Kato's idea of delivering power from the locomotive wheels to the locomotive frame through a pointed axle and socket wiper system changed the way N scale locomotives perform. The performance of locomotives with these low friction trucks has raised the bar for the competition and given the N scale consumer a high quality product.

FRICTION: a Locomotives Worst Enemy

If a mechanism has too much friction slow speed operation is just about impossible. The motor needs more power to start the locomotive rolling and when it finally does break free of the hold that friction has on it you have that classic jackrabbit start.

The first locomotive I had was a Life like SD45 built by Minitrix I believe. I eventually purchased two more identical units only with the Model Power name. These locomotives had 12 wheel pick up and 4 wheel drive. The four driving wheels were in the rear truck. Two of the drive wheels had traction tires giving the locomotives that eye blurring wobble. The pick up wipers picked up power by rubbing on the back of the wheels. This caused some excess friction, enough to make the front truck wheels skid at times. I also had a Model power GP40 with a similar mechanism. All of these models had similar power pick up problems. I changed the wheels with traction tires to solid metal wheels, this helped with the power pick up problem but two or three cars was about all the engines could pull. I tried to relieve some of the pressure the wipers put on the back of the wheels only to suffer more loss of contact problems. Eventually these locomotives all met the same fate, all that friction eventually over heated the motors. The bearings would get hot enough to melt the plastic ends of the motor causing the armiture to be off center. Now the motor can really get hot, hot enough to distort the locomotive shell. Eventually one locomotive became a dummy, one received a 1.5v motor out of a child's Stomper truck with a box car attached for the battery, and two received Kato GM5 motors. The locomotive with the 1.5v motor ran the best because there weren't any wipers causing friction. But since the locomotive had no speed adjustment, and no forward reverse control, and because stopping it usually meant a derailment it was short lived. The locomotives have a 13.5 to 1 gear ratio so the addition of the fast Kato motors made them better dragsters than locomotives. The Life Like GP38 motor would have been a better choice.

High Gear Ratios: How Fast Will it Go?

Soon this same mechanism was improved by powering both trucks like the model power RSD15. This gave the locomotive more tractive effort and eliminated the skidding wheels. But they still had the same friction problem and the same 13.5 to 1 gear ratio. Life Like started making its own locomotives using the same 13.5 to 1 gear ratio but with a much slower and more powerful 5 pole motor. Both trucks were powered and shell detail was improved. These Life Like locomotives include the GP38, F7, F40. Bachman had a mechanism with both trucks powered and had an even lower gear ratio of 15 to 1. The Bachman mechanism had brass gears and lots of friction in the trucks from the power pick up system and how the axles rode. Bachman soon totally redesigned it's mechanism making the first split frame locomotive. About the only thing about the mechanism that didn’t change was the 15 to 1 gear ratio. Atlas had a mechanism built in Austria for it's original GP30 and GP9. The mechanism was the best for its time because of its 18 to 1 gear ratio but it still had the same old back of the wheels wiper system causing excess friction. The friction combined with an under sized motor left room for improvement. I was able to improve the performance of one of these GP30s by installing the Kato GM5 motor in it. Once again the Life Like motor would have been a better choice because of its slow speed.

Weight: The heavier the Better

The new split frame Bachman mechanism had plenty of heft and traction tires making it an amazing puller. The improved trucks and wiper system had much less friction than the old mechanism. With a little tune up the trucks could be made to role even freer. You could replace the traction tire wheels with metal ones for improved electrical pickup and still have plenty of pulling power. The motor was a small three pole, but it had good slow speed characteristics. These mechanisms include the New F9, GP40. They also include the GP50, U36B E60CP, SD40-2 with the blinking light and DD40. Life Like also was able to make a heavier locomotive with lead weights especially with the wide bodies of the F7 and F40. This combined with their super slow and powerful motor made them excellent pullers. The big advantage of heavy locomotives is the added weight helps the wheels make better contact with the rails improving electrical pickup. Another advantage to heavy locomotives is the extra weight improves the coast ability. It's like stopping a car compared to stopping a loaded semi.

Motors: Bigger is better.

The Life Like motor is quite a bit longer than the motor found in the Bachman, Model Power, and Atlas Austrian built models previously described. The Life like Motor has five armatures or poles rather than three and delivers an incredible amount of torque. The motors slow speed characteristics make it perfect for most motor swaps. Most of Life Like's locomotives use the same basic motor, even the new ones with flywheels.

Flywheels: Keep you going.

Flywheels have been around for years in other scales but they are relatively new to N scale. The idea behind putting flywheels in locomotives is to give the locomotive coast when it looses power. This coasting ability gives smother starts and stops and keeps the engine going when it looses contact until it can regain contact. Flywheels work off of centrifugal force so the faster the motor turns the better they work.

How to build the perfect N scale diesel.

All of the topics addressed above factor in to the how a locomotive performs. The Kato SD40 and Kato Built Atlas SD7 were the first pointed axle low friction mechanisms. Both of these locomotives have a gear ratio of 20.26666 to 1 (pretty low). Every Atlas and Kato locomotive since has had the same or very close to the same gear ratio. One exception is the Kato U30C with a gear ration of 17.8824 to 1This low gear ratio allowed the two manufacturers to use a higher speed motor. The motors used are of a larger size than that of the typical N scale locomotive. The higher speeds of the motor allow the flywheels to create more centrifugal force giving the locomotive more coast ability. The two heavy halves of the metal frames help tractive effort, electrical pickup, and give it more coast. Life Like took the gear ratio one step further with 25.7143 to 1 in it's SW9/1200. Now Life Like is using the pointed axles in it's new GP20s for even less friction.

