I have never seen sprung trucks for any engines. What's the reason why companies have not done this? Most cars now have sprung trucks and it makes the car look so much more realistic
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Originally Posted by Bagelman:
I have never seen sprung trucks for any engines. What's the reason why companies have not done this? Most cars now have sprung trucks and it makes the car look so much more realistic
Many steam locomotives do indeed have sprung drive wheel axles. However, the vast majority of the "sprung trucks" on scale freight cars are so stiff, that nothing is accomplished, except for appearances, anyway.
In my opinion, using sprung drive axles on diesel/electric models might tend to cause tracking issues, on much of the tight curves used on 3-Rail layouts.
Most people complain about changing tires, now throw in sprung trucks and listen for the rants.
To the best of my knowledge, 3rd Rail and/or Kohs have done this. You're talking high-end stuff here.
Gilly
I have 3rd Rail locomotives with sprung drivers, I haven't seen them on any Lionel/MTH/Williams, etc.
Lionel's Y6b has sprung drivers... found out the hard way while changing tires...
Brass HO had done sprung drivers and trucks for years and they are much smaller than O scale. I am sure cost, marketing and manufacturability are to be blamed for O scale locos not having sprung wheels. But with today's fairly inexpensive labor from the far east, It is a very easy thing to do it on O scale. All that is needed is approval of the marketing guys, such as Lionel and MTH. Engineers will do it in a snap.
I believe that sprung drivers and trucks in a loco will make it run better and more smoothly on the tracks, assuming it is "sprung" correctly for the weight and the possible loads it will pull!
I would have rather seen sprung wheels and drivers and more details, lights and smoke effects on the VL BB than the depleting load...for me anyway.
Do you have a picture of the 3rd rail engine with the springs?
Originally Posted by Bagelman:
Do you have a picture of the 3rd rail engine with the springs?
The springs on the driver axles can not be seen, as they are up inside the frame. Thus, photos really do not show anything.
Weaver brass steam locomotives have sprung drivers, and I seem to recall that an old Williams brass steamer I used to have also had sprung drivers. Can't verify the Williams because I don't have it any more. Sometimes the sprung drivers really work, and sometimes the springs are so stiff that it doesn't make any difference. Gary at Weaver sent me a set of softer springs for one of my locomotives that had a traction problem. I have never seen a diesel with sprung motor trucks, but that isn't to say that one doesn't exist somewhere.
Sprung drivers are an expensive item to include on a steamer. They also can be a source of assembly errors and other problems, and they can be a real pain to work on. The side rods have to be segmented like the real ones, which adds to the cost and complexity. I don't see how sprung drivers on a diesel would add much or be cost effective.
Lionel's Acela power cars have working springs on their powered trucks. This becomes apparent to anyone who has changed out their traction tires 
---PCJ
Most O Scale 2- rail has been sprung since the late 1930s. I machine my own main frames, and usually carve slots for square brass bearings. I then drill the spring seats, so that, some day after I am gone, some enterprising kid will be able to insert springs with simply a screwdriver. I use rubber or cork pads instead, since i have seen no difference in actual performance. My five axle locomotives do have springs on the front axle, to prevent climbing the rail on superelevated curves.
It's been almost thirty-six years ago. I had a Williams Brass O-Scale Big Boy with independently sprung drivers w/traction tires. It was a stump pulling beast. It would pull 150 plus car no problem. One day a fellow club member brought his brand new Lionel BB to a club meeting. He challenged me to a pull-off. We hooked the tenders together and we were off. My Wms BB just flexed it's muscle and dug right in. No contest, the circle L BB just kept smoking it's tires and getting so hot you could hardly touch the boiler. My Wms BB just kept dragging the other BB for a total of 125 feet. The ol' boy offered me more than twice what I paid for my BB ( You betcha I took it)
To this day I've yet to see any other engines with independent springs on each axle.
BTW Jim Barrett hooked a pound meter to his engine and pulled the meter a part.
"Pappy"
having sprung trucks and sprung drivers on model trains is like super elevating your track, it looks nice but does not have any positive effect on performance. it may actually have negative effects on performance. most brass steam locos have sprung drivers and in my personal experience with 2 brass Weaver they pull less of a load than a similar loco without sprung drivers.
IMO one of the best ways to check out new track work at vertical curves, diamonds and turnouts especially curved turnouts is to use a 10 driver unsprung steamer.
We use a Lionel PRR 2rail J and MTH PRR 2r T1 to check all track work. Nothing more unforgiving IMO, than a rigid unsprung Lionel or MTH PRR J or T1.
Samhongson (sp?) built the Williams 2r engines I started out with in the early 90's.
I can attest that my particular Williams BBs, Challengers and cab-forwards all had sprung driving axels. An easy check is to hold the boiler down while you try to lift the axel end with your fingernail.
My first run 90's MTH rigid frame Espee Daylight actually fell over once running over a less than perfect OP slip. (Of course less than perfect OP slips were the norm.)
This statement must have factual variations but I have been under the impression that: most or all diecast steam engines were rigid axels.
If the springs have the correct spring rate then they should improve adhesion to the track. Thats why virtually all road vehicles have them, to keep the wheels on the ground. Try replacing the shocks in your car with solid struts, then take a corner and see how well it stays on the road. No doubt most models are not engineered with the proper spring rate so I wouldn't expect much difference but I don't think springs would decrease drawbar pull. Thats mostly a function of weight and where is distributed. Brass engines, smaller ones in particular, have their weight foward of the driver centers. Die cast have their weight distributed more evenly.
BTW is regards to Kohs, don't many of the newer offerings have actual working leaf springs like the prototype rather than coil springs?
Pete
Originally Posted by Norton:
If the springs have the correct spring rate then they should improve adhesion to the track. Thats why virtually all road vehicles have them, to keep the wheels on the ground. Try replacing the shocks in your car with solid struts, then take a corner and see how well it stays on the road. No doubt most models are not engineered with the proper spring rate so I wouldn't expect much difference but I don't think springs would decrease drawbar pull. Thats mostly a function of weight and where is distributed. Brass engines, smaller ones in particular, have their weight foward of the driver centers. Die cast have their weight distributed more evenly.
BTW is regards to Kohs, don't many of the newer offerings have actual working leaf springs like the prototype rather than coil springs?
Pete
in the real world this would be true, in the model world where scale weight and placement of that weight is incorrect as well as spring rate. the wheel with the traction tire will naturally lift and slip under load. the other drivers without traction tires are of no help. if all wheels had traction tires it would be a different situation, engine weight would determine traction. the wheels could not lift and put grip on the bare metal drivers.
You're probably right John, but the 3rd Rail engines I have are the older models with no traction tires, so maybe the springs help.
