dowlingm
Senior Member
70% low floor cars have more robust wheelsets/axles which can more easily take tight curves. But the Giambrone era commission said "100%LF"
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nfitz
Superstar
Isn't that a good thing? We've seen what mixed low-floor high-floor buses do, with no one willing to stand on stairs, or in higher area.
100% low-floor seems to be what most new orders are these days, world-wide. Hardly a Toronto thing.
D
Duck
Guest
This is true, but dowlingm makes a valid point that cannot be ignored. 100% LF generally means fixed bogies, which means "compromise" - ie, does nothing excellently. It's bad for ride characteristics and poor for track wear. The nose bounces all over because the axles are fixed to the car frames and are relativley close together, but are still far apart that the wheels are not really at good tangents to the rails on curves, so you get squealing and sliding and increased wear.
If you're ok with 70% LF then you get to have room for articulated trucks (think of the CLRV or ALRV's) which have low moving mass and can take curves like champs. They're just not as sexy.
There's only two 100% LF trams I can think of that have solved this, and one uses tricky software to turn wheels independently at controlled speeds (electronic differential) to keep the thing from derailing (Siemens ULF). If the computer goes down, the tram absolutely cannot move - it can't be towed or pushed or anything or it will derail. It's magic that they got it to work, but I would call it "Fragile".
If you're ok with 70% LF then you get to have room for articulated trucks (think of the CLRV or ALRV's) which have low moving mass and can take curves like champs. They're just not as sexy.
There's only two 100% LF trams I can think of that have solved this, and one uses tricky software to turn wheels independently at controlled speeds (electronic differential) to keep the thing from derailing (Siemens ULF). If the computer goes down, the tram absolutely cannot move - it can't be towed or pushed or anything or it will derail. It's magic that they got it to work, but I would call it "Fragile".
TheTigerMaster
Superstar
Does 70% low floor mean the same configuration as our busses: some of the vehicle low floor, with the rest having a step up?
If so, 100% low floor was clearly the way to go. We've effectively lost a third of bus standing capacity because of that step.
nfitz
Superstar
Have you heard squealing? I've stood at a couple of intersections while they are cornering, and they honestly seem quieter than the old ones, both on the straight-aways, and the curves.
Come to think of it, I'm not sure I've heard as much squealing overall in last couple of years ... hmm.
CapitalSeven
Senior Member
I've been on several 70% rigs and it's a very good configuration. But the doors are more towards the middle than with the 100% cars, where there tends to be one at each end. They work really well for LRT systems that are more towards the commuter end with longer trips, as the high-floor areas have a lot of seats that fill up and those passengers aren't bothered as much by the standees. You are probably right that the Flexities are the right thing for Toronto streetcars.
johntauren
Active Member
I find them squealing a lot when they crawl into Spadina, but the same is also true of the rocket subway cars. (less so the faster they travel)
drum118
Superstar
It was stated from day one that the new cars would not squeal using the loops like today fleets does.
First time I saw 4400 been tested, heard a low squeal while coming out of Hillcrest. Have heard the squeal at various loops as well cutting off one route to another. Can't speak for all the new cars since I haven't seen them at the loops or cut off. The ones I have seen do from time to time and not as loud as the current fleet as well not as long.
First time I saw 4400 been tested, heard a low squeal while coming out of Hillcrest. Have heard the squeal at various loops as well cutting off one route to another. Can't speak for all the new cars since I haven't seen them at the loops or cut off. The ones I have seen do from time to time and not as loud as the current fleet as well not as long.
EastYorkTTCFan
Senior Member
The only pace I've really herd them squeal is union but that loop is pretty tight and in a confined space
Amare
Senior Member
Of course they won't squeal like the old ones, since they're not 25-35 years old. Let's wait till 2035-2040 and see how they bad things get.
innsertnamehere
Superstar
Finally saw 4416 tonight, turning from northbound Shaw St. to westbound Queen St., doing a test run. It was the second new streetcar testing on Queen I saw on a single ride, 4407 was testing eastbound at Bay too.
Admiral Beez
Superstar
We've all heard the saying, they don't make them like they used to. I expect these new streetcars will have about 2/3 of the life of the current models before significant faults occur.
My prediction, assuming good health, is that I'll be returning and quoting this in 2026 with the units suffer advanced corrosion issues blamed on either their design or the materials used.
TheTigerMaster
Superstar
Maybe, maybe not. We'll see. So far the LFLRVs have been outperforming the TTC's reliability expectations. And the C/ALRVs we're exactly bastions of reliability. There are of questionable decisions with the design of those cars, from what I understand.
Admiral Beez
Superstar
My comment is driven mostly by my memory of the articulated buses, all of which were tossed, AIUI, due to corrosion and poor design.
EastYorkTTCFan
Senior Member
I thought they all had aluminum frames which led the TTC to have a saltless steal only requirement for buses which made it hard when they went to replace them a while back as there weren't many manufacturers using them.