Soldering Question--Help Please

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Is there a way to prevent solder from wicking back when soldering stranded wire? Would normally be a non-issue except when needing to keep the cable as flexible as possible. I notice it when soldering XT60 terminals to stranded wire.
 
Yep, use flux, and hold the wire in the direction you want the solder to run.
 
There are several techniques to limiting wicking. You can limit your soldering iron temperature, as well as the dwell time. Another very effective is to use a anti-wicking tool. Just Google the phrase and click images. A simple alligator clip will do in a pinch. The less flux used will limit wicking as well. I hope this helps. If you have more questions about soldering, I'll keep an eye on this thread and try to help.
 
Thanks for the tips! I do use flux and tin the wire and terminal. I have assumed that the solder moves within the wire by capillary action so didn't bother to hold the wire in a vertical attitude. Will give that a try.
The anti-wicking tool is also a new one for me and I assume it works by minimizing the space between the strands. Might be able to improvise by clamping a split bushing on the wire with a tiny pair of vise grips? Do you know what material the tool is made from to prevent sticking to the solder?
 
The anti-wicking tools are normally aluminum (simple clamp type) or stainless steel (tweezer type). You can also use a paper clip. The object is not to squeeze the wire, pinching the strands, but rather create a heat sink. This will preclude the heat from moving further beyond the insulation, which will eliminate the capillary action that stiffens the wire. Tinning can be done in a number of ways, in any position (vertical, horizontal, etc.). I never use auxiliary liquid flux when tinning a wire. That is probably why you're seeing excessive wicking. If you are using a flux-cored solder you have all the flux you need of the tinning process. Here is one method: First wipe the tip to remove all solder, leaving the tip in a clean, wetttable condition. Place the solder in contact with the wire approximately one diameter distance from the end of the insulation. Place the soldering iron onto the solder, melting through to the wire. The flux that is in the solder (normally 3%) will be all the flux necessary to remove oxidation in the process and help the solder to flow. In one continuous motion slowly move the iron towards the end of the wire while feeding a sufficient amount of solder to maintain a ball of solder on the tip, which creates enough surface tension to leave the wire coated with smooth wetted result. At the same time, depending on the solderabiltiy of the wire, the solder will penetrate into the inner strands of the wire. The result will allow the wire to be formed on to the terminal without strand separation and deformation. The tinning process will also make the wire more solderable.
Pardon the excessive verbiage. It's just how I would want someone to explain it to me. Let me know if you have more questions about the soldering process of wires or circuit boards.
 
And for those just starting out and learning how to solder.
Be sure you are using rosin core usually 60/40 for electronics.
Never use acid core solder or flux for acid core with electronics, this is plumbing stuff.
 
Amen to that. The acid, or organic flux will quickly lead to corrosion. 60/40, 63/37 is great. However, these days it is becoming difficult to find it in many stores due to the trend towards lead-free solder. Lead-free is about 40 degrees C higher than the tin/lead alloy mentioned above. If at all possible, try to find 60/40 or 63/37 rosin core. If not, Sn96.5/Ag3/Cu.5 will be the closest you can come to the tin/lead but you'll be wise to raise the iron temp a little or wait a bit longer until you see evidence of wetting. Just keep in mind, the longer the dwell time, the further the heat travels, leading to the wicking you're trying to avoid or thermal damage to the components. The end result will display a solder connection that is slightly duller than what you're used to.
 
eroomomni said:
Amen to that. The acid, or organic flux will quickly lead to corrosion. 60/40, 63/37 is great. However, these days it is becoming difficult to find it in many stores due to the trend towards lead-free solder. Lead-free is about 40 degrees C higher than the tin/lead alloy mentioned above. If at all possible, try to find 60/40 or 63/37 rosin core. If not, Sn96.5/Ag3/Cu.5 will be the closest you can come to the tin/lead but you'll be wise to raise the iron temp a little or wait a bit longer until you see evidence of wetting. Just keep in mind, the longer the dwell time, the further the heat travels, leading to the wicking you're trying to avoid or thermal damage to the components. The end result will display a solder connection that is slightly duller than what you're used to.

+1 I found some 63/37 that's been working great on all my multirotor electronics: http://www.amazon.com/gp/product/B005T8 ... UTF8&psc=1
 

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