An improvement for jerky running Atearn RTR locos
#1
Hello!

In my rolling stock there is an Athearn RTR SW1500 switcher which tended to run jerky and was stalling often in the last time.
Researching the problem lead to inconsistent current pick up as cause.

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Small pieces of 0.3mm bronce wire were soldered onto the metal strips in the trucks. 8 pieces in all forming direct wipers onto the wheels.

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A look from underneath.
Needless to say all stalling and jerking disappeared instantly.

Lutz
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#2
Very nicely done ! Thumbsup Thumbsup Thumbsup
I WILL have to remember this trick !!!
Dirt, corrosion, and some "insulating"lubricants, can get between the axle, and the Bronze bearing, and between the bearing, and the metal bearing supports/ contact plates. These wires bypass the axle/bearing "problem". Cheers
We always learn far more from our own mistakes, than we will ever learn from another's advice.
The greatest place to live life, is on the sharp leading edge of a learning curve.
Lead me not into temptation.....I can find it myself!
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#3
There are some more tricks:

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The red loco was one of those crap which was overstraining my nerves due to not running well. When "cold", meaning it was not in motion longer 2 hours ago, it was really jerking and stalling. You have had to "burn it in" for app. half an hour at full throttle at first. Then it runs rather well as expected from a nearly new loco.
I nicknamed it Mao's Revenge Curse
Until i solved the problem.

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If looking closer you see it is a typical Sanda Kan product. Life Like P2K, Atlas, Athearn Genesis and here in this case Brawa use the same kind of truck construction. An enclosed gearbox with split axle wheelsets with blunt axle ends. Inside of the truck side frames, there are brass strips with small axle bearing cups pressed in. And through this blunt axle ends and the little cups the electrical current have to flow to the loco.
Some times the electrical current does'nt flow properly and the loco stalls.
In short terms Mao's Revenge got 4 direct wipers. Made out of 0.5mm brass wire bent to somewhat Z-shaped. Four 0.5mm bores were drilled into the truck crossmembers and the wipers are thus enabled to take some cantilever action and wipe the wheels with a constant tension.

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A closer look. The connecting wires from the main board were soldered direct onto the wipers. Thus bypassing the axle bearings and eliminating current pick up problems. Also i have turned down the deep German flanges to civilized (NMRA) depths.
Mao's Revenge now operates reliable, even with DCC.

If any other P2K, Atlas, Athearn Genesis or similar stuff in my loco stock is starting to make trouble in this manner, it will get the same treatment.

Lutz
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#4
Nice fix. Thumbsup
 My other car is a locomotive, ARHS restoration crew  
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