# Changing wheels and axles



## flyerrich (Feb 17, 2014)

I have a Bachman small steamer 0-6-0. The tender derails a lot going through some switches. I took a lot of time trying to determine what the problem was and noticed the flanges on the tender axles is about half what other wheels are. When I look for replacements I noticed different sizes like 33" etc. how do you determine the proper size for rolling stock? I assume steel wheels perform better(?).


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## lajrmdlr (Apr 25, 2014)

Get a NMRA gauge to check the wheel spacing. Either too narrow or too wide cause derailments. Also check for wheel wobble. Wheels on plastic axles can wobble if the axle is bent. Also use the gauge to check your switches.


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## traction fan (Oct 5, 2014)

*Wheel size*



flyerrich said:


> I have a Bachman small steamer 0-6-0. The tender derails a lot going through some switches. I took a lot of time trying to determine what the problem was and noticed the flanges on the tender axles is about half what other wheels are. When I look for replacements I noticed different sizes like 33" etc. how do you determine the proper size for rolling stock? I assume steel wheels perform better(?).


flyerrich;

The 33" you see on the wheel package means that the real full sized wheel this model represents is 33" in diameter. This was a very common wheel size for freight cars. Wheels for passenger cars, and some modern larger freight cars are 36". To match the wheel from the tender, measure its diameter with a scale ruler. Then you can buy a wheel set of the same size.
Metal wheels, in general are more free rolling than plastic. However for a tender they may be essential. Many model steam engines use the tender's wheels for electrical pick up. If your Bachman 0-6-0 is the same one I have(with a slope backed tender) then it is an exception. Are the tender's original wheels plastic or metal? I would replace all the tender wheels with metal, and wire them to pick up power along with the locomotive. You can't have too much electric pick up. This would help it get through plastic frogs on some turnouts. That may not be something you want to tackle though. In any case, I recommend replacing all the tender's wheels, with new metal ones.

I don't think the derailments are caused by flange size. Deep flanges should not be needed. It's much more likely that some tender wheels are "out of gauge." This just means the wheels on one or more axles are too close to each other; or too far apart. Have you measured the wheels with an NMRA standards gauge? If you don't have one you should buy a gauge. It is an essential tool. It should be available at www.walthers.com under tools, or track. What brand of track switches(aka. turnouts) are you using?

Hope that helps;

Traction Fan :smilie_daumenpos:


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## DonR (Oct 18, 2012)

Any time you have derailing at certain locations there
could be a defect in that spot.

Put a bright light where the tender derails, run the
loco and tender as slow as it will go. Get close and
watch the tender wheels, when one LIFTS off the rail. STOP.
Back it up and repeat. If the wheel LIFTS again, you've
found a problem.

There is something at that point that is permitting the wheel
to leave the rail. It may be a misalignment of the rail, either
laterally or vertically.

Don


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## CTValleyRR (Jul 26, 2014)

I agree with traction fan -- your flanges are not the issue. Yes, metal wheels will improve operation, but not if there are other issues going on.

Check the weight of the tender -- it should be pretty close to 1 oz plus 1/2 oz per 1" of car length. If not, it may be getting pulled of the tracks by the weight of the cars on either side of it.

Check the drawbar coupling with the locomotive, and make sure it is dead level, so that it is not pushing the front end of the tender either up or down, which will cause one set of wheels to ride "light" on the rails and have a tendency to ride up and over. This can usually be fixed by putting a slight Z bend in the drawbar. Check the height of the rear coupler as well.

Make sure the drawbar has enough room to swing that the tender can follow the loco through a curve. Same for the rear coupler. If there are wires between the tender and the loco, make sure there is enough slack in them (especially on tight curves). If they ever get taut, they will pull your tender off the rails.

Finally, check the clearance under the car, especially the metal uncoupling pin on the rear coupler. Make sure nothing is hanging low enough that it hits the points or the frog in your turnouts.

Lots of things to check before you decide that the wheels are your problem (assuming they are in gauge and the axle is straight, that is). Go chase these potential problems down before you run out and buy new wheels.


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## MtRR75 (Nov 27, 2013)

CTValleyRR's list is good. One more thing to add to it.

Make sure that the tender trucks are level -- both front to back and side to side. The trucks should also be a little loose, to allow them to rock slightly from front to back and side to side. If the truck can not be made to sit level, you will have to remove it and GENTLY file the flat disk that it is attached to to make it level.


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## DavefromMD (Jul 25, 2013)

A word of warning about that Bachmann 0-6-0 tender. I went to replace the wheels with metal wheels and the only ones that will fit are Bachmann replacements. It has to do with the way the point is shaped on the axle tips. I had Intermountain metal wheel sets and the end points on the axles would not fit all the way in to the holes in the trucks. When I compared the Intermountain to the original Bachmann wheels, I could see the difference in the axle points.


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## flyerrich (Feb 17, 2014)

DonR, 
Did as you suggested and found that the turnout (Atlas) is where the wheel raises up and then allows for a derailment. It appears when the switch is thrown the moveable section of rail goes as far as it can but it is still protruding in from the inside of the rail. I looks to me that the indentation in the rail is not deep enough for the movable portion to become flush with the inside of the rail.
This happens repeatedly with this tender at this location. Don't seem to have a problem with other rolling stock or any other turnouts.


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## lajrmdlr (Apr 25, 2014)

flyerrich said:


> DonR,
> This happens repeatedly with this tender at this location. Don't seem to have a problem with other rolling stock or any other turnouts.


Have you checked the wheel spacing w/ a NMRA gauge yet?


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## wvgca (Jan 21, 2013)

"when the switch is thrown the moveable section of rail goes as far as it can but it is still protruding in from the inside of the rail" ..One possible solution to this is to light file the point end to an angle , it's easier than trying to file the recess deeper in the fixed rail ..assuming that there isn't any crud in between, or that the end of the point hasn't been accidentally bent ...


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## CTValleyRR (Jul 26, 2014)

Welcome to another episode of "Things that can go wrong with Atlas turnouts".

If you have ballasted your track, make sure there aren't any stray grains of ballast blocking the movement.

If your tender is the only vehicle that has trouble with this turnout, adding weight will probably help. That said, we need to assess the earlier assessment that it isn't the flanges. The larger flanges may in fact be allowing this car to pick the points when none of your other stuff does. 

But the true problem is the turnout, and it's best to fix it as suggested above, otherwise new acquisitions may also have trouble with it.


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## DonR (Oct 18, 2012)

Ok you Atlas turnout guys. WVGCA has one possible solution,
are there any others?

I can't help. I replaced all of my Atlas with Peco Insulfrogs.

If the layout where the suspect turnout is located can be 
adjusted, a Peco might solve the problem but keep in mind
due to size and diverting angle differences, Pecos are not a direct 
replacement for an Atlas.

Don


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## flyerrich (Feb 17, 2014)

Thanks guys I will try filing the pc. Like I said this tender has very small flanges on the wheels. I haven't added any ballast yet so I will try filing. it is also true you just can't change the wheel/axle assembly the end points are different than some other rolling stock I have.
Thanks again


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## wvgca (Jan 21, 2013)

this is an installed Atlas custom Line #6 on my layout .... the inside of the point is pretty much flush with the inside of the rail ... not 100%, but pretty close, may be some crud in between, but gives no problems ... also check if the top of the point rail is even with the top of the stock rail ..







I don't know if these points were filed as it's hard to tell after weathering ..
Normally if you have only one turnout that gives problems, it's that turnout, however, if there is only one piece of rolling stock that gives problems, it may be wheelset gauge ... 
however you may have both??


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