How to solder correctly (a not so brief lesson) Plus tips and more...

[togy]

Originally Posted by Marine6680

Yeah... Start with a small tip (try your best to get it task appropriate in size, with relation to the part and circuit trace) and start on low temp about 600*F. Then see how that works and adjust from there.

Use a third hand device if needed. Also keep the iron tip out of direct contact with the board substrate material as much as possible, to minimize damage to it.

Get a magnifying lamp, that will help see the small components.

In the end a steady hand will be your friend.

Thank you. I have a pencil shaped tip but I still find it very hard. I get bridges of tin between the poles and I have a hard time making the wires not move when I touch them with the iron. I usually solder the wires on top of the old solder. Should I try to remove the old solder and put the wires through the PCB or what's the best way?

[Marine6680]

If you can remove the old solder and use the hole, that is best.

If not, removing some solder will help keep things steady, and you can add fresh solder to the joint. This will help reduce the amount of solder and help prevent bridging.

I have a strong dislike of pencil tips myself. I prefer chisel or flat blade tips. (one flat side, or ones like a flat tipped screwdriver) They hold on to solder better and help pull excess solder away from the joint, while round tips will not. They can;t prevent you from heavy handed and applying a large amount, but small excesses can be managed.

[togy]

Thank you very much, I'll try those things next time I solder!

[al93535]

Wow! First time I've used my new TK 950 on a real project. Just soldered 3 5.5 mm bullets to 10 Guage wires, and WOW!! What a breeze, what a pleasure, why didn't I get this before? Also used my new 67/33 solder.

Getting ready and excited to solder the 8 Guage wires onto my dean's.

Quality equipment makes more then a world of difference, it's unbelievable!

sent from a non Apple device

[Marine6680]

Glad to hear it worked out for you.

[Fastrack]

Hi,

I normally hang out on rcgroups so first time poster here. But I found this thread as I need to solder 3.5mm bullets for my quad. I've been using 63/37 solder with 377 flux for many years but it's 1.23mm dia(.0484 inches)

I'm looking at buying Mg chemical mentioned earlier in the thread that comes in .025" and .032" and up. http://www.mgchemicals.com/products/...sn63-pb37-4880

As for flux, I've never used it(except on plumbing.. Lol). Mg chemical makes a rosin flux
http://www.mgchemicals.com/products/...osin-flux-835/

For leaded and lead free soldering. Fully activated. Offers superior fluxing ability. Instant wetting. After soldering, the rosin residue is non-corrosive, non-conductive, moisture and fungus resistant.
Superior fluxing ability
Instant wetting
After soldering, the rosin residue is non-corrosive, non-conducting, moisture resistant, and fungus resistant
Meets Mil. spec. #RA 14256
ANSI Spec. 004
ROMI class, J Standard
RoHS Compliant

Some sites have a picture of the bottle that says no clean on the label... But you have said no clean does not work as well. It doesn't look like RMA type flux is available in Canada, digikey doesn't even sell it. Does the above sound like no clean?.. Really confused!

Thanks,

Ben

[jbobb1]

This is what I've been using.

http://sra-solder.com/product.php?xProd=7039

[Krazie Sj]

Had to do some soldering in my truck for an illuminated 4x4 switch. I read and reread your posts on soldering properly. Just wanted to say Thank-you for the tips and insight. They really helped make it a much less frustrating process.

[Marine6680]

Yahoo only just now informed me of replies.


Fastrack: That flux looks like activated rosin flux. Its stronger than RMA. It will work, just clean it up well after.

Krazie: Glad it helped.

[Felix the cat]

Speaking of replies, guess better late than never.

Yup ! It was the solder, changed it as you suggested and having a much easier time with my connectors and boards.

Gracias.

[Marine6680]

Slow replies all around.

[Nitrofish]

Awesome. Thanks for sharing!

[Fastrack]

Originally Posted by Marine6680

Yahoo only just now informed me of replies.


