Rerailers for LH and RH crossing

[Hayashi]

Should I place rerailers before and after Kato crossings (20-300, 20-301)?

 

I am considering a freight loop that would cross a commuter spur leading to a commuter yard. Yes, I know there is a potential for a catastrophic crash if I run the freight while the commuter passes into the yard, but it's part of the compromises in building a layout without unlimited space. My bad if I let that happen. Because the freight could be running at a Japanese freight express speeds, I want to ensure I don't derail passing through the points. It is on a long straight section so the train should be lined up properly, but I don't know how well trains pass through the crossings. No problem? Possible problem? Big problem?

Edited December 19, 2018 by cteno4
Fix title after merge

[katoftw]

No problem. No difference between freight and commuter through turnouts.

[cteno4]

The 30 degree crossings have never given us any problems on any of our layouts.

 

The 90 degree are a bit more finicky I think due to the flangeways having more of a bump and they don’t like having curves coming right off them. 

 

All that being said always good to put rerailers in where possible. Wish they had pop in ones like atlas track. Maybe something to try to 3D print. Or maybe ones that were like guide rails that could get easily snapped onto unitrak.

 

cheers

 

jeff

[Hayashi]

Thanks. I agree regarding pop-ins. I had one in the layout from my youth. I saved a lot of buildings and US rolling stock, but I'm sure I didn't save the rerailer before having to tear the whole layout apart. Does Atlas still make those? I'd like to place them before and after bridges and turnouts. 

 

Is the sleeper spacing on Atlas the same as Kato (I suspect not). If they were, sanding down the tabs that fit between Atlas sleepers and then CA gluing them in place might work. Or, how about sanding the tabs off completely and CA gluing them. Has anyone tried that? They're a lot less obtrusive looking than Kato's.

[cteno4]

I’ll dig around in a very old box of atlas track I have but I fear they won’t line up with the unitrak well. The atlas track has a lot of depth between ties (without ballast) that you don’t have on unitrak. On unitrak they would need to be glued in or a very strong pressure fit on the little bit of exposed ties. May be enough just using the spike heads as I find 1/4” 060 stryene strip nestles in just right between the strips for road for streetcar 25mm Ttrak modules. I’ll try and sand a chunk into a rerailer shape to see how well it holds w.o glue. 

 

jeff

[kvp]

Generally the safest bet is to run from the frog side, so the normal running direction is from the trail of turnout, not against the blades from the point side.

 

For crossings, most of them have guard rails, but adding a rerailer behind them should be ok.

 

Personally i think if you have to depend on rerailers, you are doing something wrong from a modelling standpoint. The prototype doesn't use them as part of standard operations...

[cteno4]

Apples and oranges, models are not the prototypes. Physics is different, manufacturing quality, track differences. Even on the best built layouts derailments are waaaay more common than on the prototypes.

 

jeff

[kvp]

2 hours ago, cteno4 said:

Apples and oranges, models are not the prototypes. Physics is different, manufacturing quality, track differences. Even on the best built layouts derailments are waaaay more common than on the prototypes.

Yes, but most of them is due to operator error or shunting mishaps. But when you have a layout that absolutely needs rerailers at certain points because you have a >= 10% chance of derailing a train when you go past it, then it's usually either bad layout design, overspeed or badly maintained rolling stock.

 

Bad design includes not separated canted S curves, turnout blade points just at the exit of a curve, a high speed section with turnouts in them (or at least ones that are not normally passed from the trailing direction) Overspeed is trivial, going too fast across a low speed crossing or turnout is always a bad idea, while proper maintenance means freely rotating bogies and wheels with the proper gauge set and reliable couplers and motors.

 

If you know and respect the limitations of the models and the track, then it's reasonable to expect fairly reliable operation without frequent derailments. Clever layout designs could eliminate the rerailers. For example, if the crossing pieces are between at least one car long straight tracks, then it should be derailment free, but still it won't be passable at full line speed. (the diverging and crossing direction is slower speed already because of the turnout, but question was mainly about the straight trough direction)

[cteno4]

10% of the time means there is a big problem, it’s when it’s more random and infrequent that is the usual problem that rerailers really help on.

