Solder Choices

[Schroeder77]

This is my first post here. I've purchased a Crack which will soon be delivered, and I'm considering the best solder. 

In searching for balance between the easiest to use/best quality solder for this project, it seems Kester 44 63/37 (which makes it eutectic?) rosin core at a .031" diameter fits the bill.

Is this a good choice, and is the diameter appropriate?

I am grateful that there is a community for this kit building: I thought I'd be soldering alone, but now I see that soldering can be a joint effort.

I am so sorry for that. :-) I can't promise it's the last one either.

[debk]

LOL!

I use Kester solder

Debra

[Grainger49]

That sounds fine.  A small diameter solder allows you to put on how much you want to.  For me, large diameter solder heats up slowly and is always a blob when it liquifies.

[Schroeder77]

Thank you for your replies, I will now purchase it confidently.

 

[Paully]

I think you will be fine.  I just decided, in the end, to steer clear of silver solder.  Man that stuff can be hard to desolder if you mess something up.

[mcandmar]

You cant go wrong with Kester solder, using a cheap solder can be the most infuriating experience imaginable.

I bought a few meters of Cardas Quad Eutectic Silver solder to try and that stuff melts and flows like hot butter, virtually impossible to create a dry joint with it, just lovely shiny joints time after time. I was very impressed with it, but it does seem to have a lot of flux inside so lots of scrubbing is needed to clean the board after.  I haven't tried to unsolder any of it but i don't see why that would be an issue, if anything i think it has a lower melting point than regular 60/40.

Now led free solder, that is a royal PITA to unsolder...

[aragorn723]

Hi, I have a similar question, but am building a quickie.  The solder I have is Radio Shack rosin core 60/40.  Is that good for audio, or should I go with something more high-end?

[Paul Joppa]

I've used rosin-core 60/40 pretty much since the 3rd grade. It works great.

[Paully]

Well, Paul Joppa has already responded so I think you are set, but that Radio Shack 60/40 is what I have been using since I started and I have never felt a need to upgrade.

[aragorn723]

This is my first post here. I've purchased a Crack which will soon be delivered, and I'm considering the best solder. 

In searching for balance between the easiest to use/best quality solder for this project, it seems Kester 44 63/37 (which makes it eutectic?) rosin core at a .031" diameter fits the bill.

Is this a good choice, and is the diameter appropriate?

I am grateful that there is a community for this kit building: I thought I'd be soldering alone, but now I see that soldering can be a joint effort.

I am so sorry for that. :-) I can't promise it's the last one either.

Let's keep those dad jokes coming, lots of Dads around here i'm sure 

[aragorn723]

Well, Paul Joppa has already responded so I think you are set, but that Radio Shack 60/40 is what I have been using since I started and I have never felt a need to upgrade.

Thanks for the feedback, I wasn't sure if Radio Shack was up for the job.

[Schroeder77]

I have a followup question, just a bit divergent from my original thread topic . . .  Let's just upgrade the thread to "Solder(ing) Choices" in this case.

In my YouTube tutorial research, some people suggest putting a bit of solder on the tip of the iron a few moments before soldering each connection (called "tinning" the tip?). The primary justification was to better conduct the heat.

However, I saw another video of someone strongly suggesting not to do so, mainly because the rosin core burns away and throws off the balance of flux/solder. 

While both arguments seem plausible to a novice like me, I'm assuming the latter takes priority. Any opinions regarding this?

Also, here's what the Pace soldering training video seems to suggest the most of the process:

1. Heat to joint.
2. A bit of solder between heat and joint to "bridge"
3. Apply solder to other side, "painted on," allowing the flow to cover joint, remove while iron is still on
4. Pull away heat, do nothing (as in blow, let it move, etc.)

Steps 1-4 should take place within 2 seconds to avoid damaging the components.

Are there any additions, disagreements, or points of clarification that I seem to be missing here?

Should I instead make a new thread called "soldering technique?" I saw some related here threads that have been unused for quite some time.

Thanks again everybody!

[Paul Birkeland]

I don't really think it's necessary to tin the tip before each joint.  The amount of solder that it takes to tin the tip is generally pretty minimal compared to the solder used for your average solder joint (except maybe on a PC board).

Once you've done a joint or two, your iron should stay relatively tinned.

[mcandmar]

There are two sides to this, the first as pointed out above is to clean/prep the tip so its got a nice shiny layer of solder on it.  This only needs done once in a while, you can tell by looking at the tip as it will go dull when it needs refreshed.

The second which i suspect is what the articles are aiming for, is to aid the thermal transfer between the iron and parts you are soldering.   For example for something with a large thermal mass like the body of an RCA socket having a little pool of solder on the iron greatly increases the surface area for the iron to conduct heat though. With a dry iron you could end up holding it on the socket for minutes wondering why your solder wont melt. Even for small through hole components a small dab of solder on the tip can help heat the board and part evenly allowing you to get in and out quickly.

[Doc B.]

My suggestion is stop reading and start soldering. It's an eye-hand coordination skill that you have to master by repetition. As you solder more you will develop a feel for the thermodynamics involved and when you need to pre-tin, reflow, add more, take some away, etc.

My small contribution to overthinking it is to suggest that figuring out the best position for the tip of the iron to quickly inject heat into both surfaces is oft overlooked and, I think, one of the keys to success.