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I apologize if this is a duplicate tip.

Lionel has acknowledged continuity issues with the middle rail of some of its FT.  While an irritant, the solution, if caught during installation, was to bend the pin to correct a sizing or misalignment issue. 

If caught after installation, some members have pinched the two middle rails at the joint - tends to raise one or both rails - while others have soldered a jumper wire across the offending joints.

I just had the problem with several pieces of track on my layout and turned to copper foil tape readily available at stores dealing in leaded glass supplies.  I use 1/4" width tape, 01.25 Mil thickness and cut a small piece - about 1/4 to 1/2' in length - to bridge the rail gap.  For the less energetic, simply lay the tape across the top of the rail though to hide the tape, just position it on the side of the rail - a small portion will end up on the FT roadbed.  To avoid the overhang on the roadbed. simply trim the tape a bit narrower and install on the side of the rail.  Only needed on one side.   To avoid cutting, simply buy 1/8" wide tape.  Cost for 50 feet or so would be in area of $6.

The tape is sold with a removable paper cover backing protecting the conductive adhesive.  There are no doubt other uses for the tape.

I began using the tape in the early 60's to improve continuity on 1/32 slot car tracks and in recent years when routing MDF for homemade slot car tracks for the grandkids.

 

 

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Wow, great tip. I thought I was crazy with my fastrack and loosing connection from time to time. Santa is bringing new track for our layout, so seems I need to get this to update. I'm rather disappointed in Lionel. My switches have had issues too where I've had to fix them due to improper manufacturing. 

Be aware there are two types of copper tape. One foil (probably what you have) has plain adhesive on one side, the second foil (used in electronics for shielding like Bradfish1 shows) uses adhesive embedded with minute copper balls.  Applying the first will probably work if enough copper foil breaks through adhesive to the rails.  The second type insures that there is contact between copper foil and rails.

gunrunnerjohn posted:

It's difficult to find good specifications on the actual products when you look.  They use the vague terms like EMI Shielding Conductive Adhesive to describe the conductivity.  No offense, but what the heck does that mean?  I have looked previously, and it's difficult to find any technical specs on this stuff.

I think it EMI sheilding WITH conductive adhesive. They use copper sheets and wraps in sheilding and sealing  computer power supplies now.

gunrunnerjohn posted:

I know what the title says, but I'd like to see actual specifications for how conductive the adhesive really is.

What I would do in avionics lab is use two blunt ended probes and press lightly on each foil side.  If I got a reading then it was conductive high or no reading then just adhesive.  Not foolproof but was good "first look see"

I think the problem with Fastrack continuity has to do with the way it is taken apart. It is almost impossible to pull it apart straight by hand. If you crack one side and then the other, it spreads the rail slightly because of the angle, and gets looser each time. I use a utility knife to start a crack, and then pry it apart in the center with the knife. A table knife will work, but it is harder to get it started. That's why the recrimping helps.

rrman posted:
gunrunnerjohn posted:

I know what the title says, but I'd like to see actual specifications for how conductive the adhesive really is.

What I would do in avionics lab is use two blunt ended probes and press lightly on each foil side.  If I got a reading then it was conductive high or no reading then just adhesive.  Not foolproof but was good "first look see"

Good idea, but I don't want to buy it before I know it's what I want!

I'm going with the tried-and-true 22 ga wire hot-glued to the underside of the sub-roadbed, which will put it in line-of-sight of the lower tracks, thereby "sucking up the excess signal" or whatever one calls the ground-plane function ... Fastened at one end to a rod in the ground, as folks have said using the house-ground wire is unreliable. (why not just a plug with only the ground prong connected to the wire and plugged into a regular outlet??)  This should be simple.

 

The product linked by MIKEWALTER seems to talk about how many ohms per square inch (0.05 ohms), but I assume they mean on the non-adhesive side.

As someone else referred to, I'd be cautious of the current carrying capability of the tape based on the Max posting regarding his small fire.

Creating a more perfect Faraday Cage relating to EMI occurring at very low radiated signal levels is very different than carrying current to run an O Gauge train.

-Dave

Last edited by Dave45681

The conductive adhesive tends to become less conductive and sticky over time. I have used it to prototype antennas on back glass in vehicles. Every day you would repress the tape to ensure proper conductivity. But this is a fussy application.

On MTH roadbed track at my club, we pressed a small piece of this tape between rail ends with a knife. It works well enough.

 

Kerrigan posted:

I'm going with the tried-and-true 22 ga wire hot-glued to the underside of the sub-roadbed, which will put it in line-of-sight of the lower tracks, thereby "sucking up the excess signal" or whatever one calls the ground-plane function ... Fastened at one end to a rod in the ground, as folks have said using the house-ground wire is unreliable. (why not just a plug with only the ground prong connected to the wire and plugged into a regular outlet??)  This should be simple.

 

I thought TMCC/Legacy ground planes separate from the running rails do not carry any significant amounts of, (if any) electrical current, just radio signals?

