Solder Leaded - 100-gram Spool

This is your basic spool of leaded solder with a 63/37 water soluble resin core. 0.031" gauge and 100 grams. This is a good spool for more advanced users that should last 6-12 months depending on how often you solder.

Mix: 63% Sn / 37% Pb

Solder Leaded - 100-gram Spool Product Help and Resources

Core Skill: Soldering

This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.

1 Soldering

Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
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Looking for answers to technical questions?

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  • Duncan Riach / about 11 years ago / 3

    This leaded solder is marked as RoHS compliant. How can that be?

  • KM4HPK / about 10 years ago / 2

    Should it say "Rosin" instead of "resin"?

  • Unless this solder contains tree sap, it should probably say "Rosin core" rather than "Resin core".

  • Skerpy_D / about 10 years ago / 1

    How do you use that? The spool is massive and you can't just break some off.If anyone knows how to use it please tell me, any feedback would be greatly appreciated.

    • Wire strippers or diagonal cutters work well for cutting off smaller pieces to work with.

  • Member #506865 / about 10 years ago / 1

    I'm a complete novice -- never soldered in my life, but about to start! I've read that water-soluble flux is harsher (more corrosive) than rosin and I've read warnings that say it can damage electronics if it is not removed from all the nooks and crannies after soldering. I figured I would only use solder with a mildly activated rosin flux core but I can't find any solder in the Sparkfun store that fits that description. This item description says it has a "water soluble resin core", so should I be worried?

    Also, the description says it is a good spool "for more advanced users". What is it about this spool that makes it good for advanced users? (Is it just the fact that it is a large quantity? I couldn't find a smaller quantity in the store for leaded solder.)

    • threadzless / about 10 years ago / 1

      As far as the "for advanced users" part, it's probably referring to the solder being 0.031" in diameter, which is small enough to be usable with most SMD components.

  • Member #420755 / about 11 years ago / 1

    why dont you have a smaller diameter?

  • charredgrass / about 11 years ago / 1

    This solder won't be a risk of lead poisoning, right? Unless I do something stupid like eat it.

    • MikeGrusin / about 10 years ago / 1

      Correct. None of the metals will vaporize at soldering temperatures, so you won't ingest any lead that way. The flux does vaporize (which is the little wisp of smoke you see). It's not great for you either, so use a small fan to blow it away from you. The metals will get on your skin while you handle the solder, so be sure to wash your hands after soldering, especially before eating. Follow these steps (including not eating it) and you'll be fine!

  • Member #413600 / about 11 years ago / 1

    So with this you dont need any solder paste or a flux pen?

    • Kamiquasi / about 11 years ago / 1

      For most small work on new boards, from resoldering a tiny SMD resistor to soldering down the small tabs on a barrel jack plug, you should be fine.. the flux core does the trick. For bigger things, say the slotted tabs on a beefy relay or some multistrand thick gauge wire, I still drip some flux on.. just helps the solder spread out (and in) more cleanly.

  • Member #336150 / about 12 years ago / 1

    Sorry, but does anyone know the length of the solder?

    • borisper1 / about 12 years ago / 4

      dSn=7310 kg/m3

      dPb=11340 kg/m3

      dSnPb=7310x63/100 + 11340x37/100 = 8801.1 kg/m3

      S=(gauge/2)x3.14 = 4.86x10-3


      m=dSnPb x S x l

      0.1kg = 8801.1kg/m3 x 4.86x10-7 x l

      l=0,1kg/0.00427 = 23.41m

      so it should be about 23.4 meters long

      • Kamiquasi / about 12 years ago / 1

        You forgot about the "water soluble resin core" ;) Still, A for effort! ( I'm sure it's pretty close :) )

    • you don't really measure solder in length now do you? It's a 100 gram spool. Feel 100 grams of something--decently heavy for solder--should last you a while

  • SomeGuy123 / about 13 years ago * / 1

    You actually aren't likely to get lead poisoning from lead solder.
    Lead poisoning usually occurs from contact with lead acid and lead salts.

    • Comrad_Durandal / about 13 years ago / 1

      I'd imagine it's the case of CYA. The average hobbyist isn't going to get heavy metal poisoning from using lead solder, especially if they are careful, minimize exposure, don't ingest anything while soldering, and washing their hands and exposed body surfaces with soap, hot water, and a nylon brush thoroughly (more than a minute) when they are finished. However, lead (like other heavy metals) are -cumulative- exposure, which means it builds up in your system over your lifetime.

  • Paolo Mosna / about 13 years ago / 1

    Does anyone know the wire diameter?

  • bsiegel / about 14 years ago / 1

    Be careful, I ordered this and received a spool of 63/37 solder instead of the 60/40 as is claimed.

    • Member #399312 / about 11 years ago / 2

      It is claimed to be 63/37

    • The description states that its a 63/37 mix.

    • 63/37 is better anyways! At least IMO... fewer cold joints and any electrical/strengths losses aren't really noticeable.
      Just an opinion :/

    • Member #377364 / about 10 years ago / 1

      63/37 is eutectic (google it), so the Pb/Sn alloy melts nicely at the lowest possible temperature.

      I just picked up two spools of this for a super low price...thanks, SparkFun!

    • BB / about 13 years ago / 1

      You should be thankful. 60/40 is crap.

      • 6strings / about 10 years ago / 1

        You said it best. 60/40 is crap compared to 63/37. This is good solder.

  • Bfloberg / about 14 years ago / 1

    The description says 100grams ;)

  • Nadav Ami / about 15 years ago / 1

    Does anyone know how many grams of solder are in the spool?

Customer Reviews

4.3 out of 5

Based on 3 ratings:

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1 of 1 found this helpful:

0.031 Leaded Solder 63/37 resin core

Exactly the right diameter. Works perfectly!

63/37 perfect alloy

I get nice shining solder joints. I'd prefer a 1lb spool. I like to have abundant amounts of solder around, however, keeping low pricing like you do keeps me coming back to your site.


For the price, it is good.