60/40 for desoldering or a different type?

[daRk_Kon]

what do you recommend for desoldering? 60/40 or a different one?

btw, i think im going to go with the hakko 936, hopefully its a good soldering station

[linuxguru]

Re: 60/40 for desoldering or a different type?

I use 63:37 for desoldering, 60:40 for soldering. YMMV, but I find that 63:37 corrodes metal tips, especially desoldering tips, faster than 60:40.

[999999999]

Re: 60/40 for desoldering or a different type?

Desoldering requires no solder. Get some flux to reflow what solder is there. REsolder with 63/37 ideally though 60/40 can work fine so long as you keep the part completely still while the solder sets. If you happened to have both types of solder and no flux and insist on using only solder to get more flux on a joint, the 60/40 may be easier since it remains plastic longer (but for this reason it is also less optimal for the soldering in of the replacement part). A bottle of liquid flux is very handy if you do much soldering.

The difference in 63/37 and 60/40 corroding tips is not due to the % of metal in either, it's due to the type of flux used. Generally there are (several types and even more today with lead-free solders but within the tin/lead alloys the general classifications are):

- Acid Core - Not meant for electronics work, use it on stained glass or plumbing. In an emergency you could use it on electronics if you really must, but all the flux must be completely cleaned off or it will corrode the metal and the the metal in the flux solution can be conductive.

- Rosin Core - General electronics use, better for oxidized parts. Eats soldering iron tips far slower than Acid Core but faster than Mildly Activated types.

- Mildly Activated Rosin Core - Milder flux, gentler on parts and irons, is an ideal choice if your parts aren't heavily oxidized (and they shouldn't be, a factory tinned cap lead can be wiped with a paper towel if it's really bad and a board has been plated already

- No-Clean Core - Synthentic substitute for Rosin, non-hygroscopic so it doesn't need to be cleaned off and hardens to a tough clear-ish coating. Not easily removed without flux-specific solvent (won't usually clean off with alcohol like rosin core will). Usually slightly more active than Mildly Activated Rosin, but not as much as regular Rosin.

In general a lead-free solder will have a more active flux even if classified as above, and the higher melting temp in conjunction with that will wear out iron tips faster.