 

Even if you do good design you will still get the very annoying and frustrating to disgnose derailments from just the random chaos of the limitations of small models. I’ve dealt with this for years on the club layouts, first finding specific permutations that cause issues, then trying to slowly suss out the more random ones to see if they have some very odd permutation that causes them. It’s a very slow and tedious task.

 

Design limitations with your track, equipment, design likes, and operation style are something that you learn over time and can’t solve starting out. Yes you can get a lot advice from others, but in the end it’s a long learning process and rerailers can help reduce the frustration in the mean time. Some get into eliminating all the Derailment causes, but this can take a lot of time and energy many just don’t have or just don’t enjoy doing. 

 

Japanese trains also come in a very wide permutation of coupler types, diaphragms, truck geometries, etc that the same track plan may work great for most trains but has issues for a few. Designing out all potential derailments with layout and equipment can be an unending task and can lead to a very boring layout design and roster.

 

So adding derailers in critical areas csn really help lower frustration and frustration is one of the big things that can kill the hobby for many. We have always added them in around areas that may have issues in our layouts and the. We can remove them if not needed later or we fix any issues, but always left some in in critical areas just to be safe on the club layouts. Since it’s a mobile layout we module track joints and module flexing in transport that can keep throwing variables into the derailment equation.

 

cheers

 

jeff

[kvp]

Jeff, could you list locations where you recommend to have rerailers? The only obvious one i can think of is the exit point of fiddle yards.

[cteno4]

On viaduct Shinkansen lines we always put them just inside the points in station passing sidings and also in the center of our Long station. Middle one gets a few strays sometimes that the end ones miss. Usually our viaduct derailments are at the points or s curves of the sidings. They are rare but rerailers will help undo a lot of them and save a crash. Usually they are now just an odd permutation of equipment, module alignment (never the same each time you set up the layout and can change while setup as the whole layout flexes some with bumping and such), bumping of layout, etc.

 

on the ground slower tracks usually near points if near curves and near s curves. Usually at the ends or center of a passing siding. The 90 degree crossing on our really old layout that was near a curve. 

 

Or any place you notice a derailment happening until you can find and correct the cause.

 

track alignment can also do it with wheels taking a hard thump. Pushing on the rails can sometimes correct this, sometimes the unijoiner needs to get changed out. On our mobile layout these can pop up in the middle of a module later due to stress on rails from module flexing and joining and unjoining modules. Usually fiddling with the screws and adding a shim of cardstock fixes it.

 

never found them to cause harm, but only rerail many derailments that could have cause bigger problems. Of course we work to find causes of derailments but with the huge range of trains we run and the variables of a mobile layout it’s a never ending job and some of the random ones you just can never catch what’s causing it if it happens once every couple of hours! Sometimes you can drag a detail wheel for 5’ before it totally derails so it can be hard to localize where it happened.

 

points to can get cranky, throwing fine for a long time then getting a bit erratic for a while. I try to blow them out and throw the point back and forth to clear any bit of schmutz that may be hanging it a little and check the blade to see if loose or somehow out of alignment. Even had a bit of grit get caustic in a point flangway that the flange was bumping on and causing derailments. 

 

jeff

[Hayashi]

My goal is to eliminate all S-curves, make sure all rolling stock gauges properly, and try to Murphy-proof as much as possible. I also have experience with an errant piece of ballast or dust crumb falling in exactly the wrong place on an old n-scale layout. Unless I run a Doctor Yellow with a macro camera before each run I think it's impossible to 100% eliminate possible derailments. Even on my old G-gauge garden railroad I would have derailments. And those 15-pound locos could nearly run over a squirrel's tail and still not derail. But, it still happened.

 

My plans to create trouble-free operations are:

 

1. At least 124mm straight viaducts before entering a Shinkansen station or Suburban station. Currently, I am limiting my layout size to approx 12' with an 8-car station (i.e., 7x 248mm in the through section). That limits me to 124mm straights at both ends, but hopefully rerailers will assist (see Item 2 below).

