Hello. We have a walk in the woods again today. I decided to just walk around.
Standing static, I think many people do not like these talking heads, they often infuriate everyone))
In today's video, we will talk to you, or rather I’ll tell you, about how best to build cleaning processes PCB.
and what they depend on ... in your factories - small and large.
And for this, we will immediately divide the technical processes into water-soluble and water-nosoluble, so that it is easier to understand.
Water-nosoluble, the so-called No Clean, their residues after soldering on the board do not cause any harm to it,
but aesthetically, they, yes, will look like dried puddles. Sometimes customers don't like it, they even demand no-clean wash.
And NO Clean fluxes are washed, no matter whether it is manual soldering or the soldering paste was NO Clean, such a flux is washed only with reagents, liquids, such as Vigon FA + for ultrasound, or Vigon EFM for manual cleaning.
There are a lot of different liquids. I mainly work with Vigon. Vigon A250, SC200. There are a lot of different liquids.
Liquids - reagents are just intended for cleaning.
So that the board is completely clean and not dirty. To do this, the technical process must be adapted from the very beginning.
That is, if we use No Clean fluxes, No Clean soldering pastes, then we need to immediately think about
how we will hand them over to the customer. We will wash them before handing over to the customer, or we will not wash them -
leave the printed circuit boards as they are, and for this, of course, you need to negotiate with the customer of your printed circuit boards.
And so you can save on liquids without cleaning the circuit boards. And this is a very big expense.
In reality, when it is necessary to launder large batches of printed circuit boards, this is a very big economic problem for many.
And therefore, it is imperative to resolve the issue with washing before you take a batch of boards to work.
Many printed circuit boards, for example LED PCBs, do not have to be washed and there are often no cleaning requirements.
At the same time, aesthetically, there will be traces of the flux.
We had 1 technical process. Now I'll tell you about water cleaning - water-washing fluxes, water-soluble fluxes. These are all those fluxes that
are found in tubular solders, in solder pastes. Flux for hand application - 1095, for manual work.
For selective soldering, it seems to be suitable too.
To wash off the water-washable flux, you just need a bath with distilled water with bubbling.
Water Clean fluxes can be washed with water. They have a major difference from No Clean fluxes ...
They must be washed off! They should never be left on the PCB with WC fluxes.
That is, the water-soluble flux must be washed off. But at the same time we save on the reagent - liquid.
We do not spend on the reagent. We wash PCBs with plain water - naturally distilled water. Not from the tap!
At the same time, we do not waste any special reagent liquids, we just change the water.
Many have distillers - an inexpensive pleasure. You can wash perfectly with water and the printed circuit boards will be clean,
but you need to immediately understand - if we wash only with water, then we need to use water-washable soldering paste,
tubular water-washable solder, so that we could immediately wash everything with plain water.
And any residues of water-washable fluxes on the PCB will cause corrosion, oxides.
The halogens in these fluxes can cause serious damage to the PCB.
Therefore, flush flux must be rinsed off. How does this happen in many enterprises?
Usually they solder No Clean with solder pastes, smd installation was quickly done, assembled, and then we have DIP installation,
these are output components - pins, connectors. DIP soldering is not clear how.
Many do not even bother to delve into what they solder and how to wash it later.
There are cases when ordinary installers, there can be many of them,
they do not even look at the technological maps. They do not understand what to be guided by. What you need to solder.
They took what is at hand, soldered, and what happens next to this printed circuit board, they no longer care.
And in order to avoid this, you just need to prescribe from the very beginning, as soon as you took a jar of solder paste,
think over the entire technical process of assembling your printed circuit board to that end - before cleaning, so that there will be no problems later.
By the way, rosin fluxes - RMA, these are all No Clean fluxes, that is, they cannot be washed with plain water.
To do this, you need to either wash with alcohol-gasoline mixtures, as we often like to do, or with foreign reagents.
RMA flux is harmless to PCB. These are mainly ROL0 fluxes.
They are, of course, different, you need to watch and check all this when you buy them.
Any flux, for example ORH1, these are all water-washable fluxes, they contain halogens.
For example, we took No Clean solder paste, soldered the printed circuit board, even if it is not washed, then nothing will happen to it.
Yes, it will be aesthetically dirty, but nothing will happen to it. Then we take DIP installation and take water-wash flux,
solder all DIP components and send it to wash. The printed circuit board will be washed, but partially.
That is, where there was a water-flushing flux, all its residues will be washed off with plain water, and all those residues that
remained from No Clean are rosin residues, they remain there. They crystallize and
stay on the board for the rest of the life of the circuit board. This does not suit many.
Therefore, think over everything from the very beginning. That is, you either use No Clean fluxes and you do not wash them, like LED for example.
Or you wash it if it's some kind of high-tech printed circuit board.
Then wash it off with a reagent. It will not wash off with plain water, do not even try.
Or we choose the second option - water-wash materials. Water-washable solder paste,
water- washable tubular solder and finally distilled water. First wash - 50 degrees,
then rinse 50 degrees. It's simple) Be sure to put your thumbs up, subscribe to the channel!
Ask your questions, if any, and they definitely are. Under the video you will find a link to my site
for SMD installation, production consultations and electronics development. Bye Bye)