Just curious how many of you that make your own pcb’s actually tin them after they are etched? I know that tinning the traces and pads etc is supposed to protect the copper from oxidation and corrosion. But is it really necessary. And besides the pros are there any cons to doing it? I have some Tinnit and also some Liquid Tin somewhere but have to dig around to find it. Also, I just bought the stuff to make my own tinning solution in case I think it’s something I should do. Here is the link:
https://www.youtube.com/watch?v=Hsw3lOnHaas
I always tin all my boards every time (no exception). If you don’t tin them the traces oxidize horribly (in no time at all) and if you have to make repairs or modifications to a particular board it makes soldering next to impossible to do unless you start scrubbing the oxidation first. Now, when it comes to using solder mask well… I never bothered with it since “to me” for a little home made PCB is actually a waste of time and I like them better without it since all traces are clearer to see and follow. My take…
As we can’t buy that stuff over here I coat the solder pads with a rosin flux pen if I not soldering it the same day. It forms a protective layer.
When in doubt use a microcontroller.
That is good to know so I will make it a habit of doing it to all my boards as it isn’t really hard to do. My little projects are small and insignificant and in the past once I made a simple prototype I sent the files out and had them professionally made. Of course that won’t always be the case. Do you use Tinnit (powder) or the MG Chemicals Liquid Tin? That stuff is getting pricey but it is reusable and lasts a long time.
I always tin all my boards every time (no exception). If you don’t tin them the traces oxidize horribly (in no time at all) and if you have to make repairs or modifications to a particular board it makes soldering next to impossible to do unless you start scrubbing the oxidation first. Now, when it comes to using solder mask well… I never bothered with it since “to me” for a little home made PCB is actually a waste of time and I like them better without it since all traces are clearer to see and follow. My take…
As we can’t buy that stuff over here I coat the solder pads with a rosin flux pen if I not soldering it the same day. It forms a protective layer.
You must watch Electronics Repair School on YouTube. 😀 Sorin uses rosin flux for the same thing sometimes when doing repairs. I have a large amount of rosin and make my own liquid flux with it too. If you watch that video I posted above you can maybe get the stuff to make your own tinning solution. It uses Tarn-X which is a tarnixh remover from Amazon, and some mostly zinc solder wire.
@voltage I used to use liquid tin in the distant past but since is so bloody expensive and toxic well…I decided to develop my own method and that is: I make a mixture of liquid resin flux (the one MCL uses by MG Chemicals) and the SMD soldering paste (you know, the soldering paste that comes in a syringe style container and is used to solder all SMD components using the OVEN or the hot plate) and I always use the type containing at least 63-65 % Sn (Tin) and usually has a low (151 degrees Celsius) melting point. So I mix the 2 components together in very small quantities (only what I need at the time) and the resulting (sludge) I paint over the whole board but making sure the layer of that paint is as fine as possible. Then I heat up the board on a hot plate (or if the board is small enough) I ran the soldering iron over each trace in swift motions to melt the “sludge” and the result is a ticker layer on tin that will last forever basically.
Er….but there is a learning curve to do it right because if you apply too much sludge the resulting tinning effect is visibly uneven and is kind of… hard to get rid of the excess tin (perhaps using some de-soldering braided tape/wick etc.)since it sets pretty quickly and you don’t want to keep re-heating the traces over and over again in order to preserve their integrity!.
Now… this is my “personal choice” and I’m certain that this method won’t be appealing to many people since ….well…is a lot simpler to submerge the board in a “tinning solution” and you’re done in no time at all right?.
However….what I’ve discovered over time was that these commercially made (and perhaps even the home made) solutions have a “fairly short shelve life” and once you passed that, even though the tinning solution appears to still be working fine (at first Glantz) after a period of a few weeks to a few months the tinning layer appears to blacken up rapidly and at times it somehow oxidizes to such a degree that the copper (reddish color) starts to “transpire” thru the tinning layer and again not very “soldering friendly at all”. So, considering the above, I concluded that in my case doing it the way I do is my best bet and also the cheapest method of all that I’ve ever tried (so far)…however the most phiniky one… 😜.
@ovi4 Would the solder mask accomplish the same thing or would you still need to tin the traces if you were to use solder mask?
