Tinning an etched PCB

[Herath]

Hi all,
I have seen liquid(not melted tin ) tin on internet (also available in powder form) which could be used to coat tin over copper paths on a PCB to prevent oxidization.
Have anyone in robot.lk used them?. I read that they helps a bit when hand-soldering SMD components.

Here is an example.
Tinning solution powder at Ebay

[Magneto]

Dear Friend ,
I am not sure about this particular Tin based solder Liquid. But normally solder flux liquids are used for quality soldering. It Helps solder to "cling" to metal by removing oxide buildup. Also helps spread out solder by reducing surface tension. Liquid flux is crucial for surface mount soldering and de-soldering, but usually not necessary for through-hole components.

I called to a friend in TOSS Lanka ( Largest surface mount soldering company in Sri Lanka) , before answering to you, he said they are using some flux liquid , which is importing from Japan. All the labels in that bottle have written in Japanese language ,so he could not find , whether that liquid contain Tin.

Note: When applying any type of flux, apply as little flux as possible because the residues can be corrosive, conductive, and sticky.


Regards

[Saman]

We didn't want to do tinning for our personal projects which we do solely for experimental purposes. However, this is used for mass scale PCB manufacturing. As Magneto stated, it should be kind of tinning solution that TOSS guys are using.

Have a look at this video that demonstrate the tinning process.
[media]http://www.youtube.com/watch?v=frsDN7usyCs[/media]

See the usual way we do
[media]http://www.youtube.com/watch?v=i32f5_0hXQU[/media]

[Herath]

Hi, thanks for the reply..

Have look at if you have some free time (tinning start at about 4 mins) .
[media]http://www.youtube.com/watch?v=3aEwTRMEkOM[/media]
The guy is using a tin solution. The solution contains Thiourea and tin chloride as for my memory. Putting the PCB in the solution will coat tin over the copper paths of the PCB.

I have read about soldering flux and have had had lot of problems with having to solder electronics without them. (de-laminating the PCB by overheating .. etc ). I have only used soldering wires with a flux core till now. But I will buy some soldering flux for SMD soldering.

PCB manufacturers might not use tinning since they can use a solder mask easily instead of having to go through this process. It is nice looking and better. I am thinking of tinning the PCB since I can't have a solder mask if I am going to make my own PCB.

[Herath]

Hi Saman,
Thanks for the videos. I watched them. Sometimes I am thinking about getting the PCB done from a ebay PCB manufacturing service, but that's going to cost about 50US$. That's why I am thinking about making the PCB by my self. I can handle the chemicals etc. I have some practical knowledge from university lab classes.

Thanks