I blame anthropomorphism… Micky Mouse, Bambi, Thomas the Tank Engine…
it’s easier to think of the train as “stupid” and /or having a will of its own than to get down and fix the track or the problem with the car/loco.
If anyone’s interested… I give long answers to questions like this because I believe that if I understand what the real thing is doing I have a more logical approach to get my immitation of it correct and effective. (affective)?
The only part of a train that gets significantly steered by the rail is the point of contact between the leading wheelset and the rail head.
Once that wheel has been started to deflect everything else should be following it.
This is why steam locos had leading trucks (especially as fixed wheelbases got longer) AND why curves start with easements.
That said… the only time a non-powered wheel isn’t rolling itself round a curve is that leading truck OR a car being propelled rather than pulled. One reason for pulling trains is that they follow in line better than being pushed ahead in a line… which is why loops are prefered to blind roads.
Oh, yes… one thing that you might do is make a jig to build your common crossing metal work on and then transfer it straight into the switch and guage it to the straight stock rail. The reason for always laying the straight stock first is to give you a fixed datum from which everything else builds… This is far easier than floating around… you are also using the longest single element (except the curved stock rail) of the switch… so your datum runs right through. You don’t get this if you try to build from the common crossing.
Clearly if you are building a Y you identify one stock rail as the datum… I would use the one further away from me. In a curved switch I would adopt the longer stock rail.
In a three way switch I would use the straight stock if it was a hand
Terrific pics!!!
Glad you’re still alive… and not locked up…
As I said “A rail wheel should ONLY ride on its tread NEVER on the tip of the flange”. You seem to have something of everything going on on this switch. The shine indicates where a wheel rolls brilliantly (sorry).
The damage to the wing rail shows what a lot of traffic getting it wrong does to a rail… that is hammer blow damage… you can see where pieces will begin to flake off.
I’ve never seen damage like that in yards, certainly never out on main line.
It’s not just the rail tha’s getting damaged… every wheel that hits that is having it’s life shortened.
I can’t tell what the material is… it looks like the tips of flanges ARE touching material in the frog and cutting a path… it looks like a greasy mess… is there a flange lubricator nearby? Could you see any reason for wheels striking that wing rail end?
PLEASE use a telephote from a bridge!
At least take someone to act as lookout … you never know when soemthing may be moving… even if you have your scanner on.
I didn’t take those pictures. In the pic you can see all the closer I get to the tracks. They are adding a new switch and track and I asked one of the NS guys if he would take some pics for me. He was more then happy to do it. I would never venture out into the main line even though you can see a mile in both directions.
is there a flange lubricator nearby? Could you see any reason for wheels striking that wing rail end?
No, there isn’t. But for some reason when the wheels go over that switch they make a hell of a noise. Even though there is 5 other switches near it that is the only one that makes that sound. If you look at the other side it has a huge dip wore into it. Maybe that explains the greasy mess.
Great to hear that!
Obvious but at 60 a train will cover that mile in 1 minute… the time you have to see it, react and get out of there.
So I’m really delighted you work safely!
I think that that damage (and the dip opposite) explain the noise! I should think that it sounds like someone whacking it with a very big sledge hammer.
I was recently working on the track when a train went by on the slow line. I’d never felt the whole formation shudder like the wheels going over that joint. I phoned it in and got it inspected. Line was OOU (trains diverted to the fast) until the joint had the ballast under it repacked and the rail bars replaced.
Shouldn’t think the grease is part of the damage problem. As with driving on the road the railroad keeps grease off the rail as far as possible… it stops traction for both pulling and stopping. Flanges get greased only on severe curves to reduce wear to both the rail and wheels.
I’m glad to hear you didn’t take those pics. I was seriously about to go off on you about safety (having had a closer encounter than I’d like to admit).
I wouldn’t stand on the tracks any sooner than I’d invite a gangbanger to point a gun at my head.
Standing on the tracks is bad news, that’s for sure.
Actually the guy who took them for me thought I was a real nut case. He has seen me at that spot almost everyday. He can’t understand why someone could be that hung-up on trains. He can’t stand to be around them. Maybe it’s because he works with them everyday. I know if I worked at a McDonalds you couldn’t get me to eat a Big Mac for anything. In fact he actually loaded a few new frequencies into my new scanner that I didn’t have so I could hear everything NS is saying. He also explained some of the signals, different pusher tracks, and some of the things I hear on the scanner that I didn’t understand. Actually he was very helpfull.
At some point back in the thread, someone wondered about the rigidity of trucks and how much wheels moved up and down.
When I commuted into Toronto, I could watch trains coming in on parallel tracks. I could see the axle boxes on diesels moving up and down – looked like several inches – going over a long series of double slip switches and diamonds. I know that there were problems with the roadbed – places where mud was coming up through the ballast – but it looked like the loco was moving in a straight line and the axles were bobbing up and down.
The same goes for freight trucks, although I never watched them through that spot. They’re designed so the side frames rotate a bit around the bolster. Compare the springs on a loaded and unloaded car.
I got a little crazy and modeled up a Frog in CAD. This Frog is shown with an RP25 HO wheel, but does not include the permissable taper of the wheel.
