Suggestions for making hidden track bulletproof?

[defor]

What's the bet way to ensure perfect track alignment in order to eliminate all but the worst derailings in hidden track sections?

In both of my current project layouts I have simplified hidden tracks concealing a back to front passage (or loop) to give the appearance of trains leaving the layout, then arriving later.

I've seen references to soldering unitrack together-is this advised?

I assume one would solder, file down the track and solder joint to a flush surface, etc.

 

Alternately, is conversion to something like a long run of flex track for the hidden sections possibly a better option? I'm thinking this could minimize the number of joiners needed.

 

[gavino200]

Try very slight filing of the rail ends. Then note any place where any car derails and switch out the joiners. Also, use rerailer tracks liberally. They’re going to be hidden anyway.

 

lastly make sure you have an easy way to access your hidden track.

[cteno4]

Gavin is spot on. I think careful filing of unitrak can get you really good w.o the hassle of soldering and cleaning up well. Flex will work but joints on curves require a lot of careful welding and support to stay in a continuous curve and in gauge.

 

most important do have access! Murphy’s law of tunnels, if no access trains will derail in perfect track will cause derailments in there.

 

jeff

[bill937ca]

1 hour ago, cteno4 said:

most important do have access! Murphy’s law of tunnels, if no access trains will derail in perfect track will cause derailments in there.

 

jeff

 

If you have no access how can you detect deficiencies?  

[defor]

lol-

ok some great comments here... basically the core issue i'm fighting with is that the hidden track on the 1'x7' layout passes right under my main freight yard- I have two options for access at present, and neither are great :(.

1. Removable access:
   I can definitely build some kind of removable section, but how to keep the cut tracks aligned when the removable section is pulled?
   Also if i have a yard full of trains, I'll have to manually displace them during the removal...
2. Mushroom? style access:
   The hidden track technically can be moved to the very edges of the bottom layer such that it can be seen on the front, right side, and back, but the corner support triangles (if left in) will make for rather deep recesses, and it will be a bit tricky to access anything on them.
   Also, the back of the whole shebang is inaccessible without moving the entire layout off the shelf it's sized to fit.

I was hoping there was some magic to running trains without access except in extreme circumstances, but it sounds like derails happen regardless, and at any time...

 

7 hours ago, gavino200 said:

Try very slight filing of the rail ends. Then note any place where any car derails and switch out the joiners. Also, use rerailer tracks liberally.

Two questions about this:

• So you're not advocating soldering the entire assembly together?
  I ask because the ends of joined track seem capable of moving relative to each other even when glued down.
• The question was asked elsewhere, but Kato unitrack rerailer segments seem .... useless? is there some magic trick to getting them to rerail bogies with an axle that's jumped the track?

[gavino200]

1 hour ago, defor said:

Two questions about this:

• So you're not advocating soldering the entire assembly together?
  I ask because the ends of joined track seem capable of moving relative to each other even when glued down.
• The question was asked elsewhere, but Kato unitrack rerailer segments seem .... useless? is there some magic trick to getting them to rerail bogies with an axle that's jumped the track?

 

I have no experience with soldering rails. 

 

I'm not sure what you mean by "the ends of joined track seem capable of moving relative to each other even when glued down." Do you mean that there can be a micro step-off between rail ends? I agree. That's why filing can help. Also some micro bending to get rails lined up perfectly can be helpful. Emphasis on "micro". Btw, if you file, file so little that you're almost not filing at all. Really, only a couple of light rubs with the file. Too much and you create an old-fashioned 'clickety-clack' as the trains pass over it. 

 

I swear by the re-railers. So does Kato, I think. Their display track at the Hobby center has a lot of them. 

 

I have my hidden track tuned this way so that nothing ever derails on it. Mine is circular, so I have re-railers only on the entrance and exit. But I'm still planning on having everything lift out.

 

Test ALL trains, and all carriages on all tracks in all directions at all speeds. Many, many times. Some problems are very idiosyncratic and affect only specific trains in particular directions.

Edited July 7, 2018 by gavino200

[cteno4]

The retailers do work a lot of the time and are handy near very prone derailment spots like points. Have you found them not to work formyou?

 

soldering does work but is a lot of work and not easily reversible.

 

i would suggest mocking this all up with unitrak and playing with it for a while. You can hot glue or screw down track to try it more solid for a while then too. For the most part I’ve found points to be the biggest place derailments happen or odd stuff like S curves that can make odd pressures on some car/bogie/wheel alignments. Tune some and at last ditch go to soldering.

