Has anyone run cars with the wheel flanges cut down. Is this something that is worth the effort (I have a small lathe) and if so what is a good workable wheel profile?
Thanks,
John
I believe you can but honestly smaller flanges will give you more problems on switches and on less then perfect track. Unless you want your wheels to be more prototypical Its probably not worth the effort. I have a few wheels with small flanges and they are not a fan of my Aristo frogs and when my track is not even side to side.
Cutting down the flange is only part of the job, tooling the proper profile into the flange is the rest of the job. With a lathe and proper tooling you can do it without too much problem. But like Shawn said, you may have problems with the wheels after you cut down the flanges.
John Witt said:
Has anyone run cars with the wheel flanges cut down. Is this something that is worth the effort (I have a small lathe) and if so what is a good workable wheel profile?
Yes. But the caveats already mentioned apply!
If you are trying to make grossly out-of-scale wheels actually run without bumping on the rail spike heads on the track, then just taking some off the outside of the wheel flange will help.
The professionals and experienced modellers use a tool with a wheel profile to turn down the flange to the correct shape,
http://www.clag.org.uk/bill-newton1.html
http://www.cumberlandmodelengineering.com/CustomMachining.html
I decided to try one truck and run it on an Aristo D&RGW box car. It was relatively simple to take the truck apart and remove the wheelsets which were then chucked up and turned down. I cut the flanges down to 1.305 diameter which gave a .050 high flange. I then reset the tool to bevel the flanges on the rail side to approximately have the fine edge of the flange in the same position as it was in originally, this giving a steeper bevel angle than the original. The back side of the flange was then beveled to get an overall edge thickness that “looked good”. After these cuts the flange edge was filed to a smooth roll.
I reinstalled the finished wheel sets and truck onto the car and galloped out to the railroad to try it out, only to find that a white oak branch had partly dismantled one of the trestles in the overnight winds we had. After an hour or so of work, I got to run the car behind my R/C GP-38 (I know, incorrect scale and eras). It worked for most of the railroad, but derailed in the two tightest bends, the cause being that the engine has body mounted couplers and the coupler swing was dragging the car off the track. I added an intermediate car and everything was good.
The cut down flanges look nice and I’ll try adding a few more and see how they operate in longer trains. The machining operation took about 20 minutes for the two axles, a part of which was spent working out how to do it. A machining fixture to hold the wheels more firmly will speed up the sequence.
One more data point, right! Oh, to have a machine shop like Cumberland.
John
My experience has shown me that ‘fine scale’ flanges will function quite well on any track PROVIDED the truck can articulate to follow the course of the track.
Truck mounting needs to be like a three legged stool. One truck must be tight enough to not allow the car body to rock side to side, but loose enough to turn freely. The other truck must allow side to side sway of the car body on the truck bolster.
The truck itself must allow for articulation of the axles relative to the rail. If the tread of the wheel tire raises above the head of the rail, the flange will climb the rail and a derailment will result. The importance of this was the result of an issue I had with an AMS tank car I own. AMS uses a ‘fine scale’ wheel profile, which for the most part have served me well. This one tank car started derailing on one section of the club layout. After an hour or so of observing how the car and train were acting on that section of track I discovered that there was a small dip in the track. Watching the truck as it crossed this dip, the truck was stiff and did not allow the wheel to drop as the wheel rolled over that section, the flange immediately climbed the rail, and it was on the ground.
After a call to Accucraft, I received a set of the lighter (softer) springs usually used in the lighter flat cars. I replaced the original tank springs with the softer springs and went back to the layout. Assembling the same train and I began running. No derailments. Studying the area again, the truck now has enough articulation to follow the track.
After this experience, it is my belief that articulated trucks will perform better than rigid trucks, REGARDLESS OF WHEEL PROFILE. As a result I have begun a slow program to modify all my Bachmann and USAT trucks on my rolling stock to allow them to articulate.
http://freightsheds.largescalecentral.com/users/narrowgauge/test.mp4
Bob,
I absolutely agree about articulation. The railroad we are running on was built in 2004 and the track is now much rougher than as built. Most all of our rolling stock works well because of truck flexibility. The truck I modified is one of the LGB arch bar style that has four springs and removable spring planks. These are quite flexible in pitch and roll and what I call “skew” in that the side frames can pitch in the opposite directions on each side. The Aristo car I used is fairly light, but still has enough weight to allow the trucks to articulate.
Incidentally, the worst engines we have are a pair of Aristo C44-9 which have a long 3 axle truck without enough compliance and offset pivots. Even with big flanges, these engines will shove an axle set off the track at the slightest provocation. And they are NOT light.
John
Bob, John ,
Yes, springs can make a difference. I have some Aristo smooth side cars that started life as observation cars, converted to coaches.
In the process the wheel base was shortened 2 inches. They still had problems with Aristo wide switches. The stock springs
were a bit stiff, so I changed the outer springs on each side frame to a softer spring. (might have been FA replacements)
This changed the flex of the truck, and the problem was gone.
Kevin
Thanks for the advice and comments about the truck springs. I also have a few of those Accucraft Tank-on-Flat cars that derail with very little provocation. I’ll experiment with some different springs and see how that works.
Aristo used to sell softer truck springs for their streamline passenger cars, because the original springs were to stiff, and the the truck wouldn’t “Equalize”, or articulate as Yunz call it. I fixed my one stream-liner by removing 2 springs per side, as per the recommendation on George Shrayer’s website. I did order the softer springs, twice (long story), and someday I will swap out the remaining stiff springs and replace the missing ones.
But I had an LGB Mogul tender that would derail rather regularly at my upper reverse loop. Watching that tender I could see that the truck would equalize too much, and drop one wheel between the rails. That would cause a wheel on the other axle in the truck to pop up and over the rail head. So I modified that truck so it will not equalize at all and it hasn’t derailed since. Yes, since then I have rebent the outer rail to eliminate that over gauge section of track, during the next spring rehab of the railroad. Since the Mogul tender truck was the only thing that derailed there, the easiest quick fix was to stiffen that truck.