I have a decoder with wires connected to an 8-pin male connector on which a pin broke.
I have some replacement 8-pin male connectors, so I attempted to solder the wires to a new 8-pin connector.
I used a 15 watt soldering pen, and quickly applied heat to melt the solder. But, even working quickly with a low wattage soldering iron, I partially melted the 8-pin connector.
What's the correct method to complete this task without melting the connector?
Rich
Alton Junction
I have made a few custom harnesses with a 8 pin plug. I pretty much melted the first one. Then I came up with a bright idea. Earlier I removed a board from a locomotive ( Kato I think ) and replaced it with a NCE DA-SR. I kept the board for some reason. I found out if I put the board in a rig I bought a while ago with 2 arms with alligator clips at the end of each arm I plug the 8 pin plug into the board then solder the wires onto the plug. The old board acts like a heat sink and I haven't melted a plug since. Hope this helps. I also let the plug sit for a few minutes in the thing a majig after I am done to make sure it cools down so no pins will move around.
Scott O'Dell
If the connector is inserted into a socket then it holds everything in place. Also I find low wattage soldering irons take too long to heat the solder and melt the plastic. A hotter iron melts the solder much more quickly and so the heat is applied for a shorter time.
Which is essentially what Scott suggested,
Simon Modelling CB&Q and Wabash See my slowly evolving layout on my picturetrail site http://www.picturetrail.com/simontrains and our videos at http://www.youtube.com/user/MrCrispybake?feature=mhum
I also plug into a old PC board 8 pin connector and use a fine point 40 watt soldering station set at half temp. Clean iron tip just before soldering. I always tin the decoder wire first.
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
For such small thigns the 15 watt iron shoudl be fine. But the tip ahs to be nice and clean and shiny Otherwise you will have to hold the tip in contact with the pin too long to get enough heat to melt the solder and it will melt the plastic. It should take a fraction of a second, not even 1 second.
You can hold one row of the pins in the alligator clamp of a helping hands sort of device, that will act as a heat sink.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks for the suggestions, everyone.
The heat sink idea is a good one, and I will try it.
Also, on my next try, I will connect the male pins to the female pins on an old board to keep the pins stable.
Interesting point, Randy, on using a higher wattage iron as opposed to a lower wattage iron.
That was Simon actually. Until I bought my soldering sttion I used a 15 watt for all decoder and circuit board soldering, and I had a 45 watt iton for solderign feeder wires to track, and a big 150 watt soldering gun for soldering the heavy bus wire. Now I just use the soldering station for everything but the bus wire, still have the big gun for that, a 40 watt iron won't heat #14 wire very well. A small tip is important - especially on small objects like the connectors, so heat is only applied where you want it.
Indeed I like a very fine tip for my decoder soldering (Weller Soldering Tip, 0.015") in my temp controlled soldering station.
All good so far, I too use an old 8 pin socket on a board method. But it's important too to tin each pin and wire first and use solder flux. I use a pencil point iron 25 watt I purchased at Radio Shack. Jim