Tin Plating Powder

[Trevor Rymell]

Has anyone used Farnell tin plating powder?

I recently bought a 450gm pack from Farnell. The instructions say to mix it with 5 litres of water but do not say how much to use for a given size of board.

Can anyone tell me how much you are supposed to use to plate a PCB - all of the 5 litres or just enough to immerse the board?

Thanks

Trevor

 

[justDIY]

its not all that precise ... just fill a plastic dish with enough water to soak your boards in ... and then start dissolving powder until you achieve the desired effect. have some sealable glass jars ready to save your solution for the next board (if you don't have small kids / siblings, stick them in the fridge labeled poison)

some formula specify hot water, or heating the solution ... so double check your instructions for this as well.

 

[Trevor Rymell]

JustDIY

Many thanks for the reply.

I suppose the "desired effect" is an even tin coating over all the tracks. I don't know as I've never used it before. The instructions with the Farnell stuff say to dissolve the whole 450gm in 5 litres of water at 50c then let it cool to room temp after which it's ready for use. I had thought I would follow that method using just enough to soak the boards in each time.

I have no idea how long you're supposed to leave ther board in or if I can use the same smaller quantity several times before I have to dump it.

Regards
Trevor

its not all that precise ... just fill a plastic dish with enough water to soak your boards in ... and then start dissolving powder until you achieve the desired effect. have some sealable glass jars ready to save your solution for the next board (if you don't have small kids / siblings, stick them in the fridge labeled poison)

some formula specify hot water, or heating the solution ... so double check your instructions for this as well.

 

[justDIY]

I dont recall how long it takes either, it was some time ago... but yea, once all the copper has turned silver, you're done

here's an alternate method ... say you only want 1 l of water, so you need 90 mg of the powder assuming the powder is homogenous (450 / 5 = 90) ... that is 90mg by weight, not volume, so you'll need a balance or similar small scale to make sure you have the right amount.

 

[Hero999]

Also don't just dump it (that could be illegal) it needs to be disposed of in the correct manner, the chances are your local tip will have a section for you to dispose of chemical in.

 

[Trevor Rymell]

JustDIY, Hero999

Many thanks for the replies.

Trevor

 

[mramos1]

Trevor.

You can re-use it and for quite some time, and mine is stored in a hot garage..

Only use a little and seal up the power and like DIY said, the liquid in a glass jar when you are done. Maybe take a test piece of copper and try that first. With mine, premixed, I shake it and looks like a little white milling sand is in it.

 

[Trevor Rymell]

mramos1

Thanks for the reply. I'm clear now and will do as suggested - mix 1 litre using 90gms and see how it goes. I'm looking forward to making some more professional looking boards. I used to just varnish them.

Regards

Trevor

 

[justDIY]

another tip for the "professional look" ... you can use the toner-transfer method to do a silkscreen layer ... after etching and plating ... print out and iron on your tDocument layer

to a lesser degree, the blue toner transfer sheets will make a faux solder mask ... not really all that useful, but if you're looking to make an impressive looking board to show to clients

they also sell white and green film for iron on toner transfer ... you do the normal toner transfer, cover the board with the white or green film, and rub ... powder in the film only sticks to the toner and dies it white or green (for silk / mask)

 

[chemelec]

An Electro-less Nickel Plating Solution Give a Much Better coating.
It doesn't oxide near as much as the Tin coating and solder very nicely.

Unfortunately it is expensive and harder to obtain.

You just heat up the solution and place your Cleaned boards in it till you get the thickness you want.

As to the Tin Coating or any coating, Make Sure your Boards have Nice Clean Shiny Copper, GREASE FREE.