2. Rerailers at the Suburban station entrances. Does anyone know if a rerailer can replace the 124mm track in a double viaduct? If so, I would also add rerailers to the Shinhansen station entrances.

3. #6 turnouts for all station sidings.

4. Rerailers before and after double crossovers. I only have two. Does anyone know if a double crossover could be retrofitted to a double viaduct (obviously it requires two viaducts)?

5. Eliminate all S-curves with at least 186mm between curves. I have only one spot currently in my design with a 124mm between the S-curves, but I'll place a rerailer there to help with alignment. Both entrance and exit curves in this one case are 315-45s on the freight mainline.

6. If possible, have a rerailer at the frog end of a turnout on main freight line. 

7. I can't control train direction on the freight line since it will run in both directions and is a single line. Thus, trains will enter both point ends and frog ends. That's life.

 

Although this may sound like a lot of rerailers, total count is still relatively low considering the amount of track I have planned--a double Shinkansen loop, a double commuter loop, a single freight loop. The rerailers, thankfully, are mostly in areas where they will either act as road crossings or a somewhat screened by buildings or other scenery.

[kvp]

If you have canted curves and shinkansen then having at least 16 cm of straight would be a good idea or some trains will have a 100% derailment probability. Also canted and S curve derailments are usually twist off events, when the bogie is lifted clear off the tracks and having a rerailer doesn't really matter as the wheels will float over it.

[cteno4]

3 hours ago, Hayashi said:

 

1. At least 124mm straight viaducts before entering a Shinkansen station or Suburban station. Currently, I am limiting my layout size to approx 12' with an 8-car station (i.e., 7x 248mm in the through section). That limits me to 124mm straights at both ends, but hopefully rerailers will assist (see Item 2 below).

Great this really helps a lot. Also backing your curved platform ends back 0.5-1” can get rid of a few random ones when running out onto the passing tracks fast

3 hours ago, Hayashi said:

2. Rerailers at the Suburban station entrances. Does anyone know if a rerailer can replace the 124mm track in a double viaduct? If so, I would also add rerailers to the Shinhansen station entrances.

Yes you could replace in the viaduct track, but I don’t think it will help a huge amount as usually derails at the point but at times you can be dragging a wheel from a problem in the curve

3 hours ago, Hayashi said:

3. #6 turnouts for all station sidings.

Generally a lot safer than #4 overall but you can put the effort into making #4 much cleaner if you want

3 hours ago, Hayashi said:

4. Rerailers before and after double crossovers. I only have two. Does anyone know if a double crossover could be retrofitted to a double viaduct (obviously it requires two viaducts)?

Yes these too can get a little cranky and have a lot of places bits of schmutz get stuck. I’ve found them with hairs and bits of thread I think from track cleaning with rags and folks don’t scrub hard on the double crossover (all the blades and frogs make it hard) so I thin stuff kind of gets swept there and left and then lots of things to hang onto it in all the flangeway bits. Yes you can hold the viaduct bases together with the S jointers and lay in regular track to do a double crossover. We usually do them in the middle of the station.

3 hours ago, Hayashi said:

5. Eliminate all S-curves with at least 186mm between curves. I have only one spot currently in my design with a 124mm between the S-curves, but I'll place a rerailer there to help with alignment. Both entrance and exit curves in this one case are 315-45s on the freight mainline.

Good even a tiny separation helps the stresses on the trucks

3 hours ago, Hayashi said:

6. If possible, have a rerailer at the frog end of a turnout on main freight line. 

7. I can't control train direction on the freight line since it will run in both directions and is a single line. Thus, trains will enter both point ends and frog ends. That's life.

 

Although this may sound like a lot of rerailers, total count is still relatively low considering the amount of track I have planned--a double Shinkansen loop, a double commuter loop, a single freight loop. The rerailers, thankfully, are mostly in areas where they will either act as road crossings or a somewhat screened by buildings or other scenery.

