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Discussion Starter · #1 ·
What I would like to know is it benificial to put copper tape over the joints on the scalextric track to improve continuity off the rails. I have only recently created a permenant track and I am using ssd, would it help the digital system from spiking and the like that it is meant to be prone from?

I welcome any advice on this matter.

Thanks

Terance
 

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Prof I T
Ting Tong
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hi
yes it is very beneficial as long as you go for the type with conductive adhesive.

Most ssd digital users tend to go for inox MX3 these days though. It is a liqiud that is applied to the rails to help conductivity wich it does superbly.

There are several threads on the stuff and thankfully it is now easily available here in the uk at long last.
 

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If permanent I would consider wire taps AND maybe soldering each track section together with short leads instead of copper "sticky mess" tape
 

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Just a reminder that copper tape, when applied over the full length of the track reduces the overall resistance of your track. It also increases laptimes by
"ramping" over each track joint. Soldering does nothing beyond reducing "losses" at each joint, although the wire taps effectively reduce resistance local
to the tap. I've done both approaches (and to both Scalex and Carrera) and compared them...there is no doubt at all which works better. Especially with
Scalex which has larger issues with "bumps" from poor fits at each track interface. I invite advocates of hardwiring to add copper tape to their already-
hardwired track and measure the improvement in lap times. So yeah, my advice is to go with the copper tape (be sure to get the tape with the black
conductive adhesive backing).

John
 

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Greg Gaub
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John, are/were your track(s) in temperature stable environments, or were they open to wide fluctuations in temperature as an uninsulated garage, attic, or shed? I've read of some people who find that over time, the tape can break at joins. While this can certainly be patched, it's at least worth mentioning.
 

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hi, Greg

I'm glad you bring that up. It's an "old chestnut" I'd really like to address. First of all, to answer your question directly, my tracks were tested outside in a garage
which ranges 30-50 deg F over 24 hours. Later, I tested indoors in a room (the track is immediately beneath a large South-facing window) that receives intense
radiation throughout the Summer (creating surfaces well over 120 deg F). I live in the mountains...in a desert....so both intense radation, and huge temp swings.
It might be fun to point out that this is where much of the world's automobile prototype testing is done, for just that reason.

As I've mentioned before, by simply slicing any areas that want to pull away under extreme temperature, and bridging with a 2 inch patch, as you say...you
effectively create an expansion joint which allows for future expansion and contraction without either tearing or pulling up. I've never had a single such
joint need to be replaced or altered, even 6 years later. Although I do burnish the whole track every 6-8 months.

My reason for suggesting that someone with a hardwired track quantify results before and after copper was not meant as a challenge btw, but rather as the surest way
to really demonstrate the difference. When i did my own testing, I didn't foresee all this interest or I would have captured the information with numbers and pics.

Btw, as a retired Failure Analyst (mechanical engineer), I can tell you that you can't actually rip the copper tape from expansion/contraction. For several reasons, two
of which are the following...the first is that nothing ever breaks from temp expansion alone, thermal stress is generated by the object putting stress on itself...once it
begins to yield, it has nothing to push against (yield stress is lower than ultimate stress). The second reason is that it's a membrane and can't sustain bending stresses,
only tensile stresses. So again, it will simply stretch and get skinnier, not tear (which requires shear or bending).

My main concern is to give a full set of options to a new poster (lips172), however I am quite willing to discuss this further with anyone interested. And...I've love
to see someone run the test (!)

John
 

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you could also use electrical repair paint. the type you use on rear windows when the heater strips get scratched. mix with a bit of pure acetone and blob a little on each joint. it wicks in, cos you,ve thinned it, and it works. only for permanent track. john
 

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Prof I T
Ting Tong
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hi
i did ask about using electrical repair paint and was told that it is highly corrosive.
 

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i dont honestly know about it being corrosive, but if it joins a break in copper tape, i cant imagine it would be. perhaps some one who knows the answer could chip in. its the quickest way by far, but not the cheapest. its to late for me as i,ve allready done it. john
 

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Well, I'm a little afraid at reading this...

