60/40 vs. 63/37 Solder
in [Repair]
|
Prev: Telephone wiring 101.
Next: Valve/tube, A/R fault
From: Jim Yanik on 15 Jul 2010 17:35 "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote in news:i1nqh7$7qt$1(a)news.eternal-september.org: >> Because it is a eutectic mixture, 63/37 does not have "much >> of a plastic state". This means it is more [sic] sensitive to >> movement in the joint while the solder is cooling -- if the >> connections are unstable it forms more [sic] dry joints. > > I don't what you meant to say, but what you did say is backwards. > Eutectic solder is less likely to produce a dry or crystallized joint. > > > I agree; the eutectic joint solidifies faster and thus less likely to move while the solder is still "plastic". -- Jim Yanik jyanik at localnet dot com
From: Smitty Two on 16 Jul 2010 00:14 In article <i1nhau$vj6$1(a)news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote: > >> The only reason 60/40 was ever manufactured in the first place is > >> that tin is more expensive than lead, so 63/37 solder costs more. > > > Cite, please? (and I don't mean a link to commodity prices) > > I can only cite "common sense". 63/37 has always been more-expensive than > 60/40. Then you can't substantiate your contention that 60/40 was THE worldwide standard for tens of years just because it was a few pennies cheaper per pound? That is the statement of yours with which I take issue.
From: William Sommerwerck on 16 Jul 2010 02:53 >>>> The only reason 60/40 was ever manufactured in the first place is >>>> that tin is more expensive than lead, so 63/37 solder costs more. >>> Cite, please? (and I don't mean a link to commodity prices) >> I can only cite "common sense". 63/37 has always been >> more-expensive than 60/40. > Then you can't substantiate your contention that 60/40 was THE > worldwide standard for tens of years just because it was a few pennies > cheaper per pound? That is the statement of yours with which I take issue. I have no objection to your objection. However, 60/40 was never, ever, "a few pennies per pound" cheaper than 63/37. For the last 30 years, the price of eutectic solder has been sufficiently higher to make one think twice before buying it. The last time I purchased solder, I decided that a one-pound roll of Kester 44 would last the rest of my life, and I splurged. (At this point in my life, my prediction is coming true. I rarely solder any more. If I drop dead, someone digging through the junk will find a pleasant surprise. Assuming they know what 63/37 is.) I just checked Parts Express, and a 1# roll of Kester 44 60/40 is $22.23. 63/37 is $26.85. That's a $4.62 difference, almost 21% more -- hardly "pennies per pound". When I bought the same product some years back, my memory is that the price was around $7.50 for the 60/40, $9 for the 63/37. Even that wasn't "pennies per pound". I looked at the MCM site for Ersin products. Get this... MCM describes its house brand of 60/40 solder as "provid[ing] the lowest possible melting point". Businesses almost always try to cut every corner they can. If you think your solderers -- or soldering machines -- are doing a good job, you might prefer to buy the less-expensive 60/40. When I worked at Bendix Field Engineering, I often walked through the section where a bunch of women (never men) soldered assemblies, following NASA standards. I never thought to ask whether they used 60/40 or 63/37.
From: William Sommerwerck on 16 Jul 2010 04:17 > Rosin flux can be removed with 99% isopropyl alcohol > ($1 a bottle at your corner drug store). You won't find 99% for $1. (91%, maybe.)
From: GregS on 16 Jul 2010 09:40
In article <i1p4j1$t6b$1(a)news.eternal-september.org>, "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote: >> Rosin flux can be removed with 99% isopropyl alcohol >> ($1 a bottle at your corner drug store). > >You won't find 99% for $1. (91%, maybe.) If you can get 95% ethanol, I thinks its best. By the time you use 98 or 99% it absorbs water anyway on the board, and you still have a water residue. You can also drink it. greg |