For example, I have heard that a HO Kato SD90MAC or SD80MAC will pull anywhere from 40-100 cars by itself. That’s a big margin. I would like to know what modern (or what I consider modern, from the C30-7, SD40-2 era and up) locos you have and how many cars they will pull by theirself. Include the brand and model of the loco. If you have weighted your locos that’s fine, include them too even though they’re not considered “stock.”
I hope this isn’t a topic that gets repeatedly posted, I looked back about 100 pages and didn’t find anything good on it, so here it is.
i think just any “modern” or 6 axle unit made by a good company, such as Athearn Genisis, Atlas, Kato, etc. will be about the same in pulling power. The Kato SD90’s would have an actualy physical advanatge as it is a pretty big model, heck the real one is huge, there for would have more weight for traction.
As far pulling cars, that is tough. I can see the wide margin. While one guy might say he can pull 30, while the other can pull 60. The 1st guy has a smaller layout and 40 cars are in atleast 3 or 4 turns at anytime while the other fellow mights his cars good and straight at the big club layout. And that is assuming they are weighted right, quality cars, metal wheels and good track work. Alot of factors can play.
I have to admit thoguh, 100 cars sounds like a pretty big stretch. Even 70 would be a bit much, unless it is on perfectly level and straight track and that would have to be a pretty big freakin room.
I’d say there are quite a few factors concerning the pulling power of a locomotive–and three of the most important I can think of is 1: size of the layout, 2: maximum gradient and 3: minimum radius of the curves. Since I don’t model diesels–though I understand that today’s diesel models are for the most part EXTREMELY powerful–I can tell you that my steamers are all tinkered with to get the maximum pulling power for my layout size (HO, 24x18’) grade (max. 2.4%) and minimum radius (34") and their particular wheel arrangement. Because of the railroad’s size, I usually limit my heavy steamers to 25-30 cars, my medium locos to 15-20 and the smaller power (2-8-0, 4-6-0) to 5-10. Were my railroad larger, I could increase the length of my larger steamers with no problem, since my grades are not constant.
So there’s a lot that goes into it. Usually the reviews in MR and other publications are figured out for straight and level track.
Tom
The 40-100 car capacity for an SD90 or 80 is not that far fetched for the prototype. I crossed over the NEC track on my way to High school in the early sixties and counted 70 cars behind a single GG1 (rated at about 4600 HP).
According to a MR product review, the P2K SD-60 will pull 93 cars. They measure the drawbar pull in ounces and convert that number to an equivalent amount of cars. That eliminates grades, curves and track conditions from the equation. Here is a link to some MR reviews, you will need to go through the list and find the diesels so you can compare them.