开云体育

Started to lay down some track on my modules and then I had a mental block, In N-scale I
lay feeders about evry length of flex track. In Z scale do i do the same thing?? every piece of
flex track, or is it one per module, every some many feet ???? Any sugesstions frome those
who have do it before.

About every three feet or so is good, Stu. If you are using MTL flex track that's only about a foot long so it would be a LOT of feeders if you did one per piece of flex. For Peco or Marklin flex that is closer to three feet long, it would come out to about one feeder per piece of flex track.

Sounds like you are making good progress.

Randy

cgwcnw <ksonta@...> wrote:
Started to lay down some track on my modules and then I had a mental block, In N-scale I
lay feeders about evry length of flex track. In Z scale do i do the same thing?? every piece of
flex track, or is it one per module, every some many feet ???? Any sugesstions frome those
who have do it before.

We had a discussion on this back in March 2005 on the Z_Scale list. MTL rail has about the same electrical resistance as AWG28 copper wire. If a power bus of AWG18 or larger is run under the table, in most cases a feeder connection every 6 feet is adequate. Every 3 feet is even better, especially when running multiple units.

--- In Z-Bend_Track@..., "Glen Chenier" <chenierfam@...>
wrote:

We had a discussion on this back in March 2005 on the Z_Scale list.

MTL rail has about the same electrical resistance as AWG28 copper wire.
If a power bus of AWG18 or larger is run under the table, in most cases
a feeder connection every 6 feet is adequate. Every 3 feet is even
better, especially when running multiple units.

----- Original Message -----
From: randy smidt
To: Z-Bend_Track@...
Sent: Saturday, July 22, 2006 6:15 PM
Subject: Re: [Z-Bend_Track] Track feeders, how many and how often


About every three feet or so is good, Stu. If you are using MTL flex

track that's only about a foot long so it would be a LOT of feeders if
you did one per piece of flex. For Peco or Marklin flex that is closer
to three feet long, it would come out to about one feeder per piece of
flex track.

Sounds like you are making good progress.

Randy

cgwcnw ksonta@... wrote:
Started to lay down some track on my modules and then I had a mental

block, In N-scale I

lay feeders about evry length of flex track. In Z scale do i do the

same thing?? every piece of

flex track, or is it one per module, every some many feet ???? Any

sugesstions frome those

who have do it before.

[Non-text portions of this message have been removed]





[Non-text portions of this message have been removed]

"Glen Chenier" <chenierfam@...> wrote:

We had a discussion on this back in March 2005 on the Z_Scale

list. MTL rail has about the same electrical resistance as AWG28
copper wire. If a power bus of AWG18 or larger is run under the
table, in most cases a feeder connection every 6 feet is adequate.
Every 3 feet is even better, especially when running multiple units.

Hi,

One caveat. That all of the short pieces are well soldered
together. To have one feeder soldered to one piece of rail connected
by rail joiners to others is not a solution. To rely on rail joiners
as permanent electrical connectors is an invitation to frustration.

Some folks solder the rail together for permanent electrical
continuity. Others connect feeder wires to each piece of rail for
the same. Or you may use a combination of the two. Your choice.
Just make certain that, besides having each rail in alignment with
the next, they must have elextrical continuity. Except where you
want an electrical gap. (there is always some kind of exception)

Bill H.
El Toro, CA

Thanks for the added detail, Bill. It's been awhile since I laid any track and am getting forgetful, your caveat is a reminder of other caveats. Soldering the joiners is also a must for kink avoidance when the join is in flextrack on a curve.

Where one might want a non-soldered metal joiner is every few feet on only straight sections with a small gap between rail ends (a physical gap, not neccesarily an electrical gap) to allow for thermal expansion and contraction of the rail without buckling. Bevel the rail inside corners very slighly at the gaps to prevent flanges from picking the corners, and avoid putting large gaps on curves where the flange bears harder against the outer rail. Also place expansion gaps at turnouts to prevent rail thermal expansion from pushing the turnout rails out of alignment (and makes it much easier to replace a future defective turnout) and solder feeders directly to the turnout itself.

How much gap and how often? See below, better to overdo it than underdo, especially if the module will be transported in a car and left parked in the sun. Obviously the gap must be small enough to not derail, about 1/32" or less (approx 0.79mm), and of course have feeders to either side of this gap so electrical continuity is not needed through the non-soldered joint.

A google search found this which lists the coefficient of expansion for Nickel Silver rail(64% copper, 18% zinc, 18% nickel) at 15 parts per million per degree Celcius. Assume you lay rail at room temperature (20C) and want to leave enough expansion gap to withstand up to 70C (the hot car in the sun) so there is a 50C change in temperature, or 50C x 15ppm/C = 750 ppm, or 0.75mm gap for every meter of track.

Realisitically, if you don't ever plan to leave a layout in a car parked in the sun with the windows closed, the worst that could happen is your A/C craps out and the room temperature might rise to 40C on a hot summer day with all the windows open. So with only a 20C temperature rise the expansion is 300ppm or 0.3mm gap every meter, which is a lot easier to handle on a typical layout.

This link has some good info on track electrical issues


Does the new MTL sectional track need to be soldered or is there an auxiliary electrical connection made in the roadbed?

Now I get to go do my Sunday chore which is crawling into a hot attic to replace a burned out vent fan motor. Phewww! Good thing I don't have an attic layout. Must be 60C up there!

Glen Chenier
Deep in the Hot of Texas