Rio Grande PAs Blind Wheels Causing Derailment

If the blind wheels are not in between the flanged wheels, they are going to be off the rails on a curve. Just what are the details of the derailments, such as at the points, which direction, through or diverging? Slomo video would be ideal.

Yes... I have done the same on my MTH PAs.  Some details here:

• https://ogrforum.com/topic/40004357695205047
• https://ogrforum.com/...10#48593297314370410

What I did was replace the blind wheelset and then use a spring to hold that wheelset in place in the slot.

Thanks!

- Mario

@John H - I think having the blind wheel not surrounded by a flange is causing the problem. It is the innermost wheel closest to the fuel tank on each truck. Here is a video of what is happening when hitting a switch. you can see the engine bouncing around. When taken at any type of speed there is a derailment everytime.

Looks like the blind wheel is catching on the outside of the converging rail.

Does this occur if the engine is running backwards through the switch? Is only 1 truck exhibiting this behavior? Do both blind wheel axles have the same gauge? Are the blind wheels beveled on the inside?

Do you have a sliding shoe ramp installed?

What number switch is causing the problem? 072, #5, #7.5.

@ctr posted:

Looks like the blind wheel is catching on the outside of the converging rail.

Does this occur if the engine is running backwards through the switch? Is only 1 truck exhibiting this behavior? Do both blind wheel axles have the same gauge? Are the blind wheels beveled on the inside?

Do you have a sliding shoe ramp installed?

What number switch is causing the problem? 072, #5, #7.5.

Hey @Ctr Thanks for the help.

Catching seems to happen mostly on the trailing truck in regards to the direction the engine is running. One interesting thing I have also noticed, is the flanges for this wheelset seem very deep which I think is making the problem worse. The flanges hit the switch and rock the truck making it not parallel with the track causing the blind wheel to dive below the top of the rail. I have Santa Fe PAs from an earlier run and the flanges are not as deep and we don't see this issue.

All trucks are exhibiting this behavior. We have an A-B-A setup and the trailing truck depending on the direction of each unit shows the same behavior. Occasionally the leading truck clips the rail.

I have not done a precise measurement but it does seem that the gauge for the blind wheel is the same as that with the flange.

The blind wheels are beveled on the inside.

I am not sure what a sliding shoe ramp is.

This is happening on 072 switches. We have not seen this issue with any other engines and we have a decent-sized roster.

Thanks!

I had a similar problem with some Gargraves switches.  It looks like the wheels are riding upward a little on the frog.  If you take a small piece of wood about the thickness of the popsicle stick and cut it down to the height of the rail.  Glue that to the location of the guide rail and extend it back towards the frog.  This solved the problem for me.  If it does not work, you can simply pull the newly added guide out.

Marty

I have two PAs:  Freedom train and most recent PRR from four years ago.  They operate on Gargraves track and Ross switches.  The blind wheels on the Freedom Train are at the rear of the truck, next to the fuel tank and at the rear coupler.  The locomotive operates flawlessly.  On the Pennsy engine, the blind wheels are at the front of the trucks, next to the cowl and next to the tank.  The latter de- ails half the time at several switches, of different radii.  There are thirty two turnouts on my layout.  I sent the PRR loco to Lionel, pointing out the problem and it was returned as sent with a letter stating that since I was not using Lionel track throughout my layout, they would only deal with the problem if the layout track was "all Lionel."  The latter engine is pretty much a shelf queen, a very expensive one, I might add.

@Goody posted:

I have two PAs:  Freedom train and most recent PRR from four years ago.  They operate on Gargraves track and Ross switches.  The blind wheels on the Freedom Train are at the rear of the truck, next to the fuel tank and at the rear coupler.  The locomotive operates flawlessly.  On the Pennsy engine, the blind wheels are at the front of the trucks, next to the cowl and next to the tank.  The latter de- ails half the time at several switches, of different radii.  There are thirty two turnouts on my layout.  I sent the PRR loco to Lionel, pointing out the problem and it was returned as sent with a letter stating that since I was not using Lionel track throughout my layout, they would only deal with the problem if the layout track was "all Lionel."  The latter engine is pretty much a shelf queen, a very expensive one, I might add.

That's what these engines have become, a shelf queen. That is why I was curious if there is a way to get flanged wheels in each wheelset. I feel like if there is a way to basically buy 6 wheel sets for this engine with flanges the issue would be fixed. I understand the blind wheels for trying to run on 036 but 072 should be able to handle each wheel having a flange.

Take a close look at the switch. Perhaps there’s a modification that could be made, filing the rail, etc. I don’t use atlas but I have tweaked other switches just for one engine.

I had a set of MTH PAs that had the same problem in 2-rail.    These did not have blind wheelsets, but did have a dummy axle (unpowered) in the same position.    I did not replace the wheels, I just put a shim in the slot that the dummy axle rode in so it could not slide up off the rail so easily.   They were derailing on some switches in the same way.