Why is soldering so difficult?

[t3yf5g]

Okay, I think this is good.




After grinding the tip, the solder did float nice on the tip. Then got the flux on the wire and solder flowed right in. The dabbed some solder on the terminals and pressed the two together.




Now I am not so confident on my BEC soldering. Only because I soldered the wire in between deans connectors. If the soldering is bad, then I get bad connection from the battery to the ESC and motor. It's wrapped up in electrical tape over some shrink wrap that didn't fully fit.

[malibulvr]

Looking at your motor joints I would still get a new tip. It looks like you may still be having problems with heat transfer or maybe the motor tabs weren't cleaned off enough. The solder should have a better flow to it and not look like a ball at all. Did you tin the motor tabs before you soldered your wire?

[Draggermirage]

For what reasons do you guys use an external source of flux and non-electrical solder?

The Rosin core solder functions MUCH better than the clean > flux > Tin > solder method.

You don't need to jack around with anything other than tip temperature, tinning and steady hands.

Do yourself a favor and save the flux for soldering chassis rails together and other non-electrical uses. My favorite solder so far is the 60/40 tin/lead Radio Shack Rosin core electrical solder. I do not use any silver bearing solders as the joints tend to turn out cold much easier and is generally harder to use.

Marcus

[ik632]

When I solder wires into the "U" shaped slots like that I like to tin the wire and then tin the slot. After that, stick the wire in the slot and press down on it with the iron. It should heat it up enough to melt and then melt the solder on the tab. You should not be putting solder on the tip to transfer to the joint. I always wipe the tip before soldering and may add just a little to the tip as it's pressing against the wire to help heat transfer.

If you need more solder in the joint, keep the iron on the wire, putting pressure on the wire into the slot, and feed in some solder with your spare hand. You should feed the solder into the wire just above the slots and let it melt and wick into the joint. This should all happen pretty quickly because if you put too much heat onto the tabs it could melt something in the motor. This is why I like to press on the wire so it melts (and I don't really care how hot the wire gets since it has silicon sheathing) and let that heat melt the solder on the tab.

Ideally I'd like to see the top of that joint look like the wire with solder on it (so you can still see the stands of wire but they are covered).

[ik632]

Here's a picture of through hole mounting. See how the solder is flat and shiny:



I could have actually used a little more solder on the two right tabs, you can see a tiny gap below the wire, but it's soldered about 270 degrees around so I'm happy. My own personal goal is to use as little solder as possible to join things together. I even have some desoldering braid I use from time to time when I overdo it.

[bob1961]

i have a HAKKO 936 and every time i use it i wipe the tip off so it's clean....i use radio shack 60/40 rosin core solder as well....every time i pick up the iron i wipe it with the wet sponge before i tin it, then i tin what i'm bout to solder then i wipe the tip on sponge and back into the holder till next use....when done i turn off iron and keep wiping the rosin from solder off the tip to clean it untill it is cool and never have had any issue with a dirty tip from the rosin in the solder........bob

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[t3yf5g]

Well I do have more practice to do. Everything runs so I am happy for this go around. When I get another rig to build, I will have another go at it and try to use less solder.

[AreCee]

That is correct that you don't want to see a big blob of solder ON TOP of the work. You want it to flow INTO the work, it should be shiny and look like wire strands.

Using flux just insures that any oxidation is removed prior to making the joint. The rosin core solder is good but if left on the tip tends to evaporate quickly. I brush a little flux on the work right after I tin it so the joint is clean and free of oxidation. If I'm adding additional solder I let the rosin core be the flux but when joining to pre-tinned items I use a dab of flux.

[badhoopty]

Originally Posted by AreCee

That is correct that you don't want to see a big blob of solder ON TOP of the work. You want it to flow INTO the work, it should be shiny and look like wire strands.

Using flux just insures that any oxidation is removed prior to making the joint. The rosin core solder is good but if left on the tip tends to evaporate quickly. I brush a little flux on the work right after I tin it so the joint is clean and free of oxidation. If I'm adding additional solder I let the rosin core be the flux but when joining to pre-tinned items I use a dab of flux.

i use flux regardless of tinning or soldering tinned pieces together. i just find it a whole hell of alot easier to flow the solder when i use paste or liquid flux.