Full Version: Question On Wheel Profiles
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
I know this has been discussed before, but what are the cons of using code 55 track in regards to wheel profiles. I seem to recall that some locos and rolling stock are not compatible.
Thank you all for you assistance.
Ummm.

Didn't see this question the first time around. 35

I think that you need to look for wheels that fit the RP-25 profile.

Most modern wheel sets are made to the NMRA RP-25 profile, but older stuff may have "Pizza-Cutter" wheel flanges.

It's easy enough to change out wheel-sets on rolling stock, but locomotive wheels are more of a challenge.

What happens is that the wheel flange may be too deep and will bump along on the ties and spike heads.

and/or

The wheel flanges will lift the wheel tread up off the rails while going through turnouts and crossings because they are deeper than the flangeways.

Any time that the wheel flanges lift the wheels, you lose contact with the rails and the loco's will stall.

Also, there will be derailments through turnouts and crossings.
I'm with Goat... I didn't see this post until today. 35

In N-scale, the problem with code 55 rail is that older equipment won't go through the frogs, because the flanges are too large. Anything produced in the last 10-15 years shouldn't have a problem, but older Atlas, Minitrix, Rapido stuff will have problems.

That said, replacement trucks are available with finer flanges. Not only will they run on code 55, but they'll look much more like rail wheels and less like pizza-cutters. Wink
I know little about flanges, but...
The "dissapearing" threads syndrome is quite common here, I don't know why, but if a thread is not kept "alive" for a certain period, it just falls into the abyss where "idle" threads reside, and pop up only when someone "discovers" it, or is "bumped" back to life.... Nope
Gus, and others...

The posts "move" down as newer posts are added, and threads are built. However, if you personally have not seen the thread/post, it should appear when you look for new posts - either by clicking the "new posts" link at the top of each page, or by looking for the red icon that indicates you have not read it yet. Both methods are specific to the member in question as it is part of the cookies that are given as you navigate the site.

If neither of these are working for you, please let any one of the moderators know.

Andrew
IS the RP-25 thing just for HO, or also for N? If not, is there a comparable standard for N scale?
The original post did show up in the "New Posts", but, since I don't model in N scale, I didn't pay particular attention to it. 35 Misngth

As mentioned, the main problem with using low-profile rail in any scale is that some wheel flanges may be too deep, causing them to bottom-out through turnouts, especially at the frogs and guardrail areas, and sometimes even on the track itself, where the flanges are so deep that they hit the spike heads moulded onto the ties.

Changing out the wheels on rolling stock is fairly easy, but not so with locomotives. If you have older ones with deep flanges, though, it is possible to turn them down using a cut-off disc in a motor tool, as I did with this HO scale 2-6-0 from IHC.
[Image: 100_5533.jpg]

While the loco had no problems running on my code 83 track, I thought that the flanges looked overly deep, so I decided to "trim 'em down". I don't recall if I disassembled the loco or not: the main concern is to keep the filings from getting into the motor, drive train, and wheel bearings. I applied masking tape to the frame area, both below and above the axles, shielding the motor and gear area at the same time. The tender and lead truck were removed, then leads were clipped from a power source to the motor. I worked with the loco held upright in one hand, and the Dremel in the other. Apply power to the loco until the drivers are turning at about half speed, then, after bringing the Dremel to top speed, lightly touch the face of the cut-off disc to a wheel flange, holding it lightly in place for a few seconds. Move on to the next wheel, repeating the process, then repeat until the flanges on all wheels have been suitably reduced. This may take several applications for each wheel - do not attempt to do it in a single operation.

The reason for working for only a few seconds at a time on a wheel is to avoid overheating the tire or, if the wheel centre is plastic, to avoid melting or warping the plastic. Keeping the loco upright will help to ensure that the cutting residue will fall away from the loco rather than falling into the mechanism as it would if the loco were upside-down on your workbench. Finally, using the face of the cut-off disc allows you to abrade away the excess material of the oversize flanges, rather than cutting it - with the wheels turning, you'll get a much more regular (round) finish on the reduced flanges. The light touch ensures minimal heating of the wheel and reduces the stress on the cut-off disc - nevertheless, always wear safety glasses when using a cut-off disc and particularly when using it in this fashion. At 30,000rpm, the pieces will continue to cut if the disc should shatter. Eek

Wayne
Having done a bit more reading, there appear to be 3 standards for N-scale flanges: fine-scale, standard and hi-rail. The fine-scale flanges will run on code 55, but the hi-rail (pizza-cutter) won't. A lot of new rolling stock is coming with fine-scale wheelsets, but most will be standard or hi-rail. Those will need to have their wheelsets replaced with fine-scale, like MicroTrains low-profile wheels.

RP-25 is a recommended practice, and so isn't an industry standard. I believe the industry standard for N-scale is still the pizza-cutter hi-rail flange.
Actually the current Pizza Cutter flange is mostly a Micro-Trains thing,and it appears that with their new 33" and 36" wheels they are finally moving away from it.

A lot of the older rollingstock in N scale has oversized flanges that can be cured by swapping in aftermarket wheel sets.ATLAS,Fox Valley,and Micro Trains all make wheels with smaller flanges that are totally compatable with code 55 and some will even work on code 40 rail.
Code 80, then - I'm not inclined to change out a fleet of locos. Life is too short and I have miles to build before I sleep. Big Grin