---PCJ

Dave45681 posted:

The product linked by MIKEWALTER seems to talk about how many ohms per square inch (0.05 ohms), but I assume they mean on the non-adhesive side.

As someone else referred to, I'd be cautious of the current carrying capability of the tape based on the Max posting regarding his small fire.

Creating a more perfect Faraday Cage relating to EMI occurring at very low radiated signal levels is very different than carrying current to run an O Gauge train.

-Dave

In the Q&A...

 

Question: What is it's resistance for 1 inch of longitudinal length? resistivity = ( electrical resistance * cross-sectional area ) / longitudinal length

Answer: I show 8 ohms with the leads 1" apart.

Question: what is max current can this handle?

Answer: This may not be the most useful answer but I ended up returning mine as the adhesive was not conductive (at least my meter couldn't find it).

Yeah, I saw those Q&As too.  I'm not defending the product at all since I haven't used it, but the people answering in those Q&A sections of Amazon aren't necessarily any more qualified than the people asking the question to begin with IMO (unless I'm mistaken, Amazon relies only on other customers' "votes" for whether the reply is helpful or not - someone who failed basic electricity in shop class could be typing in the answers for all we know).  The short nature of the Q&A section doesn't help.

The other ones regarding not using it for anything high current drew my attention a bit more.  There is even one claiming (see my comment above! ) that the stuff would get too hot if used to fix a TV remote button! (would need to know more about the specific problem and remote design to determine if the application for repairing is even reasonable, much less the pitfalls)

I did read further down the page just now to the actual reviews, which while also not fool proof seem easier to guess the writer's knowledge since it's not a "one line" Q&A.  I noted several reviews state the sticky side is not really conductive and you will need to make a connection by soldering to the end of the tape.

Many of the reviews agreed that this stuff is a mess to keep in the spool when you receive it.  Be careful when opening the package taking some off the spool to use it!.

-Dave

Last edited by Dave45681

We have two applications of foil tape discussed here.  The first is track power which can demand considerable amperage and I doubt 1/8" foil tape is suitable to feed track power unless other paths exist for power distribution.  As a quick fix for a weak Fastrack section without pulling up the track and adding decent power feeds, it should work Ok.

For adding a TMCC ground plane, foil tape is a good way to stick the ground plane conductor to the underside of the track support (plywood or whatever).  Aluminum foil duct tape is OK but the 2" width is not appropriate in many situations.  Copper foil in 1/4" to 1/2" widths is easy to apply and hide.  Considering the time and effort of securing and hiding insulated wire ground plane on elevated track, I'll go with copper tape and get the job finished quickly.

 

 

Kerrigan posted:

Does foil work as well as 22 ga wire placed under the roadbed?

After numerous problems with my DCS signal (which I also assume is due to bad FT connections- I have the new FT), I have decided to completely rewire my layout.  For permanent layouts, it seems like a jumper wire across sections is a lot more time and effort, but probably the most definitive fix.  Yes?

Pine Creek Railroad posted:

MikeWalter,

  Yes the very 1st generation had a Black Mid Rail, easy to identify.  The 2nd generation had the same kind of pins, however they are absolutely correctly positioned and very tight in the rails and both these tracks work perfectly.  

PCRR/Dave

Gave away two new Thomas sets, they both have spots where the engine stops as does one from last year.  Did anyone actually test this track prior to the redesigned production?

Is there a YouTube video link I can send them which shows how to crimp the ends?

BobbyD posted:
Pine Creek Railroad posted:

MikeWalter,

  Yes the very 1st generation had a Black Mid Rail, easy to identify.  The 2nd generation had the same kind of pins, however they are absolutely correctly positioned and very tight in the rails and both these tracks work perfectly.  

PCRR/Dave

Gave away two new Thomas sets, they both have spots where the engine stops as does one from last year.  Did anyone actually test this track prior to the redesigned production?

Is there a YouTube video link I can send them which shows how to crimp the ends?

Hi, I actually watched this video today - https://youtu.be/pfI7968aPhg.  I hope that helps a bit.  My goal for the copper tape was to help snug the pins that touch, I have not used any of it yet, but will try and remember to report back after I give it a go with the tape I found.

Tracker John posted:

We have two applications of foil tape discussed here.  The first is track power which can demand considerable amperage and I doubt 1/8" foil tape is suitable to feed track power unless other paths exist for power distribution.  As a quick fix for a weak Fastrack section without pulling up the track and adding decent power feeds, it should work Ok.

For adding a TMCC ground plane, foil tape is a good way to stick the ground plane conductor to the underside of the track support (plywood or whatever).  Aluminum foil duct tape is OK but the 2" width is not appropriate in many situations.  Copper foil in 1/4" to 1/2" widths is easy to apply and hide.  Considering the time and effort of securing and hiding insulated wire ground plane on elevated track, I'll go with copper tape and get the job finished quickly.

 

 

Once the wire is in place under the plywood subroadbed, the plan is it will be hidden by the overlaying scenery in most places.  On the planned trestle .. still thinking about that part.  Foil would show for sure, maybe the wire can be somewhat hidden.

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