# soldering advice



## dooper (Nov 9, 2015)

I am fairly new at fixing American Flyer engines, but have read a good deal on the subject and had success at cleaning and fixing older engines. I am trying to repair a SIT unit and am having trouble soldering the field wires. Is there a secret to this? Any help will be greatly appreciated.


----------



## DonR (Oct 18, 2012)

For model soldering you'll want a 25 watt or so pencil soldering iron
with a fairly narrow tinned point, resin flux, and solder.

If there is enamel on those wires you'll want to removed it
before soldering. Then apply a small dab of flux to each wire
to be attached. Tin each wire by taking a small dab of solder
to the wire on the tip of the iron, rub the wine in the melted
solder until you see the tin on the wire. 

Then attach them, or if splicing them together make a twist
connection/ Then take a dab of solder to your joint and touch
the tinned wires with it. The solder should immediately migrate thru
the connection and harden. Done, unless you need to apply
tape for insulation.

If there is a tab to connect to, I've found that sometimes the
metal used doesn't take soldering as easy as some other
metals. You may need to apply extra solder.

Don


----------



## flyernut (Oct 31, 2010)

On the field wires, you MUST scrape the enamel off of the wire. I use either sandpaper, or the edge of a razor blade. You'll see the wire turn color as you get the enamel off. It should turn to a nice shiny copper color.


----------



## sjm9911 (Dec 20, 2012)

What they said is spot on. The tinning is key. And clean tips. I can't solder well I found a butane solder iron. Heats up fast and melts the solder quickly. That helped me, otherwise I got cold solder joints or melted parts. Soldering is not my thing.


----------



## dooper (Nov 9, 2015)

thank you all. I will give it a try.


----------



## flyernut (Oct 31, 2010)

Tinning and clean tips are the key.. After soldering I rub the tip on a wet sponge. That doesn't work all the time so I use my dremel with a abrasive disc to file it down to clean metal.. Sure, I use a few tips but I like the results.. It beats cursing, swearing, and kicking the dog, and besides, the dog likes not being kicked,lol.


----------



## T-Man (May 16, 2008)

I place the enamel wire end on a metal surface and use a Xacto chisel point to scrape it towards the end. You have to be sure to rotate the wire to get all the sides. Just don't break the wire to goes to the center of the coil.  If you do you will have to unwind it all just to get that inch back and then rewind it.


----------



## gunrunnerjohn (Nov 10, 2010)

I probably do a lot more soldering than most, but I vastly prefer a temperature controlled soldering station for most work. For one thing, you have plenty of heat on tap for heavier work, but with the temperature control, you can do delicate jobs without fear of overheating the material.


----------

