Anybody have any ideas for firm connections other than solder for wiring in the small confines of, say, an HO slope-back tender? In the case of the tender, I need to make wiring connections for the locomotive motor (the motor's pickup through one side of the tender trucks) and constant lighting components (the lighting circuit module and the locomotive and tender lights) which use small wire (~26 or 28 gauge).
True, soldering allows for good mechanical and electrical connection, but solder joints require some sort of insulation to prevent short circuits which could easily occur in the small space inside the tender. Of course, electrical tape works for that purpose, but over time the sticky substance on the tape can loosen and expose the bare joint. Wire nuts (as used in electrical junction box wiring) is another method, but I haven't seen ones small enough to hold 26 or 28 gauge wires firmly.
Heat shrink tubing is your friend. I have some that shrinks over 30 gauge wire just fine and stays pretty flexible. It is truly a "miracle product" for anyone making small wire connections.
IMG_8212 by Edmund, on Flickr
This pin connector, for instance, has five short lengths of heat shrink tubing. This would be a messy job to attempt with ordinary vinyl tape. There is also a brush-on insulating liquid but I have never had the opportunity to use this.
On the right side of the connector in the photo shows the amber-colored kapton tape. It is much thinner, more durable and the adhesive is more stable than plain vinyl electrical tape. This tape is also a helpful material to have in your model wiring toolkit.
For example —
https://tinyurl.com/y78aonur
https://tinyurl.com/y9zahagh
Good Luck, Ed
Heat shrink tubing is great stuff! Just remember to put the heat shrink tubing on one wire before you make the connection.
Kapton tape is also great stuff! Its adhesive won't give up over time. It was designed for use in spacecraft. Just try to avoid touching the adhesive.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Use connectors for the interconnection between loco and tender. Also use smaller wire - DCC decoder wire is about #30 and very flexible. Within the tender itself - nothing is going to take less room than soldering the connections and using heat shrink for insulation. Just use the proper tool. A soldering station with a fine tip is the best, inexepensive and with a different tip can be used for all sorts of soldering jobs, but lacking such, a small 15-25 watt iron with a fine tip would work for the small wires.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Wish I had some pics, but a friend of mine scratch builds locos in N scale. He has some with slop back tenders that contain the motor AND a DCC decoder. And he solders all the wires. Frankly, not even something I would want to attempt. And before anyone says "he must be a young guy" nope, he's older than I am. And he doesn't have a fancy soldering iron or anything. Nor is he an electrical/electronic guy - he's a lawyer. An HO scale one - that's HUGE in comparison.
Hey, thanks to all for ideas...I'd heard of heat shrink tubing, but didn't know it was available in very small diameters. The Goop and tape sound good, too.
Re the N-scale slope-back....your friend must have a very steady hand!
Those SIP and DIP connectors are great. I used them on my DC locos for operating MU connectors (MR, Sept. '92). They pass track and constant lighting power between locos, and to passenger cars.
Genesee Terminal, freelanced HO in Upstate NY ...hosting Loon Bay Transit Authority and CSX Intermodal. Interchange with CSX (CR)(NYC).
CP/D&H, N scale, somewhere on the Canadian Shield
Canalligators Those SIP and DIP connectors are great. I used them on my DC locos for operating MU connectors (MR, Sept. '92). They pass track and constant lighting power between locos, and to passenger cars.
The female will double as a male by reversing it but the male connector has a tigher fit.
I use mini-connectors similar to those which Mel shows...
...and solder them to the wires, then cover the joints with heat shrink tubing...
I also use the round ones, which go together easier, but they also come apart easier, too - sometimes too easily. For those, I usually tin the male connector, which increases its diameter just enough to prevent unwanted disconnects...
I'm using them simply for all-wheel current pick-up on the tenders, as I'm running DC only.
Wayne