I am working on a Rivarossi Allegheny (2002 version, DCC ready, rubber traction tires). It is an impressive puller, being able to pull about 40 stock weight freight cars up a 2% grade without slipping. However, I have read that it is supposed to be able to pull about 70 or 80 cars up the same grade without slipping.
I have replaced the original traction tires, which wore out, with 16mm dia. "low profile" traction tires from LoveTrain Hobby Works.
I have added about 4 oz. of tungsten to the model, most of it in the back of the locomotive. The center of balance is currently between the 4th and 5th sets of drivers. The traction tires are located on the 5th set of drivers, and the gear tower connecting the rear engine to the locomotive is between the 5th and 6th sets.
I installed a Soundtraxx Tsu-2200 decoder, with BEMF control adjusted so that the motor will only slow down a little when going uphill. I seem to remember that at one point I turned down the BEMF control and was able to pull more cars uphill because the drivers wouldn't break loose as easily. It is currently adjusted so that the drivers will spin if the locomotive is held stationary at speed step 1.
Any insights into why it can't pull as much as it's supposed to or how to improve its pulling ability would be very much appreciated.
Thanks in advance.
I’m sometimes dense, but is this a power or a traction problem? If it starts spinning, it has enough power to overcome its own weight and inertia. So, that’s a traction problem. You’ll need more weight or better stickiness at the tire surfaces, or it could actually be somewhat improved by different weight distribution. Or, reduce the “trailing tonnage” either via loss of mass or by loss of rolling resistance. That could come via reducing car count or merely by reducing the grade. Or tuning axles in the rolling stock.
Probably some of all of these will end up with your success. Clearly, the answer is not going to come from traction tires.
Also, do we know what the anonymous claimants did to get 70 cars towed easily?
Thank you for your reply. Yes, the issue is a loss of traction. The cars already all have full metal wheelsets, and it's a museum layout, so unfortunately I can't reduce the grade %.
I don't know if the traction tires have the thickness needed for constant contact with the rails.
Do you know what I would want to do to improve the weight distribution? Ordinarily I would try to put the center of weight in the center of the drivers, but the traction tires and articulation make it more confusing.
You think the original traction tires had more friction to them than the new ones I installed then?
According to MRR's most recent review, the Allegheny they tested was able to pull 112 cars on level track and 20 cars up a 3% grade. Considering how heavy 40 cars are on a 2% grade, that's still impressive!
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If Hornby International can’t help, maybe turn to a product called Bull Frog Snot. Waltzers sells it. There are videos on YouTube you can watch. The product tends to go hard in its bottle over time, but I saw a credible thread on another forum that adding three or four drops of water every few months keeps the contents fluid.
selector If Hornby International can’t help, maybe turn to a product called Bull Frog Snot. Waltzers sells it. There are videos on YouTube you can watch. The product tends to go hard in its bottle over time, but I saw a credible thread on another forum that adding three or four drops of water every few months keeps the contents fluid.
Thanks for the suggestion. I've tried BFS before, unfortunately it isn't allowed on the museum layout because of the dirt it tends to pick up.
Never mind, I figured out my mistake. It turns out I put together the bottom of the rear engine together wrong, which allowed the drivers to move around too much. This caused the drivers to not be in contact with the rails the entire time, reducing traction. This also nearly managed to shear clear through the crankpins. So now I have to replace the side rods and crankpins, but at least I finally know what the problem is.
I have an Allegheny, and I have watched mine pull 80 cars up a 2%, 38" radius helix with no problem.
Sounds to me like rolling stock that might not be very free rolling?
Sheldon
I thought there was a gentleman on this forum that has pulled over 100 cars up a 2% grade?...maybe it was another forum??
Brian
My Layout Plan
Interesting new Plan Consideration
railandsail I thought there was a gentleman on this forum that has pulled over 100 cars up a 2% grade?...maybe it was another forum??
Maybe, but the important point is not all cars are created equal, so car counts are not an accurate measure of pullng power.
Car weights vary, rolling resistance varies, track conditions vary, curves add resistance.
My Broadway N&W Class A will out pull the Allegheny, but only by a small margin.
Virtually all my cars are fitted with my special truck setup - Kadee sprung metal trucks refitted with Intermountain code 110 metal wheel sets. Extensive testing showed this to be more free rolling than most all rigid frame plastic trucks, and to track better, especially on long trains.
This is one of the videos I remember,.
https://youtu.be/21tue_hc1iQ
But I think this same fellow did a video of a single engine pulling?
Thank you all for your advice and information. It turns out I just assembled the rear engine wrong, which led to the drivers being able to move around too much and causing the side rods to nearly shear right through the crankpins. I have to replace those parts now, but at least I know what the problem is and how much it's supposed to be able to pull.
ATLANTIC CENTRAL I have an Allegheny, and I have watched mine pull 80 cars up a 2%, 38" radius helix with no problem. Sounds to me like rolling stock that might not be very free rolling? Sheldon
The rolling stock is all equipped with stainless steel axles. Most of it is free rolling enough to roll down a slight grade on its own at least.
What were you using to run your Allegheny? DC or DCC? What kind of decoder? What speed?
Thanks in advance for any other information you can provide.
Shades_10318 ATLANTIC CENTRAL I have an Allegheny, and I have watched mine pull 80 cars up a 2%, 38" radius helix with no problem. Sounds to me like rolling stock that might not be very free rolling? Sheldon The rolling stock is all equipped with stainless steel axles. Most of it is free rolling enough to roll down a slight grade on its own at least. What were you using to run your Allegheny? DC or DCC? What kind of decoder? What speed? Thanks in advance for any other information you can provide.
It was running on a digitrax DCC system on a friends layout. Not sure about the decoder, the loco is now strictly DC, decoder removed and sold years ago.
I know the specifics of the layout, because I designed it for my friend.
The layout is basically level except for two helixes that move trains in and out of lower level staging.
The train started out on the main level, on mostly level track, it traveled down the first helix and back up the second one several times around the layout. The whole double track mainline length, visable and staging, is about 400 ft. Both helixes are 36" and 38" radius at 2% grade. The helixes are arranged to that both inside tracks are down, outside 38" radius tracks are up.
The loco did have the factory traction tires.
The 80 cars were a mix of typical Athearn blue box and similar products from other brands, most equipped with REBOXX wheel sets.
On that same evening, my BLI N&W Class A 2-6-6-4 out pulled the Allegheny by about 15 cars.
Speeds were in the 25-35 smph range, yes rather slow, no attempt was made to stop or start the train on the grade.