Thanks for the comments.
I have a few videos out there that might answer some questions. Type in sssisskokid on youtube. I think I have a playlist of 15 or so.
It is good to see the numbers some of you get match with mine. Yes, all the numbers seem on the low side perhaps, but these are the smallest of the small in my roster (except the mountain). And all are out of the box Bachmann Spectrum..no brass, no weights, no rubber tires etc. So yeah those fractions of an ounce are correct. Of course my Y3bs and a few others do better for traction, but steam locos are poor pullers generally because there is little weight added in the factory and all the drivers split the traction to a greater degree than a diesel.
Here is the companion video about larger steam locos https://www.youtube.com/watch?v=8KHxw-Ta6-s You can imagine that there is a diminishing return on the traction of a larger steam loco, whose weight is distributed over more and more wheels. The heavier 2-8-8-2s are not significantly better pullers than a 4-8-2.
However, when a friend had over his brass Y class, we forgot to measure the tractive effort, but it is a very heavy beast.
My best pulling locos (ones I would use with a track cleaner for example) are perhaps a couple of SD45s or SD60s which together pull closer to 6 ounces.
Grade and tight curves add drag significantly alright. My big test for pulling is that 4 per cent grade hill. But still, all steel wheels are a big help and I am still surprised how smoothly trains can run.
Very nice video and interesting info you have shared. Would like to see more of how you creat/built the sound cars. Nice background photo/mural too!
-Bob
Life is what happens while you are making other plans!
The best video I have seen in a long time. The WOW factor is present in all aspect. Thanks for sharing.
Jack W.
while the drawbar load for 12 small ore cars is only 0.2 oz (friction), what about on a grade?
for grades up to 10%, the drawbar force increases by approx car weight time grade / 100. A 4" car should weight ~3 oz (NMRA guideline). On a 1% grade, the drawbar force increases by 0.03 oz. or for 12 cars, 0.36 oz.
The total drawbar force including friction would be 0.56 oz. A 1% grade might be a problem for a locomotive that can only pull 0.5 oz.
greg - Philadelphia & Reading / Reading
"One difference between pessimists and optimists is that while pessimists are more often right, optimists have far more fun."
Interesting results, although the numbers seem on the low side to me. It did prompt me to get out my pull meter, though, and I tested several locos.
A brass Mogul (ex-B&M B-15) showed at 2.4oz., as did my Bachmann 4-6-0s and a Proto USRA 0-8-0.
Slightly better was a brass 0-6-0 at 2.8oz, and an Athearn Mikado at 2.9oz. My Bachmann 2-8-0s came in at 4.4oz., closely followed by a Bachmann USRA Light Mountain with 4.5oz.All of these locos have been modified with additional weight.
While I don't normally run diesels, I did test a few. An unmodified Atlas S-2 came in at 3.1oz., while a re-motored and ballasted Athearn Blue Box geep showed 5.1oz. and a ballasted Model Power FA-2, with its original motor, hit 5.4oz. A bit of a surprise was the one diesel which I do run often, a Rivarossi combine which I've made into a doodlebug. It showed a pulling force of 4.4oz., not bad for a can motor running a single truck out of an Athearn Blue Box F-unit.
Pretty-well all of these, the switchers and doodlebug excepted, normally run with another locomotive due to the numerous grades and curves.
Wayne
https://youtu.be/oSzxBE9Ga8Y
Here are a few screen shots from a recent video (link above) showing some numbers for my shays, climax locos, decapods etc.