 

gavin is spot on derailments tend to fall into three categories: 

 

- bad track section like a point or bad rail joint

- bad train issue to a train or car and your track configuration

- random, unrepeatable events, these happen once and a while

 

jeff

[gavino200]

1 minute ago, cteno4 said:

S curves

 

S curves are the Devil!

[cteno4]

Yep, filling in straights between the curves helps butnthe lenght is very train dependent... points with sidings and ladders naturally can create S curves and then you have the blades and frogs that can also mess with the flanges...

 

jeff

[railsquid]

34 minutes ago, defor said:

I was hoping there was some magic to running trains without access except in extreme circumstances, but it sounds like derails happen regardless, and at any time...

 

 

Murphy's Law will definitely apply no matter how well designed the track/tunnels are.

Is there any way you could create access from below the layout? I can't envisage how your layout is set up so it might not be possible.
 

Also, how will you clean the tracks?

[bill937ca]

S curves also cause pressure on couplers that may lead to derailments.   With an S curve you need a straight equal to your longest piece of rolling stock between the two curves. This is basic railroad design. Speed restrictions are also a good idea.

Edited July 7, 2018 by bill937ca

[kvp]

One reason for dreailments with longer trains is weight and couplers. A train could derail without warning on a perfectly straight and level piece of flex track when the motor unit decides to have a hickup and stop or slow down for a few milliseconds. If it has traction tires, the sudden stop could create a wave of stress through the train and if there is enough mass behind the motor, some cars could lift up a bit, which could be enough for some wheels to jump the rails. Works the same way on the prototype if the front side of the train brakes too hard and the pressure drop doesn't propagate fast enough. (mostly with older freight stock and no mid train helpers or a fred)

 

The only good solution is to have access. One way is to make the top yard removable. The other is to have side access or the lazy one to have bottom access, aka. a cutout next to the bottom tracks. This would allow you to get on your knees, crawl under the layout, remove the anti fall down barriers and fish out any derailed trains and clean the track. Personally i think making the yard lift out is harder but makes maintenance easier.

[nickhp]

I am guilty of soldering Kato track joins.  Unfortunately for defor, I did it because I am running B Trains on it like he intends to do, and with an unpowered car up front (I always put the motor chassis in the second car of any train over 2 cars in length), being pushed vs. pulled, uneven track joins are a bigger issue due to the light weight of B Trains.  I noticed unijoiners do not do a good job of aligning rail horizontally or vertically, which is why I soldered all my joins after carefully adjusting each track join individually. 

 

I would say my attention to detail is borderline obsessive, but at the same time I have had a total of no derailments in the many tens (if not hundreds) of hours of use the layouts have gotten running B Trains. 

 

Nick

[gavino200]

1 hour ago, nickhp said:

I am guilty of soldering Kato track joins.  Unfortunately for defor, I did it because I am running B Trains on it like he intends to do, and with an unpowered car up front (I always put the motor chassis in the second car of any train over 2 cars in length), being pushed vs. pulled, uneven track joins are a bigger issue due to the light weight of B Trains.  I noticed unijoiners do not do a good job of aligning rail horizontally or vertically, which is why I soldered all my joins after carefully adjusting each track join individually. 

 

I would say my attention to detail is borderline obsessive, but at the same time I have had a total of no derailments in the many tens (if not hundreds) of hours of use the layouts have gotten running B Trains. 

 

Nick

 

Can you give a short description of how you do it?

[nickhp]

You can see an example of soldered joint here:

 

 

Basically, I join up the trackwork as a complete assembly and glue it to the layout base after making sure there are no big gaps or issues.  I then focus on each track join at a time and initially try to get the track join smooth by simply pressing on the rail on the side of the join that is slightly too high.  My check is to run my finger over the join in both directions and see if I can feel the join.  If I am not sure I use my fingernail to see if it "catches" on the join in either direction.  If this works, I solder the OUTSIDE of the joiner and rail as you can see above.  I check again after soldering to ensure the rails are flush.