The standard NMRA track flange width and gap are modeled.
Check it out…
It’s not easy to tell from a drawing that you can’t rotate around on your screen, but I can assure you, the wheen is always supported by its rolling surface.
For all I know, most people know this already, but I’m just realizing it for the first time. As shown in the fourth picture here, the wheel is supported by the wing rail even as it just first makes contact with the Frog.
This jives perfectly with what Tim (Fastracks) said about the importance of making the frog point extend as far as possible. If you don’t - if you cut the point short, you could have “drop in”
So what’s the “click” and small dip in the frog I’m feeling on my scratchbuilt turnout?
I attribute it to two things:
I ain’t a perfect turnout builder.
The wheel actually has a taper. That taper means the outside of the wheel is smaller in diameter than the inside. As the wheel transitions from being supported by the point of the frog to the wing rails, it theoretically drops down a tiny bit - the amount it drops down depends on the angle of the taper.
I told you I was dimented.
As for Semi-Scale wheels - thanks for the advice Tim. I think I’m thinking along the same lines as you. Once you make the wheels narrower, the flange should be adjusted accordingly… etc. - it could snowball, as you said. You’d really need a new “HO semi-scale standards gauge” for laying your track. It’s really like Proto:87 in that you need a different set of standards.
Especially because I haven’t even mentioned tolerances yet, only nominal dimensions. Throw tolerances into the picture, and my images below could become worse.
I should add, in conclusion, NO, the wheel flanges do not touch the bottoms of turnout frogs. The wheels are supported by the wing rails.
That’s my story and I’m sticking to it - well, unless I’m wrong [:D]
Edit #1: I’ll also add there is evidence of the wing rail supporting the wheel through the gap in the Frog in the “real world” turnout pics above - the shiny surface tells that story. It would be easier to see from a direct overhead view, but I’m not going to encourage anyone to take any more pictures on the train tracks, that’s for certain.
Edit #2: In re-reading Tim (aka Fasttracks’) post above, he also mentioned the width of the wheel tread spanning the gap. Now I totally understand what he was talking about.
8500HPGASTURBINE
Hi. Any chance of another safe look at that damaged switch this weekend?.. A close up and an area shot of that damaged stock rail might help us understand more.
Anyone else want to SAFELY add pics? Have a good/safe weekend [:D]
Someone explained here that the wheels increase in diameter towards the flanges so that the axles can turn as one unit on curves. The outer wheels have further to travel, so as they slip toward the outside of the curve under g-forces, they also ride up onto a higher diameter, thus allowing the whole wheelset to follow as a single unit; no scrubbing and premature wear of the rolling surfaces.
The last two pics from either side and the opposite direction would be good (I assume you’re using digital)… then all four directions from further back …some to include the stock rail and the dip you describe in that rail… and some close ups of whatever is going on there… This lot should show us how that damage is coming about.
Thinking about it I suspect that if that stock rail is bad enough what is happening is exactly what we don’t want to see happening at the frog… the wheels are dipping in so badly that the back of the opposite wheel is being moved inside the “Back to back” clearance allowance and striking the rail that shouldn’t normally see any contact at all. It is unusual that the end of the wing rail is being hit… and has been left long enough to get that bad.
If this were happening with the frog the middle of the opposite (protecting) guard rail would be seeing something like this damage… probably a gouge.
The thing I wonder is whether the wing rail is doing it’s job and deflecting wheels in the direction they should go or doing more damage. To some degree it might be better if a car de-reailed and created the situation in which the track got fixed.
I would guess that they are maybe not fixing the damage because this switch will come out all together when the new track comes into service… it is something of a stretch of “defered maintenance” though.
You have new track being laid???
WOW! What an opportunity! Without driving them nuts can you photograph / get them to photo the equipment (especially when they satrt using on-track-machines (OTMs) like tampers? Can you get any pics of the build up of the formation… this would brilliantly illustrate what I’ve been going on about in "ballast "posts.
You could become a Forum Hero!
I realise that this might be a lot of time and pics.
Oh, yes… I suspect that that flangeway has crud/grease that the wheel flanges are cutting through in the bottom b
Man you don’t let up [;)] Just kidding my friend. Actually I did get one of the crews to take more for me. I will post them tonight or tomorrow morning for sure. I think they are what you are looking for.
When I was a kid in the 70’s, my grandfather took me to the Buckeye yard. Lots of switches there! Every car and loco that passed through a switch “Clicked” Ever been on a passenger train? I know that every time we get put onto a siding, or anything that has a switch or a diamond, you can hear and feel when the wheels pass through the switches and cross tracks.
Like earlier posts have said, “The Laws of Physics do apply.” The only way we can get a non wheel click switch is to wear ear plugs. It’ll still click, we just won’t hear it.
So, the wheels flanges should not touch the bottoms of the frogs. If they do, then it’s time for some repair work on the track.
Alright, I have a pretty good understanding of what’s going on in a turnout frog now. The wheel is supported by the wing rail as it comes into contact with the frog point.
But how about a 90degree crossing? There is no wing rail to support the wheel going through the gap. They must really click!!!
Prototype flanges are much thinner though, so the width of the gap is much less in relation to the diameter of the wheel than our models.
