Large Scale Central

Three axles vs two

Modeling Rolling stock
#1

Gentlemen,

I am running on the new indoor layout now as I continue to work on scenery and such. I have quite a few heavyweights most of which came with three axle trucks. I acquired an older Blue Comet set that came with two axle trucks. They go around the layout much easier.

I pulled the middle axle from the 3 axle trucks and that helped some but not enough. I had three BB axles so replaced one axle on three of the four trucks on two cars as a test. Made a big difference.

I have a couple options then it seems. I can replace all the wheelsets with BB and remove the middle on the 3 axle or replace all the 3 axle with two axle trucks.

Any recommendations from the crew here? Anyone have two axle trucks for heavyweights they would like to trade for three axle trucks?

Andre’

#2

Andre,
Looks like you’ve basically got it figgered out.
BB would be the way to go.
If you want to keep the three axles sets for looks, you can always “blind” the middle wheel by grinding off the flange. But that’s a chore unless you have a lathe or some such tool to do it with.
jb

#3

John,

I have a lathe so can easily do the metal work. I read several posts from Jerry McCooglan’s experiences with this. Part of the issue in removing the flange is to insure there is enough sideplay on that axle but not so much that they can fall off the railhead.

I have a mix of LGB, Aristo and SVRR turnouts so am wondering if I am headed for troubles when trying to back these beasts thru them. I like the looks of the three axles over the two but in the end just want to be able to run them on the layout.

I have only the older Pacifics and I can get them to pull pull much better with some added weight in the boilers. I may add a couple pounds to them as well as work on the axle issues.

Since the center wheel set is the major supporter and the added resistance of the longer wheel base I may try running the blind wheel set on the front or back axle. I have not looked at doing that so might not be possible without them dropping off.

Andre’

#4

Andre’…send all your old heavyweight wheelsets to me…I’ll buy them…

#5

One important fact needs to be determined. How old are these cars?? The older 3 axle trucks are worthless except on major large radius track. They have been redesigned recently and unless the car is no more than about a year old the trucks are the old style. There is a gap of over 5 years where the cars were only available with the 2 axle trucks. The new trucks should be ok on 8’ diameter or better without modification. Less than that I really would suggest using the 2 axle trucks.

Warren

#6

Or buy the new trucks as replacements… what is your min track radius/diameter?

Ran 6 today (2nd gen) and once they are lubed, roll very nicely… I’d spring for the new trucks first.

Regards, Greg

#7

Sounds like your running to tight radius curve for the bad boys. Later RJD

#8

Greg…

We have a minimum of 5 foot radius…The cars need extensive rebuilding, due to a lot of damage that has been done to them. I have been able to get the replacement parts. The trucks are just part of the job. It is less expensive to move the bolsters to the centre and then body mount the couplers than to replace the trucks. Besides; the new trucks have only one little change to them…I have a new pair here, to compare. I can make that change very easily using styrene, but centre mounting and body mounting the couplers(Using the flex brackets) will make far better pieces of rolling stock out of them.

#9

Roger, or John, DeBerg, whichever name I should be addressing; I’d dislike having to be so formal and be addressing this to: “Mr.R.J.DeBerg”…this is an informal group, so please help me here… I’m “FRED”…hi there, and feel welcome.

The problem with the 6 wheeled trucks is the fact that the bolster is over the first axle, putting all the weight over the sprung axle, while the centre axle is not sprung.
They did this to make less swing on the end of the truck so that the truck mounted coupler would have less swing.
The truck tracks fine if the weight is over the centre axle.
We are body mounting Kadee couplers using the flex bracket, and centre mounting the 6 wheeled trucks.
These are “Heavy Weight Cars” and should have 6 wheeled trucks to look good for our operation.

#10

Today we finally checked out the Aristo Heavy weights. The main thing we had to do was to re-gauge the wheels, to the Aristo wheel gauge. We also placed a small shim of rubber above the journals of the outboard axels of the trucks.
We had already done some work on a lot of the Aristo WR switches; so the combination of all the adjustments made, has given great success with this project.

#11

The guys quit putting the 6 axel heavyweights on the track at the Botanic. They already removed the middle axel on each.

#12

I bought a set of 4 used heavyweights that had the old style 3 axle trucks with cast wheels joined by a plastic sleeve. Bad design–lots of drag, frequent derailments, wobbly wheels. Our layout has a steep 5.5% grade with curves in it, and the locos really struggled. I replaced the old trucks with new style 2 axle trucks, and they’ve been really painless since then. They roll easier and rarely derail.

I thought the switch to 2 axle trucks would bug me, but to be honest I never even notice anymore

#13
Fred Mills said:
These are "Heavy Weight Cars" and should have 6 wheeled trucks to look good for our operation.
I can agree with that, Fred. But some of us are not as talented at "fixing" and improving things. With my limited talent and resources I sometimes have to choose "works well" over "looks good". Ralph
#14

Mine look much better actually rolling and staying on the rails than they did clattering on the ties

I suspect there’s no circumstance in which you would not have more drag with the 3-axle truck, and since I was stuck with a non-prototypical 5.5% grade, it seemed like a better idea to get new 2 axle trucks rather than new 3 axle trucks

The old cast wheels were terrible!