Bachmann issued their first copies of the Peppercorn A1, and released them as 32-551 No. 60158 Aberdonian, and 32-552 No. 60147 North Eastern. In pretty short order, problems with the motors were identified. The motors were pitifully underpowered for this heavy locomotive:- they simply didn't have enough torque, and the engines ran hot after varying amounts of usage. Some models ran progressively slower and slower. Some models were not affected for some reason, but due to the public complaints about these locomotives and their electric motors, Bachmann decided to issue a time-limited recall. Models returned to Bachmann Europe were subsequently re-motored at Bachmann's expense. This re-call was valid only for a few months. Models returned after this period were subject to a charge. Of course, models were still subject to overheating of the boiler area and clearly this defect was not time limited !!

In any event, I purchased one (new) copy of each model long after the re-call had expired, and for a few runs, I thought I had been lucky to obtain models not affected by dodgy motors. However, my optimism was short lived, and both engines dragged themselves around the layout and on occasion - stopped altogether. Re-motoring was called for.

An initial contact with Bachmann proved promising, but, when I suggested that the defect was not time limited, like their re-call was, and perhaps they would consider supplying the motors, while I would pay postage and fit them myself, I received not so much as a courteous, "Forget it..." Even a request for service with credit card information was ignored.

In November, I happened to be assisting at The Platelayers table at the Toronto Christmas Train Show, when a young chap stopped by for a chat. He saw my re-motoring efforts on a Lima Deltic, and I then explained my challenge as regards the Bachmann re-motoring job. He suggested I should try using old re-cycled CD-Rom drive motors. He subsequently sent me one through the mail. I was surprised to discover that the CD motor was almost a perfect drop in replacement. Key word:- almost. The gear box on the A1 is integral with the motor cradle so the cradle was vital. The original Bachmann Buhler can motor is 23 mm long, and the CD motor is 26.5 mm long. The boiler at this point is quite narrow, and clearances were tight, but the CD motor had no problems fitting, width wise. The length of the cradle was the problem. I therefore seized the cradle by the horns, so to speak, and cut it in two in the middle. It was then a fairly simple matter of drilling a new hole in one side of the cradle, ensuring that the distance of the two halves, when re-attached to the frame, would be a perfect fit for the 'new' CD motor. In other words, the new hole drilled in the non-gear box end of the cradle had to be 3.5 mm away from the old one. This would allow me to still use the threaded holes in the frame. There was a raised plastic "lug" on the bottom of the one screw hole on the non-gear box end of the cradle. This had to be filed off so as to allow this non-gear box end to sit square on the frame. The mounting of the CD motor in to the cradle is very easy too, because it seems that all these small motors have a standard "shoulder" at each end of the shaft. The shoulder fits perfectly into the plastic holes on the cradle ends. It is also important to note that the shaft of the CD motor was a perfect 1.5mm so once the worm was off the old motor - I knew it would fit the CD motor.

The photos show the old Buhler motor compared to the new CD motor which has been installed. The second photo shows the gap in the cradle below the motor where the cradle was cut in two and repositioned using the same threaded holes in the frame. The result has been a very economical re-motoring of both A1s.The A1s now have no problems keeping up with the pack, and do not run hot anymore. I did not bother mounting the DCC wiring, preferring instead to simply leave it floating. While the locos were under re-construction, I took the opportunity to add weight and plasticine to the boiler.

    

This photo shows the original Buhler can motor above the CD motor

 

This photo shows the gap in the motor cradle. 

(I have readjusted the position of the worm in this photo.)

The best part was I just love re-cycling. Only older CD Rom drives have this type of motor from around the early 1990s, and not all manufacturers used this type. This type of motor may be found in Electronic Surplus stores for about $2.00

My thanks go to Bachmann for giving me the impetus to "get on with it" and fix the dodgy motors.

Gerry Taylor 2007