Posts by Bill Walker


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21) Message boards : Cafe SETI : The train thread (Message 1641408)
Posted 14 days ago by Profile Bill Walker
The nearest we have is probably the Lickey Incline, 2 miles at 2.65%

Damn stupid way to build a railway!! Same as the line though Dawlish .....


It was assumed that cable or horse assist would be used on the steep bits back when you Brits built railroads like this. It looks silly today, but in 1832, compared to the roads that were available, it probably looked pretty cool.

22) Message boards : Cafe SETI : The train thread (Message 1641069)
Posted 15 days ago by Profile Bill Walker
I think many modern freight bogies also have some limited axle swing

No, they really don't.


Take a look at Figure 4 here. I'm sure I read somewhere about this showing up on freight trains in North America. Or maybe I'm thinking of passenger cars.

Found it! Maybe not in service, but tried on coal cars on CPR. Quote from page 676 of Wheel-Rail Interface Handbook edited by R. Lewis, U Olofsson. Flexible steerable bogies used on CPR coal trains since 1989, resulting in significant reduction in flange wear and tread shelling.

High speed passenger trains were tried in Canada back in the last century, but the problem still remains that nobody (private or government) wants to pay for the right of way upkeep this needs. Canadian freight operations are making good money right now and nobody in the industry wants to mess with that.

The Turbo Train between Toronto and Montreal in the 1960s to 1980s hit speeds of 140 mph on stretches of good tracks, but the scheduled times for the complete run then were only slightly better than today's diesel-electrics on the same run. Neither the Turbo or the modern trains regularly meet their schedules, as they are often held up by freights.
23) Message boards : Cafe SETI : The train thread (Message 1641063)
Posted 15 days ago by Profile Bill Walker
VIA Rail Canada trains currently go up to 100 MPH in some places


In Manitoba trains can get up to very high speeds on the 'National Hill,'
just out side of Winnipeg....



Oh now you've done it. The National Hill is supposed to be a secret. Even the people in Winnipeg don't know they have a Hill.
24) Message boards : Politics : Your patience levels? (Message 1640903)
Posted 15 days ago by Profile Bill Walker
Way back in the last century, I had a university room mate who had grown up on a Michigan farm. Part of his daily chores had been to collect eggs in the morning, clean them, and take them in to town to deliver to customers. After some customers said they would pay extra for "really fresh" eggs, he started keeping some eggs uncleaned, and then charged extra for them.
25) Message boards : Cafe SETI : The train thread (Message 1640682)
Posted 15 days ago by Profile Bill Walker
Chris I think the little weighted carts are being used to straighten the track, after it is laid, although in North America we use powered machines for this.

26) Message boards : Cafe SETI : The train thread (Message 1640491)
Posted 16 days ago by Profile Bill Walker
I think many modern freight bogies also have some limited axle swing, which helps as you said. Like the gravitational effects of slope, the power loss in a turn can be reduced by good track design. In this case, using large radius turns on modern rail beds. Power loss in the turn is also increased with speed increase. I watched a few unit trains loading coal in the BC interior and then unloading at Point Roberts on the coast. The loops at either end are the tightest radii on the run, and the trains are dead slow through these areas (for many reasons).

The total cost of transporting bulk goods is always a combination of capital costs and running costs. If you can amortize the capital cost of railroad construction and purchasing locos and rolling stock over many tons of freight, than very long trains on proper trackage remain one of the cheapest ways of transporting bulk cargo, as long as time is not a big factor. Second only to very large ships.

High speed passenger trains are a different calculation. If the distances are short (and therefore the capital cost of tracks relatively low) they can compete with airplanes given a good volume of paying passengers. Like in Europe or Japan. The same technology in the low population densities areas can only make sense if somebody else pays the capital costs, and if somebody subsidizes the running costs - like in China. Just my opinion, but it seems to be proven by the very limited number of profitable high speed trains in spread out, low population density, North America.
27) Message boards : Cafe SETI : The train thread (Message 1640014)
Posted 17 days ago by Profile Bill Walker
...so the lead loco isn't expected to pull the whole 99k tonnes.


Guys. Basic high school physics. the 99k tons (or tonnes) is supported by hundreds of wheels under the hundreds of cars. All the loco sees is the weight of the train times mu (coefficient of friction), plus slope effects. The reason railroads are so efficient and so cheap is that mu can be very low, less than .01 if the steels wheels and steel rails are well maintained. That means the loco sees 1%, or less, of the train weight on level ground.