Sometimes the track doesn't want to cooperate.  If that happens, I get it as good as I can and then solder the join.  I then use a flat blade screwdriver so the tip is across the join along the rail, touching both sides of the join.  While applying a little bit of pressure to the top of the rail and *trying* to keep the screwdriver blade as flat as I can, I apply heat to the solder until it melts, the rails line up with the screwdriver blade and then I let go of the soldering iron until the solder sets and then remove pressure from the screwdriver and check the alignment again.  It's a bit of trial and error.  The key is not to apply heat for very long so you don't melt the plastic stuff around, just long enough for the solder to "give" and allow the rails to move.

 

BTW, I do one side of the track at a time, you won't get both rails in one go, obviously!  I will usually do a few joins on one side before changing to the other rail and working to the same point on the other side of the track.

 

Let me know if you need me to explain further.

 

Nick

 

 

Edited July 8, 2018 by nickhp

[cteno4]

Track heatsink can help as well. Just a small block of aluminum with rail slots cut into it to fit over the track. Either two of these, one just outside the joint to give a gap to solder in or there is one piece design that fits over the whole joint and has two little sections routed out at the joint to give you a space to solder. Helps the rail from heating up the track and loosing the “spike” track holders. A lot of flex track is vulnerable to melting the spikes just past joints if you are not super fast. Unitrak luckily is slightly embedded into the ties so less vulnerable but track soldering takes some practice to get it done well and fast! 

 

Jeff

[nickhp]

The reason for using the screwdriver blade is to help align the track vertically once the solder melts, not to act as a heatsink, even though it does act as a heatsink anyway.

[cteno4]

Yep I realized that, I was just adding the heatsink idea as it’s a common issue folks can have in doing the initial solders on track joints. Helps if you heat the track a bit to long/much. I like the screwdriver idea as unijoiners don’t always hold track vertically quite as well and seem to get worn out some more in that direction usually than laterally. I’ve usually found the vertical bump to be the big derailer. On the club layout we have shimmed bad joints if we don’t want to tear up sections to put in new joiners. Usually works but with time they can go out again immsure by the larger modules getting some torsion with moving. Newer modules are stiffer so hoping not as much an issue. Works on module joints as well.

 

one trick I found way way back when soldering flex track was I would pull the rail end out if I could and tin it. Then made the fusion much faster and generally solder will not leave a big blob but glow across the joint well. At times I had to hit it with the file to grove any tinned but to make the rail joiner fit over. 

 

Also quick rub of the end bits with a firm brass contact cleaner helps make some tiny scratches which helps the solder grab faster and removes any surface impurities that can delay the solder adhering or burn and oxidize and prevent good solder joint.

 

Also tiny dab of flux helps even if using rosin core to make things start to stick faster and also make it flow into the jointer much faster (that gets you the real weld). If it’s acid based flux Best to smear a dab of baking soda paste on after wards and wipe it off with a damp cloth.

 

just little things to make the solder go as fast as possible.

 

cheers

 

jeff

[nickhp]

BTW, all my comments relate to Kato unitrack, I found Tomix Finetrack to be really difficult to solder...

[gavino200]

51 minutes ago, nickhp said:

You can see an example of soldered joint here:

 

 

 

Basically, I join up the trackwork as a complete assembly and glue it to the layout base after making sure there are no big gaps or issues.  I then focus on each track join at a time and initially try to get the track join smooth by simply pressing on the rail on the side of the join that is slightly too high.  My check is to run my finger over the join in both directions and see if I can feel the join.  If I am not sure I use my fingernail to see if it "catches" on the join in either direction.  If this works, I solder the OUTSIDE of the joiner and rail as you can see above.  I check again after soldering to ensure the rails are flush.

Sometimes the track doesn't want to cooperate.  If that happens, I get it as good as I can and then solder the join.  I then use a flat blade screwdriver so the tip is across the join along the rail, touching both sides of the join.  While applying a little bit of pressure to the top of the rail and *trying* to keep the screwdriver blade as flat as I can, I apply heat to the solder until it melts, the rails line up with the screwdriver blade and then I let go of the soldering iron until the solder sets and then remove pressure from the screwdriver and check the alignment again.  It's a bit of trial and error.  The key is not to apply heat for very long so you don't melt the plastic stuff around, just long enough for the solder to "give" and allow the rails to move.

 

BTW, I do one side of the track at a time, you won't get both rails in one go, obviously!  I will usually do a few joins on one side before changing to the other rail and working to the same point on the other side of the track.

 

Let me know if you need me to explain further.

 

Nick

 

 

 

 

Great description! Thanks!!