I'm currently building a permanent wood track in a room that is not insulated at all. Since I live in Montreal, Quebec, temperature in this room can go from -15°C in winter to +40°C in summer (about 5 to 105°F).

I will be using copper tape with conductive backing. The track will be made of four 2' x 4' MDF panels. Do you think I will have problems with the copper tape pulling up and/or breaking, or maybe the wood will expand and retract in the same proportions?

Thanks,
Christian
 

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No worries everyone has reasons for the way they do things, here we see them all and use what we want!


I much prefer copper short term, for all reasons stated above. BUT I hate replacing the worn and broken sticky sticky stuff
as I stated
 

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Discussion Starter · #12 ·
Thanks for the responce everyone, most helpfull, I think tape is my only option as the track is already down and secured in place, so wire taps are not realy possible, but still mulling over the whole idea, may look into the inox stuff aswell keep all options open.

again thanks for the assistance

Terance
 

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Prof I T
Ting Tong
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hi
as long as all the rails were crimped before you laid the track inox is a great product to have and use.
 

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Slot King
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I have used all 3 methods to maintain our club track.
I would always recommend copper tape. It's cheap, easy to lay, and easy to repair.
Conductive paint has no mechanical strength and starts to crumble as soon as it's dry. Conductive glue might be a better option (has anybody tried that??).
Soldering wires across all the joints is a nightmare job to do, and it's very difficult to repair the inevitable dry point once the track is down.

But I would cover the whole track, not just the faulty joints.

Joel
 

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hi, Christian (Fastwagon)
I agree you have extreme conditions, but I think it's just a matter of a little planning. First of the MDF won't "move" much at all...it's going to be the copper riding on a
film of conductive glue that does all the moving. I'd suggest that you actually lay the tape under intermediate conditions...say around 60 deg F for your situation. The big
thing is not to stretch the copper as you lay, and be especially careful around turns..it's very easy to stretch while trying to conform to turn.

That being said...just burnish really well when you get done...and watch what happens. Any areas that pull up or bubble over time, just slice through them and put a
generous patch over them (at least 1 inch before and after the slit).

I'm sure things will go really well!! Best of luck

John

PS by burnishing, I mean to use the cap of a thick felt pen (like a "Sharpie") and rub the copper really well along its length. This will flatten all the wrinkles and bubbles nicely and partially liquify the conductive paste to give you good adhesion and good electrical connection at any patches. It doesn't hurt to repeat that process every once in a while. By the way...absolute worst case for you will be that you simply re-burnish in the cold of Winter and heat of Summer. No worries !
 

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QUOTE (John Cahill @ 21 Jun 2012, 10:06) <{POST_SNAPBACK}>The big thing is not to stretch the copper as you lay, and be especially careful around turns..it's very easy to stretch while trying to conform to turn.
The "don't stretch" advice only applies to copper tape which is prone to fracture if stretched.

The copper tape made for slot car track must be stretched as it is put down. particularly in turns. In my experience of quite a few tracks with this sort of tape, it always stays down better when stretched and it never gives any problems due to stretching.
 

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Hi Guys,

I have a stupid question
Does sticking copper strips on the rails affect the downforce if you run magnetised cars?

Thanks
Bryan
 

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re:The "don't stretch" advice only applies to copper tape which is prone to fracture if stretched.

I don't want to get into "cold working" of copper or stretches which are below yield stress and store the energy...let me just
say that both in theory and in practice, and in extremes of temperature mind you...I believe that stretching is neither
necessary nor advantageous, most especially on turns. Whenever I have had bubbling or lifting, it has been on turns...and
always relieved by slicing the tape and allowing it to "relax". The fact that a gap opens up after splitting is a pretty good
indication of "below yield stretching/deformation"...the fact that bridging with an expansion joint after splitting prevents any
subsequent pulling up confirms that IMO.

John
 
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