Slope effect is minimized by keeping the slope of the rails very low. For modern railroads a slope of 1 in 100 (one foot vertical change for 100 foot length of rail) is considered steep. For a line built specifically for heavy load hauling a slope of 1 in 200 is more likely the maximum. Using a small angle assumption, that means the slope effect adds no more than 0.5 % of the train weight to the load seen by the engines. (An earlier post quoted a slope of 1 in 250 in the loaded direction for one of the heavy lines we are talking about.)

Modern freight cars, even two at a time, can generate very high loads at the couplers under high acceleration or heavy braking. So, yes, every car can withstand the sorts of loads seen on long freights. You just have to keep acceleration and deceleration to small levels, easily done with modern electronic controllers.
28) Message boards : Cafe SETI : The train thread (Message 1639952)
Posted 17 days ago by Profile Bill Walker
It makes sense on the face of it, build an ore refinery next to the ore mine and just ship the processed metal out (hundreds of tonnes), rather than the thousands of tonnes of metal ore which will be largely 'waste' oxygen.


Except that refineries last a lot longer than the ore supply does. Many refineries here in Canada have outlived more than one mine, because they have good rail or sea connections.
29) Message boards : Cafe SETI : The train thread (Message 1639197)
Posted 19 days ago by Profile Bill Walker
As much as possible, these trains are scheduled to run through the mountains in daylight and the boring plains at night.


In a classic example of accountants not giving a d**m, the last few years that CN and CP ran scheduled passenger service through the Canadian Rockies they scheduled the passenger trains to run at night, in order to allow the frieghts to run faster.
30) Message boards : Cafe SETI : The train thread (Message 1638919)
Posted 19 days ago by Profile Bill Walker
That's the third time this video has been posted in this thread in the last few days. Does anybody actually look at the links?
31) Message boards : Cafe SETI : The train thread (Message 1637909)
Posted 22 days ago by Profile Bill Walker
I haven't rode the GO Train here in Ontario in a few years, but they used to have an engine at one end, and a passenger car with a driver's cab at the other end. The trains ran a back and forth shuttle between the east and west suburbs of Toronto, and the engineer would move from engine to end car (or vice-versa) at each end of the run.

In this pic, the closest train is coming towards you, the driver is at the right (in the picture) front window.
32) Message boards : Cafe SETI : The train thread (Message 1637768)
Posted 22 days ago by Profile Bill Walker
A cool video from a few days ago, in New Brunswick. They have just had 3 major storms in 10 days, with some spots getting 3 feet of snow in total. This video reminded me of Bernie's camera falling over, I guess this guy had a better tripod!

https://www.youtube.com/watch?feature=player_embedded&v=Yja2VmZOfdA
33) Message boards : Cafe SETI : Mysterious Miscellaneous Tool Time V6 (Message 1637363)
Posted 23 days ago by Profile Bill Walker
Used to hold a part while it is polished or turned?
34) Message boards : Politics : Your patience levels? (Message 1637137)
Posted 24 days ago by Profile Bill Walker
A true democracy respects the wishes and needs of the minorities. Turn off your bloody TV when it comes on.
35) Message boards : Cafe SETI : Mysterious Miscellaneous Tool Time V6 (Message 1636822)
Posted 25 days ago by Profile Bill Walker
Well, on a technicality I have to give this one to J. Mileski. It is for measuring spoke tensions. I thought it was just a wire tension device when I found the picture (and that was what I was looking for), but on reading about this particular one it is intended for spokes. You came a close second Admiral.
36) Message boards : Cafe SETI : Mysterious Miscellaneous Tool Time V6 (Message 1636627)
Posted 25 days ago by Profile Bill Walker
Pressure relief valve


No.
37) Message boards : Cafe SETI : Raccoon Update XX I - All are welcome in the Critter Cafe (Message 1636603)
Posted 25 days ago by Profile Bill Walker

OMG! He's not crazy, he's just Canadian!


Not about being crazy or Canadian, it's about being forward looking. I did it because I knew what the restaurant would look like after a dozen 6 year old boys got finished with it, I assume Mr. Es does it because he knows what the restaurant will look like when Ms. Es gets finished with it.
38) Message boards : Cafe SETI : Raccoon Update XX I - All are welcome in the Critter Cafe (Message 1636589)
Posted 25 days ago by Profile Bill Walker
All right you lot, get your minds out of the gutter. I'm talking about this kind of Beaver.
39) Message boards : Cafe SETI : Mysterious Miscellaneous Tool Time V6 (Message 1636588)
Posted 25 days ago by Profile Bill Walker
Sorry for the delay, but I've just spent 2 hours digging out half of my driveway. Taking a break now, before doing the other half. Here is an easy one.

40) Message boards : Cafe SETI : Mysterious Miscellaneous Tool Time V6 (Message 1636356)
Posted 26 days ago by Profile Bill Walker
Pulling teeth?


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