Stupid mistake

[mavrick0611]

Hi, a took some "advice" from my friend a while back about building a battery pack, i said something about would it be ok to put solder plux paste on it to give it a better hold? he said yes. I tried it one battery and solder would not stay on it. But i managaed to build the pack with it like that. its been about two months and today at that joint the solder fell off. i tried to redo it but its a no go.

I can see the blackish red stuff on the battery from were it melted. i tried getting it hot and whiping it off but it wont. So is there any way i can get it off? Sand it down realy carefully or something?

thanks

aj

[TA03 Drive Hard]

Did you add TOO much flux? you mean flux right? :confused: well if you did then ya try to sand it off carefully then try to apply it again... have your tried deans silver solder? cause it has flux in it and my packs stick well together ;)

[JP]

That Deans stuff is expensive, definately not worth the money. I use liquid flux that I got at my slotcar track. Its great, best flux ive ever tried. That other past flux is worthless, it makes it all acid-y. They also sell acid free flux...heard its good, but never tried it before.

[very low budget racer]

I got some silver solder and liquid flux from my LHS, It was one package and cost 8 dollars, not too bad. But from using paste flux previously there is no comparison, use liquid flux, you dont even need to grind the surface to get solder to stick, i made a roll cage with silder solder and liquid flux, i cleaned the joints with alcohol and didnt grind any parts, it was strong enough to bash with a hammer.

[mavrick0611]

could i use a dremel and lightly sand the old flux off?

aj

[rdockrey]

I disagree with JP. I just started using the Dean's solder and it works very well. My solder joints went from looking pretty bad to looking professional. I have found that you use less of it, so the cost equals out. Also, I used my dremel to remove some old solder on my batteries yesterday and it worked just fine. Just be very careful.

[mavrick0611]

i just used a dremel and stuck perfectly. thanks.

im using radio shack solder, it is a little hesitant to stay to the soldering iron, or be like a drop of water and cling to the biggest pile of solder. I would have picked up some better solder at my lhs, but they dont carry solder, or lathes, decent chargers, good radios, and i wont go on.

aj

[JP]

Did you coat (aww man im losing it, forgot the term) your iron? Keep pouring solder all over it until it stops "popping" and spitting out the solder, it should stick nice and well.

BTW - I have that Deans stuff. It works and is great and all, but WAY too expensive. I can get 15 times more solder for cheaper at Menards.

[jeepinator]

I have not used anything except Radio Shack rosin core solder for as long I can remember. My solder joints are very good. My biggest tip I can give you is HEAT !
The more the better. Get an iron with a big, heavy, massive tip on it. It needs to have staying power. And it needs to get HOT.
Batteries have a lot of mass and will cool normal tips real quick and you end up with "cold solder joints" (what happened to you). The flux (some call it rosin) is merely a heat conductor. It preps the surface a little, but it's primary job is to allow the heat to transfer from the iron tip, to whatever you are soldering. Without it, you will have huge problems. I just like to use the solder that has the rosin already in the solder (it runs down the center, hence "rosin core").
Anyway, good luck !

[DJ BlendeR]

I feel lucky, my LHS has this solder they sell for a buck and you sauder it on there and you can see the flux come out, it holds the wires on really good. Only thing is, you put the stuff on your contact and heat the contact instead of putting the solder on the tip of your saudering iron. Is this how everyone else does it?

[mavrick0611]

i use the Radio Shack rosin core solder too, it has that junk in it to? Did not know that... all of my joints have been great except for when i put the paste flux on that one cell, i dremeled it down and it stuck great this time. i need some more solder. I had other Radio Shack rosin core solder but i looked at it and it said for pc work, so it does me no good...

aj