Track installation and soldering Q's : LUSENET : Wiring for DCC : One Thread

I'm getting ready to build a layout using Atlas code 83 flex and #4 turnouts. I've been studying up on laying track at this wonderful site. I'd like some feedback on my thoughts.

The layout is a 11'x7' shelf unit 2' wide. I plan on using Atlas terminal rail joiners dropped down to a 12ga wire buss. I'm looking at two feeds per power block, two power districts and about 4 power blocks per district.

Now, how do I solder the rail joints with rail joiners?? (without melting everything!) I guess with the Flex, I remove some of the ties and replace after soldering. What about at the turnouts?

I'd also like suggestions on the following:

What size and type of soldering iron?

What type of solder and Flux?

How to connect the block power drops to the wireing buss?

-- Jeff Frederick (, January 25, 2001


Some practical experience from an old head :-)

If you're going to stay in the MR hobby, learn to solder or consider taking up stamp collecting. With that said:

Forget the Atlas terminals- Drill a small hole near the outside of a rail- Using solid wire of #22 to #26 guage (scrap telephone cable is excellant) fold a short ell and dress it against the rail and solder. Don't do this near a rail joiner. Underneath, press a short brad in to the wood support and use it as a tie point to solder this small track wire to your #16 feeder. #12 is overkill, hard to handle and a waste for the railroad size you have.

Solder your rail joiners, and do it before you bend the curves. You'll have plenty of expansion room in the isulated joints. The rail don't expand, your benchwork does as a function of seasonal moisture. At the joints, trim the "spike heads" from the plastic ties and have the ties in place when you solder. While the joint is still warm, lay a block of wood on it to make the warm joint settle into the plastic tie(s). Practice on some scrap and soon you'll make perfect joints with no tie damage. If you ruin a couple, slip some some more in and reheat the joint to settle it in.

Iron: A Radio Shack, cheapie iron, 25 watt will do the rail nicely but would be a slow doer for the bigger wire. You can help it a lot by tightly wrapping a few turns of #12 solid wire around the base of the tip to increase its mass and hence heat storage.

Solder: Use ONLY electronic grade solder, 60-63% tin- Anything from the hardware store is likely no good. Go the the Shack. Small diameter is more universal and nicer to work tiny joints with, but costs a little more.

Flux: After cleanliness, flux is next most important. Dip the wire in it or apply to the joint BEFORE you solder. Yes, the solder is supposed to have flux in it, but it comes TOO LATE if you get any at all on a tiny joint. Use the paste stuff from RS, or get a bigger snuff size can from the plumbing store.

Acid Flux: Listen to the screams. "do not use acid core solder" for any electric work. True! But-- Get a bottle of clear liguid solder flux from the welding shop. It's acid! Put some in a tiny container (I use a plastic film can with an insulin syringe sans needle stuck thru a hole in the top) and use only a single drop on your joint. The solder will flow like magic long before the plastic ties are at risk. Now just wash it away with a water spray or tooth brush dipped in water and the joint won't turn green. Sponge up the water/acid with a paper towel or leave it for the ballast to absorb. You must use this kind of flux for steel and galvanized metals.

See our Teton Short Line web site at: for ideas

-- Wayne Roderick (, January 25, 2001.

Yes you will have to remove the end ties from flex track and many brands of switches. A quick press with a utility knife from the bottom side will do the trick. Save the cut off ties to slip under the joints later for an improved look.

Atlas code 100 and 83 nickel silver rail solders quite easily. Use a temperature controlled soldering iron, 30-50 watts. See Weller WP35 & Easy Braid DJY-40 in the Digikey catalog. Use a 3/16 (5mm) wide chisel tip, Weller ST4. Learn to use a wet sponge to wipe the tip clean.

Riser wires should be 22 awg pre-tinned for HO scale rail. Use Kester "44" or other RA type core solder. #21 awg 0.031 dia works well. Larger sizes are more difficult to work with.

Bring up riser wire from underneath. Bend in a J shape to lay against the outside of the rail at the botton flange for about 1/8 inch. Pre-heat the iron till you hear the thermostat click in & out. Wipe the tip. Place flat end of iron to touch wire & rail. 2 seconds later touch solder to wire, rail, & tip simultaneously. Remove solder when you see it flow out from under the wire (~2 seconds). Remove iron when solder flow stabalizes (~2 seconds). Let it cool without movement.

Solder rail joiners in much the same way. Again, only on the outer side of the rail. Touch both rail ends and joiner with the hot tip. Add solder till it starts to flow out from under the joiner. Remove iron when solder flow stabalizes.

Under the table, use wire nuts, 1/4 inch fast-on terminals, or old fashioned solder terminals (still available from Keystone) to connect track drops to #18-14 awg power feeders. Insulation displacement squeese-ons don't work well with solid wires. #18 copper bell wire is low cost & adequate for a moderate HO layout. #16 or #14 should be used for larger layouts. Some installations use 'romex' home wiring for mains distribution, but stripping it without cutting and re-terminating is a lot of work.


-- Don Vollrath (, January 26, 2001.

See my web page. There is a whole section on soldering.

Allan Gartner

"One of these days" I have a whole bunch to add to the soldering page. Check again in six months maybe?????

-- Allan Gartner (, January 30, 2001.

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