How to prepare pads on ic beffore reball

[ktmmotocross]

Hello.
I have some problems on some intel ic to prepare pads for new balls. wheen i try to put some solder with iron on it it just dont want to.
i using kingbo past.

[highpulse]

Re: How to prepare pads on ic beffore reball

well use it well using good goodwick , and a good hot temperature , i usually scratch a bit does very dark pads , then i scratch them gently with gootwick soaped in tin lead