Soder-Wick Unfluxed Desoldering Wick

Out-of-date solder wick can create a performance issue. As more oxidation builds on the copper braid, it will take longer to activate and draw up solder. It will slow down a little month-to-month until eventually the performance will be unacceptable. We estimate this to be 2-years based on average storage conditions. Wick in storage wrapped up tight can last longer, while a loose bobbin sitting on a benchtop will probably go bad sooner.

An operator will generally have a feel for how wick performs and will have an opinion on when performance is unacceptable. The main risk of using out-of-date wick is thermally stressing the working area, adjacent components, etc. When an operator tries to make due with old wick that is underperforming, they tend to turn up the heat on their iron, or keep the tip in contact with the wick and work for a longer period of time. 

So whether or not out-of-date wick is considered good depends on the criticality and conservativeness of your process. An average shop would keep using it until it stops working well.  A very conservative process (e.g. for class 3 electronics) could require wick in stock to be discarded at the expiration date, and loose bobbins at workstations replaced periodically (i.e. weekly or monthly).

The shelf life of a product can be found on either the technical data sheet (TDS), available on the product page, or by looking on the certificate on conformance (COC). The COC can be downloaded by going to https://www.chemtronics.com/coc. Once you have the shelf life, you will need to add it to the manufacture date for a use-by date. The manufacture date can be identified by the batch number. The batch code used on most of our products are manufacture dates in the Julian Date format. The format is YYDDD, where YY = year, DDD = day. For example, 19200 translates to the 200th day of 2019, or July 19, 2019. This webpage explains and provides charts to help interpret our batch numbers: https://www.chemtronics.com/batch-codes.

Desoldering braid (wick) is made of fine strands of ultra-pure copper woven and coated with flux. Its geometrically precise weave design allows for maximum capillary action and solder capacity. Soder-wick optimizes heat transfer through the braid and into the solder joint, resulting in faster wicking action than any other competitive brand. Minimal flux residue on the board speeds up the cleaning process or eliminates it entirely.

1. Place the braid over unwanted solder, preferably on the greatest solder build up so that it maximizes the contact of the braid to the surface area of the solder.
2. Next, place your iron tip over the wick at 45 degrees and allow heat to transfer to the pad. Molten solder will absorb into the braid.
3. Move the solder tip and braid as needed to remove all of the solder at one time. Careful not to drag the braid over the pads, which can scratch.
4. Once the braid is full of solder, you must trim the spent portion and move to fresh braid in order to pull more solder. Remove the iron and braid simultaneously to avoid soldering the wire to the board.

Yes. As the copper is exposed to the open air, oxygen and moisture in the air interacts and oxidizes the copper. This oxidation is most apparent by the color of the wick. The brighter the copper, the fresher the wick. Oxidized copper will darken like a dirty penny. The more oxidized the copper, the slower the wicking action. We generally recommend replacing wick after 2-years, but that can be longer or shorter depending on storage conditions. Keep the wick bag or can sealed for maximum product life. If you have wick that appears to be too oxidized to use, unroll around 6”, trim off, then test the remaining wick. The outside of the spool of wick becomes oxidized first.

The temptation is to desolder an area and keep moving up the spool of braid. However, it’s best to work towards the end of the braid to isolate the heat. Once the desoldering braid is brought up to soldering temperature, the flux has been fully activated, so that part will not draw more solder. A long strand of used braid only acts as a heat sink, slowing down your process.

Desoldering braid or “wick” is a pre-fluxed copper braid that is used to remove solder, which allows components to be replaced and excess solder (e.g. bridging) to be removed. The soldering iron is applied to the wick as it sits on the solder joint, and when both are brought up to the solder's melting point, the flux is activated and, through capillary action from the braided design, solder is drawn up the wick.