So what happens when you take just one of these factors out? Bachman came out with the Bachman Spectrum and Plus series of locomotives. They all had Flywheels, five pole motors, low gear ratios, and plenty of weight, but they didn’t run very well. The Spectrum SD40-2 had a gear ratio of 18 to 1, which was a big improvement over its previous 15 to 1 ratio. Unfortunately because of the added friction the old 15 to 1 mechanism was far superior. This excess friction also meant, when you hit dirty track it was as if you had hit a wall, even with flywheels. The motor looked exactly the same as the old three pole except now it was a small five pole. Life Like put fly wheels in it's locomotives but the first locomotives weren't all that great. The E units were very heavy locomotives and had huge flywheels which helped it to over come the excess friction, but the SD7s which have very similar mechanism could not. The SD7 didn’t have room inside the hood for the big flywheels and the extra weight so the friction bogged it down.

I must admit that I was very hesitant to buy Atlas and Kato because of the price. I had quite a collection of Bachman locomotives that I had tuned up and had running very well, but I was still looking for a way to re gear them. One day a man told me to stop wasting my time on junk, nothing can run with the Kato units. So one day I sent away for a pair of the Last few, first run, Kato SD45s just to see if all I had heard about the Kato units was true. After running these units a few days I was hooked. I soon began looking for an undecorated Atlas Kato GP30. All I found was a Conrail unit, but since it had black handrails and trucks I sent for it. I couldn't find any more within my price range so I ordered the parts from Atlas and built 3 more GP30s and 2 GP35s. All of these Atlas Kato units performed great but I did notice that the low gearing was no match for the high speed motor, I only used the bottom half of the throttle because they ran to fast. I began thinking that maybe the Life Like motor would be a better motor. I wanted an SD9 for hump duty. Since this locomotive needs to be able to move slowly all of the time and it will never be run with any other locomotives I decided it would be a perfect candidate. I ordered all the parts for the SD9 from Atlas, except the motor and flywheels, at the time the motor and flywheels were no longer available. I removed all of the frame material that I could and replaced it with lead for added weight. I trimmed the Atlas Motor saddle to except the Life Like motor with Northwest Short Line flywheels. I then used Northwest Short Line universal joints to connect to the drive shafts. When I was finished I had a locomotive that was as heavy as the Kato SD45 and wouldn't run over 70 scale miles per hour. It started running before any other locomotive and I was amazed at the slow speed control. I'm very pleased with how it operates.

Today Life Like is producing locomotives with the Kato design. The GP20 has pointed axles for low friction trucks, heavy split frame, low gear ratio, and I'm guessing my favorite low speed motor with flywheels. If it's all that I think it is it should run as well as my SD9. I don't model a railroad that used GP20s but I would sure like to take one for a spin. I'd even enjoy dissecting it more.

I came across a thread on the Atlas Forum that discussed similarities between the Life Like GP20 and Atlas mechanisms. The thread turned into how you could install the Atlas trucks into the life like mechanism to improve performance. It seemed like a good excuse to tear down my GP20. Here are my findings upon tearing down the Atlas GP9 and Life Like GP20 as posted on the Atlas Forum.

I was looking for a good switching GP9. I bought a Life Like GP20 because it ran at closer to scale speed than Atlas and Kato mechanisms. I planned to put my Atlas GP9 shell on the mechanism. Since it is said that the Atlas trucks will fit the Life Like mechanism I had to see if the Life Like trucks would fit the Atlas mechanism. I knew the Life Like trucks had a lower gear ratio than the Atlas trucks so I thought that this would be easier than a shell swap. The shell swap did require some filing of the Life Like frame. The Life Like trucks fit sloppy and created excess gear noise so I installed the Atlas trucks into the Life Like mechanism as described in this thread. The Atlas trucks fit tight and caused the engine to bog down on corners. To correct this I had to loosen the screws that hold the frame halves together. After swapping the trucks around I didn't notice and speed changes. All Atlas and Kato pointed axle locomotives have a 20.2666 to 1 gear ratio and the Life Like GP20 has a 21.7143 to 1 gear ratio. The difference in gear ratios is abut 5% therefore if an Atlas locomotive was doing 100 m.p.h. the Life Like should be doing 95 m.p.h. That is not a noticeable difference. In fact the Life Like GP20 runs about 50% slower than the Atlas mechanisms. The Life Like and Atlas mechanisms may look similar if not the same, but the motors perform very differently. I swapped the motors and drive line assemblies between the two locomotives. It is important to change the drive line assemblies because the Life Like motor is shorter from the end of one flywheel to the other and the drive lines are slightly longer. If you put the Atlas motor in the Life Like mechanism with the Life Like drive lines it will bind. I found that the Atlas GP9 mechanism with the Life Like motor ran nearly identical to the un-modified Life Like GP20 and the GP20 would now run with my stock Atlas Geeps. This was no surprise since Life Like has always been known for their slow speed motors. Upon closer examination of the two motors I did notice that the Life Like armatures were slightly narrower and they had fewer windings. Now that I have the Life Like motor in the Atlas GP9 there is no need for a shell swap and I am very pleased with how it runs.

In this thread some have compared older Life Like locomotives to Atlas and Kato locomotives. All I can say is that Life Like has made improvements that the hobbyist has asked for such as closer to scale speed. If you haven't taken the new GP20 for a test drive then you don't know the new Life Like. Maybe Life Like will build those Tunnel Motors.