 

You can always pull them or experiment with them before you nail things down to see what ones are the most valuable. Things do change a little when you affix your track down though and before you ballast or really hard set your tracks it’s best to test and fiddle. This is why I like doing screws from the top as they allow you to loosen and play with things easily and reset the track (drill a new hole next to the screw/nail support and relocate track a tiny bit if needed. Most of the time I’ve found it was one track needed to go up or down a tad on the end and loosening the screw and shimming or cinching it down did the trick. Keeping your geometry and alignment good while attatching is hard, I’ve used pins to hold it in place and just went around and replaced them with screws. I think on our new layout here we may try making some custom pins with a bent over spike head sort of to try to do a temp affix of the track but allow trains to run to test some and then once sure good replace with screws.

 

cheers

 

jeff

[Hayashi]

Jeff, is there a reason you usually place your double crossovers in the middle of a station? There aren't any clearance issues with trains hitting the platforms?

[cteno4]

Hayashi,

 

its just the most convient place to put them and near reach to operate them on the layouts we have done. No issues with platform rubbing. Also let’s us put the crossover in anvery straight section and easily have rerailers around it for extra protection.

 

Unfortunately we bring our shinkansens in from the yard onto the outside passing track in the station (most convenient place to put the entry point and save space) so if you want to move trains between the inner and outer tracks then to the yard you do need to go around the layout and then have the outer passing siding open.

 

the end platform rubbing is usually from higher speeds where cars are under tension more usually and get canted some and can bump the platform end and then that sets up an oscillation that can cause the derailment. It took a lot of watching to find this happening years ago on our first layout. Once I shortened the platforms a tad to bring in the ends it solved almost all of these sporadic derailments and the ones left were mostly equipment specific. This was running trains thru the passing sidings at speed, so it’s a bit of an s curve but works fine if you work out the kinks! We do this to quickly alternate trains on the lines when we don’t want to take the time to exchange trains into the yard which takes a few minutes and many public viewers get bored with this and can quickly move on...

 

cheers

 

jeff

[Hayashi]

Jeff, 

 

Makes sense. My joint shinkansen/commuter yard (not prototypical, obviously) will feed into my inside commuter station passing track. Since my total layout length is just 12' feet, I'll put my double crossover opposite the commuter station and behind the shinkansen station. That will keep the rerailers a bit hidden too. I plan to use the shortened 23-105 (for shinkansen) and 23-120 (for commuter) platforms based on your advice to eliminate potential platform rubbing. Thanks.

[cteno4]

I actually just custom shortened a straight platform to bring the ends a tad. We have the last couple of platforms with out roofs so folks can see the trains so easy to shorten them.

 

on our oldest layout we had a second small Shinkansen station without passing tracks and we had the crossover there, but it was a bit out of sight so you couldn’t always see it to make sure all the points were set right. 

 

In the big station with passing tracks and platforms and roofs and roofs the rerailer and crossover are pretty hidden.

 

cheers,

 

jeff

[VentureForth]

I DO realize I'm starting a bunch of seemingly ridiculous threads about menial stuff.  But, hey, that's me.

 

So, in the My Plan set I haven't opened yet, I noticed that there is a rerailer S140 track included.

 

Is there a strategic place any of y'all place rerailers along your track?Insert other media

[VJM]

I didn't place any rerailers on my layout (nor did I have any spots that needed them).

 

I would suggest you perform some track tests and see if there are any spots that may possibly have a derailment, eg after S curves and possibly use it to assist a train back onto the track.  Another good spot would possibly be in a tunnel where access may be limited.

[cteno4]

4 hours ago, VentureForth said:

I DO realize I'm starting a bunch of seemingly ridiculous threads about menial stuff.  But, hey, that's me.

 

Venture,

 

no worries the devil is nin the menial a lot of the time. We did have a lot of retailers talk in an existing thread here so I moved your new one here to keep all the retailer stuff together. We like to try to keep similar content growing in one thread rather than end up with multiple threads when possible.

 

good track work and layout planning can avoid need of rerailers, but many times you have to compromise and then rerailers help! A lot of what I expressed above is from experience on our club layout in the last 14 years, but those were/are temporary setups or sectional travel layouts which make issues that retailers help with. Folks like vjm with a good solid and well planned layout don’t need them much at all. Really based on your reality and seeing if they help if you start to find problems in your layout and can’t fix the cause of them.

 

jeff