Micro Mark's Truck Tuner: Counterproductive?

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Ignorance is Patriotic
I have been using Micro Mark's Truck Tuner to clean out the flash from the truck bearings on my extensive HO freight car fleet. Today, I made an interesting discovery: it seems that trucks that have been cleaned with the tool roll with more friction than trucks that have not been cleaned.

To experiment, I took two identical Athearn RTR boxcars, both recently purchased, and used Micro Marks' tool on one set of trucks only, or one car. The other car I left alone. I then put two pieces of flex track parallel to each other on a glass table, and rolled the cars with my hand - hundreds of times.

There is NO DOUBT that the car I thought would perform better - the one whose trucks were cleaned with the Truck Tuner tool, rolls rougher and with more friction than the other car. That other car, in fact, rolls so much smoother and comes to a stop at a much further distance. What is going on here?

I've noticed that after being cleaned with the tool, the trucks allow the wheelsets to enjoy a much greater "side to side" movement than before, while the unmodified car doesn't allow such movement. It is the latter car, ultimately, that rolls more freely.

Am I using the tool wrong? (is that even possible?) My only assumption here would be that I am removing too much plastic from within the bearing, as I don't stop milling the truck until the tool itself rolls freely as an axle should.

Any advice or recommendations?
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Jeeze, I have had very good results from using this tool. You may be taking too much plastic off. Usually, I will turn the tool only a few times and then check with the wheels installed. If I feel any rough spot or don't have a good wheel spin, then I will do it again. For the slack in the axle to the truck, try not to spread them any more that absolutely necessary to slip in the tool. Also, and if necessary, you should be able to compress the truck enough with your fingers to go back to its original width.;) :)

grande man

Bonafied Grande Nut
I'm with Rex on this one. LGM and I have had very positive results with the tool. Are you using a fine touch to just remove the flash, or are you possibly pressing the trucks into the tool to hard?


Entrepreneurial Teen
I've never used it myself, but every time I read about the Truck Tuner it's always positive.

Removing too much material could make the operation worse, as the axle could have enough lateral motion to slide off center and the weight on one side of the truck would be distributed almost entirely on the very tip of the axle instead of across the entire point. Having too much slop might also allow the axle to twist and bind, which would increase the friction as you described.


Long Winded Old Fart
I redid over 200 freight cars & passenger cars w/my truck tuner & I got a 100% improvement. Before I use to have a lot of derailments because of tight wheelsets.
Did you know that the truck tuner only cuts one way? you have to turn it over to cut the other side. I press in toward the tuner w/a slight pressure until it feels smooth. If you press to hard it will ream out the hole & the axle will be sloppy. Look at the tuner to see the cutting side. It has the same bevel as pointed axles. Some axles are blunt & the reamer won't work on those trucks. I changed about 100 sets of trucks on some of my cars.
I don't know if this helps or hinders.
Another thing I did was use graphite powder on every axle before I put it back in the trucks.


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