Large Scale Central

Benchwork Underway Finally

Track and Trestles
#1

Celebrating labor day, as well as the arrival of my 38-ton Shay and the anticipated arrival of some freight cars, with the construction of the left bench for the Marin Coast and Hillside Railroad. The bench is a simple one. Basically a table with a triangular end to ease the look and allow for a smooth turn of the track. We are six feet wide at this end, and will be seven feet at the other end, about 25 feet away. I get a dogbone whether I like it or not. Once the other end is made, and the loop is created, we’ll start the ascent up the hillside. The natural terrain is a 2:1 slope. Switchbacks anyone?

#2

Actually, I misspoke. there will be no switchbacks, but a looping set of curves, with a prototypical maximum grade of 7%. Yep, you heard right!

(http://demo.ejus.net/depts/lb/main/crm/PhotoAlbums/railroadalbum/muirinn.jpg)

#3

Looks like you have the right setting for your intended build.
That was a neat little railroad going up Mt Tam.
Looking forward to enjoying your build.

#4

don’t be afraid, 7% is doable.
on my last layout i had 7% .
single motored LGB stainzes (weighted to 5 pound) could draw three to four two aixle - one foot long cars uphill.

#5

Thanks Korm. I feel confident with 7 % here and there, with whatever adjustments are needed to make it work. We’ll do a few test grades pulling cars.

#6

somewhere i had read a very elaborate post, about how to calculate the weifght of the cars against the drawing power of the locos. - and promtly forgot the details.
(power per aixle, draft per aixle, additional draft for grades and curves - that guy thought of everything)
but when reading, i had calculated, that for a two aixle loco between 4 and five pound are the optimum weight, to bring all power to serve.
what i remember also, that R1 curves equal more or less to 1 or 1.5% of grade.
when i read that post, i understood, why my big hauler with one motor, but three aixles and big wheels didn’t make the grades.

(btw on a straight grade of 8%, i just used a very coarse sandingpaper. sideways!
the rails didn’t look nice, but my trains got up the hill.)

if you look here: http://kormsen.info/landscape/background/
these grades are 6% on straights. at the ends are R1 curves with 4% grade.
i tested that to have 0-4-0 locos with motorised 0-4-0 tenders and can haul up to 14 aixles (five to six foot long strings of cars)

#7

I read somewhere that metal wheels add considerable weight that must be pulled up every grade. Being a bit slow, I guess, I’d never thought of this factor before then… (duh) 'Course, I come from a smaller scale (1:64 on 9/16", or Sn3) where the weight of metal wheels wasn’t as much of a factor as it is in LS. No questuion those metal wheelsets add considerable weight to our cars…

But I only use metal wheels nonetheless, run short trains.

Still, if you’re running battery power you might want to stick to plastic (ugh!) wheels if you want to haul cars up steeper grades like this… Just a thought, FWIW.

Keep us posted, Michael! :wink:

#8

what metal wheels add in weight, they add less in friction.
in my eyes - the biggest advantage of metall wheels is that they add wheight with a very low point of gravity to cars.
with sharp curves, as i have to use indoors, that is a gain.

#9

Well, experimentation will give me some initial results, I guess. I may come to want more than 14.4 volts, for example, and I expect to confine the 4-6-0 Big Haulers to “sea level”, leaving the ascension on the steep grade to the Shay and the Porter, which would be closer to prototype anyway. I expect fairly short strings of fairly short cars anyway, again, closer to the scenic railway prototype. I want to run some local freight too.

Of course, the experimentation will have to make guesses on the impact of track dampness (bad) and rail corrosion (likely good, for the friction). I like the idea of sanding sideways!

#10

i just found out, that high voltage is not the important point at going uphill. the Amperes seem to be more important. (don’t ask me why)
i just combined computer transformers with LGB dials. at 12 volt input to the dial my trains still race too much.
i am planning to rewire the things, so that i get less volts.

#11

Understood, Korm. In my case, I am using speed controllers that use PWM, so more volts translates in my case to more available amps. Actually, I am told that the 7 amp speed controller is too wimpy for my shay, so I may have to put in something beefier.