Steel Track or Nickel Sliver ?

[r.cprmier]

Jim;
If you are bonding copper to aluminum, do use either "Penetrox" or  "Alenox", or a comparable anti oxidant.  This will prevent any deterioration by electrolysis; also by the elements.  Actually, when using two dsissimilar metals where that type of business can happen, you should keep the two metals segregated.  In the case of electrical work such as a service or any splice with CU/AL conductors, a split bug is used.  With the type of thing here, I suggest using stranded copper, stakon(@) type connectors, screwing it to the rail in the way you mentioned, and penetrox the whole affair.  If you are not using the rails for power, or communation,
a good idea would be to ground it with a driven ground rod (5/8" CU plated steel rod) available at supply houses.

The Old Reprobate

[Jim Banner]

Hunt, I suspect the failing aluminum tracks might have been ones where the stiffness of the track was provided by the rails instead of by the substructure. 

Grumpy, I just checked Caboose Hobbies and they have Micro Engineering aluminum rail in stock, both code 250 and 332.  But they are out of flexible tie strips.  Personally, I do not use the latter, preferring to spike my rails to cedar ties glued to a base board.  I use Micro Engineering large (1/2") spikes and like the way they rust a bit, increasing their grip in the ties.   I find their price on ties to be quite high compared to cutting my own out of cedar fence boards.  I rarely use rail joiners - in my opinion, even the best of them do little more than help align the rails.  In the places where I do use joiners, I bend them up as needed out of scrap .020 brass.  Caboose also has some code 250 nickel-silver rail in stock.  At triple the price of aluminum, I don't use much of it.  But I do like it for the frogs and point rails of turnouts.  The extra strength makes up for the reduced cross-section in the tapered ends of the points, and being able to solder it makes a much stronger frog.

Rich, I am aware of galvanic corrosion but have not had the problem.  I originally considered welding on aluminum bonding wires but ended up using solid copper instead because it is a method that anyone can use.  So far it has been very satisfactory, although I would not want to guarantee it for 50 or 100 years or whatever the design life for electrical wiring is these days.  A friend uses stranded copper and plated steel screws with his code 332 aluminum rail and each spring has to replace several of the bonding wires.  The ones that fail always show completely blacked copper strands.  My own solid wire shows bright copper in the gas tight areas.  My conclusion is that his stranded bonding is NOT gas tight.  Crimp on connectors would probably give him a gas tight connection to his stranded wire but even with his larger rail they would be a problem to attach.  I will pass on the advice to use an anti-oxidant though.  And will try some myself.  I do use my rails for both power and communication - I use DCC for most of my trains.  I am not sure if the rails are held at ground potential by the booster when the power is off but will check.  If not, it would be easy enough to connect each rail to a ground rod through a small 9 volt lamp.  This would provide a low resistance path when the DCC power is off and a much higher resistance path when the DCC power is on and the lamps are lit.

[r.cprmier]

Jim;
If you are using your rails for either power or com, I repeat, use a bond to ground only if neither issues exist.  The bond to ground is primarily for voltage surges and lighting protection.  In terms of stranded copper, I have found that condition numerous times on outdoor connections in wet/damp locations.  Where the rail is so close to the ground in most applications, it would, I believe, be a prevalent condition.  However, the blackening can be caused by not only oxidation but also by electrolytic action (galvanic) as the copper, being the harder of the two, will tend to conduct the aluminum to it, and can cause a bit of plating, which can cause that black colour.  Again, I say use the anti-oxident on the whole; and, with periodic re-application, should largely prevent that from happening and permit trouble free operation.  Also, my experience with this stuff is that it really doesn't take much of a resistance to raise holy merry hell with conductivity, where something like communications might be employed, or even  at 18 volts pressure.

The Old Reprobate

[Santa Fe buff]

GG,
What company? Or was it unmarked?
~Santa Fe buff

[Guilford Guy]

I'm pretty sure I stated in my post which company...

[TrampTrader]

I think GG said the company was aristo, wasn't it ?


Pete

[jbrock27]

Who ever is reading this, go with the nickel silver track!