Solder mask expose the copper where you solder. Rest off PCB is covered with a protective layer.
When in doubt use a microcontroller.
@tone-c Wilhelm is right. At the industrial level (on how the PCB are made professionally) and as far as I know solder mask is applied directly on the bear copper traces and only and strictly on the area where you’ll need to solder there is no mask applied but tinning is applied instead so…to facilitate the soldering as well as to avoid copper rusting and degradation over time. However when (at the hobby “level” at home) we tin the whole trace then the solder mask (in my opinion) becomes redundant. But of course every individual has his own idea and can do whatever it pleases as long as the end result is satisfactory. 😎
@voltage I used to use liquid tin in the distant past but since is so bloody expensive and toxic well…I decided to develop my own method and that is: I make a mixture of liquid resin flux (the one MCL uses by MG Chemicals) and the SMD soldering paste (you know, the soldering paste that comes in a syringe style container and is used to solder all SMD components using the OVEN or the hot plate) and I always use the type containing at least 63-65 % Sn (Tin) and usually has a low (151 degrees Celsius) melting point. So I mix the 2 components together in very small quantities (only what I need at the time) and the resulting (sludge) I paint over the whole board but making sure the layer of that paint is as fine as possible. Then I heat up the board on a hot plate (or if the board is small enough) I ran the soldering iron over each trace in swift motions to melt the “sludge” and the result is a ticker layer on tin that will last forever basically.
Er….but there is a learning curve to do it right because if you apply too much sludge the resulting tinning effect is visibly uneven and is kind of… hard to get rid of the excess tin (perhaps using some de-soldering braided tape/wick etc.)since it sets pretty quickly and you don’t want to keep re-heating the traces over and over again in order to preserve their integrity!.
Now… this is my “personal choice” and I’m certain that this method won’t be appealing to many people since ….well…is a lot simpler to submerge the board in a “tinning solution” and you’re done in no time at all right?.
However….what I’ve discovered over time was that these commercially made (and perhaps even the home made) solutions have a “fairly short shelve life” and once you passed that, even though the tinning solution appears to still be working fine (at first Glantz) after a period of a few weeks to a few months the tinning layer appears to blacken up rapidly and at times it somehow oxidizes to such a degree that the copper (reddish color) starts to “transpire” thru the tinning layer and again not very “soldering friendly at all”. So, considering the above, I concluded that in my case doing it the way I do is my best bet and also the cheapest method of all that I’ve ever tried (so far)…however the most phiniky one… 😜.
Thanks for sharing your method. It’s interesting but you are correct in saying that would take some tinkering to get it to work 100% of the time. Looks like more work than I would like but it is still another way to do it. You are right as far as the MG Chemicals costing too much as when I priced it it is crazy how much they want for it nowadays. I am going to try the method in that video I posted above and see how that goes but I may see if I can find my tinning stuff from MG Chemicals first. 😋 In the video above the guy mentions that he has no idea on the shelf life but it is so easy to make it that you can mix up a batch as you need it. I bought a 4 pound block of 98 percent tin from ebay so I will have enough of the purest tin to make mine. 😀 That should make a big difference on the finished product. I think I bought too much but I always do.
Just a followup on the DIY tinning solution I linked to above. It WORKS! Very simple to make and I tinned an old pcb that didn’t turn out quite right for a test and it tinned it in seconds but I guess its best to leave it in the solution a few minutes for best results. The guy in the video say you can leave it in the solution for any amount of time as when the transfer of tin stops it won’t hurt anything. It is supposed to last a week or two so shelf life is a minor issue but I am 100% impressed. I used a 1 inch piece of plumbing lead free solder with 95% tin and 10ml (2 teaspoons) of muriatic acid in a small glass jar. Left it overnight and then poured off the clear liquid into a larger glass jar and added 3 ounces of the TarnX and stirred it together. I precipitated to a foamy substance that I could have heated to make it dissolve into a clear liquid but he said you don’t have to. I dipped my board into it and it transferred the tin almost immediately. Very happy with the results.
Nem szoktam be ónozni.
Szintelen akrilán lakkal lefújom vékonyan.
Fórrasztásnál sem okoz gondot.
A kész panel még 10 év után is szép, nem oxidált.
I tin by chemical because it is faster and it is 100% coverage.