Curve riser pitch angle question??

[KRM]

laz 57

What I did to make the track have a pitch to the inside of a turn is take a 12 gauge peice of isulated wire and put it under the ties of the outside edge.  Brings it up about an eight of an inch and makes it look good.

laz57

LAZ,

That is more than what Frank53 does with the 1/16" spacers and I have tried then on flat curves and they are nice too. Your right,, 1/8" pitch looks nice and is about what my 5% is and it works well at least on wide elevated curves. Would love to see some pictures of your work on this.

[laz 57]

What I did to make the track have a pitch to the inside of a turn is take a 12 gauge peice of isulated wire and put it under the ties of the outside edge.  Brings it up about an eight of an inch and makes it look good.

laz57

[KRM]

quizshow904

Related question: Where can I find info on how much of a grade increase should I plan on for conventional o gauge engines? I am using Gargraves Phantom SS 3 rail flexible. I have the RR 5.0 software and it has a grade tool in it, but you have to tell it the amount of rise per foot of table length.

On advice, I used 3/4" grade increase per foot and that is shown in the pictures and videos on page one. I think that comes to something like 5 to 6%. It is a bit too much for some postwar engines even with magatraction if it is a long consist. Traction tire engines seem fine with it but you have to power up and down when driving over it. If I were to do it again I would use less but then you need more table. Tough call. The angle cut is at progression from flat to 3 to 5% and back down to 3 to flat. It works fine on 072 and 054 curve but I now think 3% Max pitch is plenty.

Hope this helps.

[rtraincollector]

I believe the rule is max 4% but if you have any magnatraction you just lost it as it won't help with SS track. I would look at something like 2.5% to be honest.

[quizshow904]

Related question: Where can I find info on how much of a grade increase should I plan on for conventional o gauge engines? I am using Gargraves Phantom SS 3 rail flexible. I have the RR 5.0 software and it has a grade tool in it, but you have to tell it the amount of rise per foot of table length.

[quizshow904]

even on the flat part of a table?

[overlandflyer]

bringing up the helix designs are, of course, extreme examples of tight, long duration curves, or in fact the worst case for forces vs. tracking.  in general, with wide radius curves, even though it's not going to make much of a difference in operation or traction, a slight super-elevation is going to look better than a flat track.

i'd say, go for it!

cheers...gary

[Buckeye Riveter]

overlandflyer

lionelsoni

Unfortunately, on our unrealistically sharp toy-train curves, the forces pulling cars to the inside of the curve usually overwhelm any centrifugal problem.  So anyone considering superelevation should be aware that it may create or make an existing problem worse.

as weird as this sounds, i can attest to its truth.  i discovered this once when making a helix display with a friend.  slightly raising the inside rail on the smaller diameter curve actually helped the train stay on the track better.  our initial attempt at super elevation constantly resulted in the train being pulled off to the infield.

I saw the same thing on an HO layout with a helix about 30 years ago.  The builder was putting in a negative superelevation (inside rail high) to keep all the cars on the track when ascending. Of course, I looked at it real hard until he explained his reasoning.  He also used the helix for storage during operating sessions and he wanted to be able to start the ascent without the derailment. 

Flat cars and light weight (i.e., MRC) cars are the first to tip inward as a consist starts up on a grade. (In real life, trains that stop on an ascending mountain curved grade, may need to back down to a less steep tangent track, stop and then move forward again up the grade.)  Of course heavier cars can hold the track but then the locomotive needs more momentum and traction for the grade.

Model train superelevated track without grade changes or S curves normally will handle the higher speeds as stated in the AF promotion.  AF cars were all fairly heavy cars, too, so it makes sense that the superelevation worked with AF track.  Add a 3-4 percent grade and 

[overlandflyer]

KRM

... there must have been someone at American Flyer in 1934 to 36 that thought a pitch on the curved rails was a good thing. ...

 Am I nuts?????  

even earlier than that, from the 1927 catalog (the earliest one i have)...

"American Flyer Track is scientifically banked higher on the outside rail to prevent the train from jumping the track while traveling at high speeds."

changed slightly, and by 1936...

"IT'S BANKED -- To permit even higher speeds, it's scientifically banked higher on the outside rails.  This is an exclusive American Flyer feature and is essential for the proper operation of streamline trains."

cheers...gary

[KRM]

Guys,

As I said in my first post:

 I have some Pre-war American Flyer track that has a pitch.

Here is why I asked in the first place,,,, there must have been someone at American Flyer in 1934 to 36 that thought a pitch on the curved rails was a good thing. Maybe check with Northwoods Flyer to se if I am wrong. You tell me?

 Am I nuts?????  

 

 

 

 

 

 

[jonadel]

My experience with the raised track idea has all been good and I haven't had a train fly off in 13 years, knocking on wood.  I haven't used the idea of slanting the track, it's all flat but I do like the looks of the slight camber.  The one thing I did was when there was a curve on the top track it neither went down or up, it was flat and I only used straights for raising or lowering.

On the engines where the traction tires have worn off if I'm going slow often times the engine wheels will start spinning when going up and they need a little assist, especially if I'm pulling a long consist.  At a decent speed they climb right up with no problem.

I really enjoy having a second level, it sure adds another dimension for the eyes plus it just looks good

[KRM]

Well so far besides the calculations and such my only truth is in running. I have driven eight different trains over the raised area and none of them had a consist of less than 9 cars counting tenders and cabooses and the most was 14. None experienced any problems with the Cant or superelevation. The trains look very nice as they roll over the curves as the superelevation changes from pitch to level and back.

