Solder not melting... Ugh! Help!

[joyride]

Bought soldering iron that heats up to 480 degreses.
Working on resistor on my LG plasma 50 inch PSU

So I let it heat up, then put a copper strip between the resistor "nipple" and the iron.
After doing that a bit, i put the iron directly on the resistor "nipple"
Doing that has malformed the nipple some, but simply wont melt it so I can "suck it" up with my vacuum pump.

This is really frusterating. Any advice much appreciated!

[mariushm]

Re: Solder not melting... Ugh! Help!

Add flux and a bit of leaded solder at the joint.

[budm]

Re: Solder not melting... Ugh! Help!

What is the Wattage of this soldering Iron? it should be 40~60 Watts range.

[joyride]

Re: Solder not melting... Ugh! Help!

"Add flux and a bit of leaded solder at the joint."

Can you dumb this part down some?What do you mean? And I have lead-free solder will that work?

....Also my soldering iron is 60 watts...

[budm]

Re: Solder not melting... Ugh! Help!

Do not use the lead-free solder, just melt the regular Lead/Tin solder to the joints and then remove the solder from the joints using solder sucker or solderwick. Do you have liquid flux?

[mariushm]

Re: Solder not melting... Ugh! Help!

The surface where you put the tip may be oxidized which is sort of like a shield blocking the heat from the tip warming up the solder on the board and the component leads, it's basically turning your 60w iron into a 10-20w iron.
Flux when warmed up by the iron tip attacks the oxides on the surface and "breaks" them down.
You can buy flux in the form of flux pens, bottle of flux, a sort of cream etc etc... basically put some flux on the surface and approach the solder iron tip.. as it heats up the flux becomes acidic and corrodes the thin layer of oxides at the top.

After that, you can put the iron tip to the component lead or on the hole add add a bit of solder at the point the tip meets the other metal. This solder will help transfer the heat from the tip into the copper on the pcb and the lead.
Most solder wires have some flux in them so most times it's enough to just put the solder iron tip on the lead/pcb base and insert the solder wire there - the flux in the center of the solder wire will melt first and spread over the surface and clean it a bit which would then allow the solder to spread and warm the already existing solder allowing you to suck everything up... but if you want the whole process to work faster/easier it really helps to add some flux separately.


See this video, explains all about flux and solder types and how soldering works .. though dated the information is still valid : http://www.youtube.com/watch?v=vIT4ra6Mo0s

[retiredcaps]

Re: Solder not melting... Ugh! Help!

See this video, explains all about flux and solder types and how soldering works .. though dated the information is still valid : http://www.youtube.com/watch?v=vIT4ra6Mo0s

+1 on the paceworldwide videos. They are excellent.

CuriousInventor, another favourite of mine, just posted this recently

"How to Desolder Through-Hole Parts, Why Some Joints are Difficult"

http://www.youtube.com/watch?v=Z38WsZFmq8E

[HAHOMETP]

Re: Solder not melting... Ugh! Help!

My two favourite fluxes:
1. Deoxit Rosin Soldering Flux non spill RSF-R80-2 for everyday soldering:
http://www.cyberguys.com/images/prod_images/p77640a.jpg

2. Lenox lead-free water soluble flux WS78091 - for soldering older oxidised wires. Most of the time you can forgo scraping them with exacto knife.
http://img3.fastenal.com/productimages/0803406.jpg

[joyride]

Re: Solder not melting... Ugh! Help!

So it cannot be lead-free solder?

I covered the point in flux then brought iron close to the flux to heat it up...i then put lead free solder between the iron and the point...the point did not melt....

[tw2005]

Re: Solder not melting... Ugh! Help!

Post some pictures of the situation and someone may spot something.

[Th3_uN1Qu3]

Re: Solder not melting... Ugh! Help!

With lead free you need higher temps to melt the solder, which results in higher likelihood of damaged parts or cold joints (or solder not melting at all in youur case). That is why it is recommended to use leaded solder in most rework jobs.