Fastrack: That flux looks like activated rosin flux. Its stronger than RMA. It will work, just clean it up well after.

Krazie: Glad it helped.

Yeah your right. I couldn't find RMA solder in Canada. So I bought the solder and flux I linked too. I cleaned up the parts after soldering.

However putting new ends on my battery 10g wires pushed me over the edge - solder wicked up the wires about 3/4". The weller wlc100 (I've had it for about 10 years) has been replaced by a Hakko fx888d. I can not believe how fast it heats up. I haven't tried soldering yet.. I did tin an 18g wire that was giving issues before and no melting insulation! The tinning didn't even go the insulation like it always did before, I have 3.2mm chisel tip (and various other ones) for the weller (there's only one bigger tip), but the heat was sucked out so quickly that it required so much contact time (like you described)

Ben

[Marine6680]

Glad you have it figured out.

Enjoy the new iron.

[Fastrack]

Originally Posted by Marine6680

Glad you have it figured out.

Enjoy the new iron.

Finally did some soldering with the new iron. It heats up in about 20 seconds. It's magical

Question for joining wires.. Do you use a lap joint or a western union splice? I've always used a western union splice or a slight variation of it.

However I was doing very small wires about 28 gauge and the lap joint worked so well, I was thinking.. What is the real down side? Normally I heat shrink both connections and a big piece over the joint.. Is solder (unless it's a cold solder joint) going to break?? A lap joint is used when soldering to deans or XT60 connectors so what is the down side?

I read most of your topic on RCTech so if you mentioned this I missed it.

Great topic btw

Let me know,

Ben

[Marine6680]

Since I can not edit the OP...

How to remove solder if you make a mistake:

Solder wick, a strand of braided copper, can be used to soak up solder. You use it by heating it and the solder with the iron, and it wicks up the solder. It is not good for large amounts of solder, as it takes a lot of wick.

There are several vacuum solder removers available. Some spring loaded and others are a bulb type. You use it by melting the solder and then using the tool to suck up the solder. They can get much of the solder off the area, and work for large amounts, they don't do well with small amounts.

I like to use both to clean up connections. The vacuum first, then the wick to clean up the last of it.

There is also vacuum solder removers that are heated like an iron and connect to a vacuum pump. They work awesomely, but are expensive. Most RC soldering will not see a need for such a thing... but they are nice if you have access to one.

[crack]

very nice info thank you

[Oreca]

Hello guys,

I'm a bit anxious when it comes to cold solder joints. Read a lot and it's scaring me a bit, don't want to loose my bird due a bad solder joint.

I did some bullets for my 550X, but the ESC wires were a bit bigger then the bullets. I shave some off but had a hard time putting it in. Solder it, solder it again and put more solder on it etc...

I did some visual and testing for the soldered wires. If the results are good, what is the chance that it is a cold solder joint?

-I tried to pull the wire and the connector apart very hard, still solid connection
-I measured the wire only with resistance multimeter (no voltage applied), came out 0.4 ohms. I then did the wire to the end of the bullet and it was still 0.4 ohms.
- I checked the solder joint, looks like it is shiny, can't see in the bullet ofcourse.

[Helique]

Hi All:
Just thought I'd post these photos of my home made "helping hands" soldering jig. It's just two clothes pins glued to a piece of scrap wood. Of course it doesn't work as a heat sink but it's handy in a situation where you don't want metal alligator clips distorting the plastic insulation on the wires.

[Marine6680]

Nice... Things like that can really help.


Apparently the site did not inform me of the other poster... And now it's almost a year too late.

Cold solder joints are usually detected visually. A cold solder joint will look uneven and not smooth like the solder flowed easily.

Cold solder joints are cause by the solder wanting to partially solidify while it flows through the wire and part. This can cause the solder to not bond with the metal surface very well.

They can also be caused by disturbing the joint during the transitional plastic phase from liquid to solid. This is why I recommend 63/37 solder, as it does not have this plastic phase.