Tinning?

[chutneyfarmer]

Heya,

I am waiting for the shop to reopen before I place an order for a handful of pcbs. I read on the forum that you are no longer tinning the pcbs that you send out.

Do the pcbs need to be tinned? What are the consequences of not tinning them? And if I was to tin them myself what would you recommend using?

Thanks

[pandadandan]

Heya,

I am waiting for the shop to reopen before I place an order for a handful of pcbs. I read on the forum that you are no longer tinning the pcbs that you send out.

Do the pcbs need to be tinned? What are the consequences of not tinning them? And if I was to tin them myself what would you recommend using?

Thanks

They don't need to be tinned at all IMO.  Madbean's PCBs are always polished to perfection, so there's no need to worry about making good electrical connections.

Tinning prevents oxidization of the copper to some degree, but this is irrelevant if you don't spend weeks soldering a PCB. 

I recommend that, upon reciept of the PCBs, you wrap the ones you're not going to work on in saran wrap/cling film without touching the copper surface.  When the time comes to solder, just rip off the protective wrapping and get to work.

[madbean]

The tinning thing was kind of a fad for me. It makes the PCB's look really good but as pandadandan said it's not necessary. Even without the tinning, the boards are polished with 000 steel wool first in a multi-directional pattern and then more deeply at an angle to create nice grooves to soak up solder. They are also cleaned with Acetone to remove residue before they are bagged.

The boards will begin to oxidize within a week or so, although not as much in the bags. If you have any discoloration over time, you can repeat the process I described to make them brand new.