Only one had a problem with the grade incline and that was wheel slippage with a post-war 681 pulling 12 heavy post war cars. I ran Lionel post-war 681,218,202 ABA set, MPC, DT&I 8111, new Haven F3 AB set, Modern NS 18207 lashed to a 18213, CSX 18214 alone. Two K-Line lashed up ALCO S2 switchers and a RMT Bang. One thing I will say is the engineer needs to be driving the trains. I also do not have any added lockons and it could use at least one.

Will keep at it.

watch?v=UleH4M4wAoM

 

Going the other way,

watch?v=T74vzVZZoI4&feature=youtu.be

[overlandflyer]

lionelsoni

Unfortunately, on our unrealistically sharp toy-train curves, the forces pulling cars to the inside of the curve usually overwhelm any centrifugal problem.  So anyone considering superelevation should be aware that it may create or make an existing problem worse.

as weird as this sounds, i can attest to its truth.  i discovered this once when making a helix display with a friend.  slightly raising the inside rail on the smaller diameter curve actually helped the train stay on the track better.  our initial attempt at super elevation constantly resulted in the train being pulled off to the infield.

[runtime]

Bob:

On my layout, unintended speeding does sometimes happen.

I  had  a steamer barrel roll of the outside of an 031 curve prior to superelevating it, but not since. I have not encountered any string lining with up to 15 or so carefully chosen cars. 

I concur with those who think a little superelevation is the lesser of the two potential problems, as the barrel roll broke a running light of the steamer.

For what it's worth,

runtime

[KRM]

Buckeye,

I was testing with 10 to 13 car consist counting the engines,, the longest I can fit into the switchyard and see no sign of them wanting to collapse to the inside. And it they collapse the inside will be way better than the outside 40" down. The whole thing was loose and just sitting on the table. Today I screwed the risers down to the table and have made hardboard decking and I will try it again. Like Frank, I to like the way it looks but it has to work. I still have the level risers so I can change it if need be. I have pulled 25 cars and two engines around the Marx 34" R curve and not had them stringline 72 and 54 should be a cake walk. We shall see. I will let you know.

Looking back the 5 degree pitch may be a bit too much. 3 may of been better.

[Frank53]

But the raised outer rail just looks cool. I rarely run more than eight or so cars so can't say I have had much of a problem with cars collapsing to the inside of a curve. My layout is too small for much more.

[Buckeye Riveter]

lionelsoni

The superelevation needed to balance the centripetal forces varies as the square of the velocity.  So superelevation is designed to balance the forces for a particular speed.  For faster or slower trains, the forces are unbalanced.  The maximum unbalanced superelevation allowed is usually 3 inches (1/16 inch).  So a track that must accommodate very slow trains is not allowed to be superelevated more than 3 inches.   The greatest superelevation allowed in the US is 6 inches (the difference in height between the outside rails), or 1/8 inch in 1/48 scale, but any such track superelevated more than 3 inches must have a minimum as well as a maximum speed restriction.

Unfortunately, on our unrealistically sharp toy-train curves, the forces pulling cars to the inside of the curve usually overwhelm any centrifugal problem.  So anyone considering superelevation should be aware that it may create or make an existing problem worse.

Well said.  I keep my curves as flat as possible and sometimes have had lighter weight cars pulled off the track as the toy-train ascends the grade if I have too many cars trailing.   Check out this on-line book for interesting details about how trains hit the dirt.

Train Wreck: The Forensics of Rail Disasters

By: George Bibel

[KRM]

LV,

I should say that these are all on 72" but two 54" curve sections with a max height of 3.25" on the straight 42" section that is level, so I am not too worried about stringlining on them even with the pitch when I have a 34" curve on the same loop. I will test run it for some time before deciding and covering it.

Thanks. Bob.

[Lehigh Valley 2089]

Looks sharp, though I would take some caution for the reason that Lionel Soni mentioned. If it were me, I would just lower the speed of the curve.

[lionelsoni]

The superelevation needed to balance the centripetal forces varies as the square of the velocity.  So superelevation is designed to balance the forces for a particular speed.  For faster or slower trains, the forces are unbalanced.  The maximum unbalanced superelevation allowed is usually 3 inches (1/16 inch).  So a track that must accommodate very slow trains is not allowed to be superelevated more than 3 inches.   The greatest superelevation allowed in the US is 6 inches (the difference in height between the outside rails), or 1/8 inch in 1/48 scale, but any such track superelevated more than 3 inches must have a minimum as well as a maximum speed restriction.

Unfortunately, on our unrealistically sharp toy-train curves, the forces pulling cars to the inside of the curve usually overwhelm any centrifugal problem.  So anyone considering superelevation should be aware that it may create or make an existing problem worse.

[Frank53]

I place a 1/16" wood riser under each tie on the outside:

[rtraincollector]

Looks good not a bad idea at allgives you the chance to do higher speeds on the flyover

[KRM]

RT, Seems no one has ever seen this or they are all watching some game tonight.    Here is what I did. I cut some at 3 degrees and some at 5 degrees, I went with a combination of 3 moving to 5 here is the difference. I like this much better.

 I also have Lionel Pre-war track that has a angle cut into them.

Before the angle cut.

 

 

After the angle cut.

 

 

[rtraincollector]

Back during prewar Lionel made some track that the out side rails where higher than the inner rails but I believe it was only standard gauge.

[KRM]

I am installing a riser to raise the outside track on my layout addition. I noticed on some pre-war American Flyer O gauge track the curves have a pitch to help offset high-siding when going through the curves. I am thinking that would be a good idea on the risers I am using under the curve sections of track. Anyone know how many degrees of pitch it should be?? Suggestions??? 

I don’t mind the train being level on the straight track but don’t like it level on the curves.

Thanks, Kev.