The Transcontinental PRR

[eric220]

Well, I just checked MBK's stock. They have all the 20" sectional that I'd need, and enough 18.75" for two loops. That's the full turn packs, so six pieces per 180 turn. That leaves six packs of 18.75" that I'd have to scare up. Not quite as impossible a task as I thought.

I'm warming to the idea of sectional, but I'm still not convinced that a subtle and hard to fix snag in a sectional setup isn't far more dangerous than superelevation.

[packers#1]

Really the main thing to keep in mind with sectional track is to take your time and and make sure the rails line up. If you're concerned with melting track, just cut the little "ties" off from around the connection area since they don't support the track anyways

[CodyO]

Eric with sectional you'll lose the ability to remove and replace tracks quickly
Via kato unitrack
With unitrack you simply stand in the middle of the helix and snap the track together and push it down the loop
And removal is just as easy

I'm pushing this cause though you may want smaller rails your helix is the Keystone in your design and you need it to act reliable so that you can take any train up and down the helix without a hiccup

I've even been able to use helpers on my trains going up

Please don't make yourself prone to kinks and expansion joints and headaches and having to run only certain trains up "that damn helix"

[DKS]

Eric with sectional you'll lose the ability to remove and replace tracks quickly

Splain why he'd need to remove and replace track on a (presumably) permanent helix...

Please don't make yourself prone to kinks and expansion joints and headaches and having to run only certain trains up "that damn helix"

Spoken by a true hard-core Unitrack member. Honestly, since the rest of Eric's layout is C55, what restriction would there be by using sectional C55? As for "kinks and expansion joints and headaches," I've never had any, and I've used flex, sectional, and Unitrack. Maybe I'm just lucky.

And soldering isn't awfully hard. Just practice first. There are plenty of tips in Railwire on soldering track successfully.

[ChrisKLAS]

Well, I just checked MBK's stock. They have all the 20" sectional that I'd need, and enough 18.75" for two loops. That's the full turn packs, so six pieces per 180 turn. That leaves six packs of 18.75" that I'd have to scare up. Not quite as impossible a task as I thought.

I'm warming to the idea of sectional, but I'm still not convinced that a subtle and hard to fix snag in a sectional setup isn't far more dangerous than superelevation.

I used the 20 and 20.25" sectional pieces for my 5.5 turn helix and couldn't be happier. A 60 car train with six motors goes up with ease. Of course, track joints were carefully aligned, soldered, and feeders dropped every 1/3 turn.

[glakedylan]

fwiw
i have used Atlas code 55 sectional track
actually a PRR mainline 4 track 17.5" - 21.25"
had no issues at all
went together easy, stayed together
now the code 55 flex did expand and kink, needing a little shortening before relaying
but sectional track was excellent and will be using it again

that said
i have an Ashlin helix designed for 15" - 16.299" kato superelevated concrete tie track
works flawlessly and the Kato track just slides into place

the biggest challenge therein is the joint to the code 55 which if done well is not an issue

one might ask if the super-elevation helps the train climb the helix? i would think it helps.

regardless,

either will serve you very very well!

sincerely
Gary

[CodyO]

Splain why he'd need to remove and replace track on a (presumably) permanent helix...


Spoken by a true hard-core Unitrack member. Honestly, since the rest of Eric's layout is C55, what restriction would there be by using sectional C55? As for "kinks and expansion joints and headaches," I've never had any, and I've used flex, sectional, and Unitrack. Maybe I'm just lucky.

And soldering isn't awfully hard. Just practice first. There are plenty of tips in Railwire on soldering track successfully.

I only used unitrack in my helix the rest is atlas flex/switches and some hand laid track/Switches

As for removal in case you Eff up at any point it can be fixed rather quickly

[eric220]

I'm still caught between cosmetics and reliability. It sounds like sectional will be a lot of work to make it reliable, and any fixes will mean soldering in cramped, awkward places. I'm OK with doing the work to get it right, but I really don't want to go through all that work and then have problems.

For all the concerns about superelevated Unitrack causing stringlining that I've read, I can't recall anyone having experienced it. Every experience that I've read about says that it works just fine.

The more I think about this the more I'm coming to the following assessment of the situation:

Unitrack:

• Serious cosmetic issues that would need to be addressed.
• The theoretical maximum limit of what can be pulled up it is lower due to superelevation.
• It is designed so that the actual reliability will approach the theoretical upper limit.
• The connection between pieces are solid, but flexible, meaning any force that would want to change the track geometry (bumping the layout, expansion, etc.) could be absorbed.

Sectional:

• Cosmetically matches the rest of the layout, so cosmetic finishing is identical.
• The theoretical maximum limit of what can be pulled up it is higher.
• It will require a lot of work to approach the theoretical upper limit, and a minor mistake anywhere in assembly will cause the actual reliability to plummet.
• The connections between the pieces are rigid, meaning any force that would want to change the track geometry will either be rejected or cause a failure, causing the actual reliability to plummet.

Given that the helix is right next to the door to the room, there is a strong possibility that it will get bumped and nudged on a regular basis.  I'm envisioning a lot of maintenance down the road with sectional track...

[DKS]

IF you pre-assemble the helix in large-ish sections (say, half-turns), testing each section as you go, then testing assemblies as you build the helix, once all is said and done I would not foresee much in the way of maintenance issues. Most of my portable layouts have been sectional track, and they get more than just the occasional bump. Yes, it will require much more work to achieve, but I think the end result will be worth it. IMHO, FWIW, YMMV, etc.

[GaryHinshaw]

I think you are approaching the point of analysis paralysis here Eric.  I really doubt there is much difference between Unitrack and Atlas sectional track reliability-wise, if properly installed.   As DKS says, just test thoroughly as you go.  Assuming you are planning to glue or nail the track in place, it will hold up just fine.

Regarding string-lining, I do have some experience with that. I have 0.02" super-elevation on all my mainline curves (18" min rad., 2.2% grades) and none in my hidden track.  There is no discernible difference between the two with respect to string-lining.  The big factors have to do with the cars themselves: their weight, location in the train, and how inset the trucks are from the end of the car.  That said, I don't know how high the Kato super-elevation is.

I think you should go with Atlas sectional, and test as you go.  You'll be able to make it plenty reliable.

[ChrisKLAS]

As another data point, here's the first real "test" of my helix using Atlas c55 sectional track. The helix has been in place for about 9 months now with no issues at all (while I've had to fix at least 20 flex track kinks elsewhere due to benchwork contraction).

[eric220]

Chris, interesting. One of my concerns was the cork roadbed. This might be a good situation to forgo it and just glue the track straight to the ply.

Gary, I don't doubt that this is easy to over analyze. In this case, the decision of which type of track to use will define the shape of the helix. That means this is a decision that I need to make before embarking on the project. With regard to the superelevation, I very much suspected that other factors would be far more important in causing stringlining.

I very much appreciate all the input with the various experiences that people have had. That first-hand experience is what I'm looking for.

[CodyO]

any fixes will mean soldering in cramped, awkward places.

This

Can anyone else remove the helix recut supports and reinstall it by yourself in under 8 hours?

[eric220]

Cody - I don't think anyone is debating how fast Unitrack can be installed. Keep in mind, my helix is supported by threaded rod. I can adjust the grade with a wrench.

[DKS]

At the risk of throwing the proverbial thought grenade into the room, have you considered a nolix in lieu of the helix?