Re: Precise solder paste application?

Hello,

I personally have never seen any individual stencil.
If they do exist, I would say that they can't work for the following
reasons.

1: It is impossible to use the squeegee on them as they would be too small.
2: They would also be impossible to align properly.
3: They would get in the way of surrounding components.
4: They would have to conform to the exact footprint used.
5: They would serve no purpose unless each coponet on the board is done in
that way and then reflowed.

Please enlighten me if I am wrong.

As I said originally, use solder and a good iron/tip. That will be the only
solution for hobby and it does work.


Regards
Ben



<a7yvm109gf5d1@xxxxxxxxxxx> wrote in message
news:1123770412.528741.44660@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> I'm no sure what the question really is, a lot of solder paste is
> applied by hand anyways when the operator uses the squeegee to apply
> paste through a stencil.
> If you are referring to single component work, why use paste? It's
> messy, hard to store and really not meant to work with an iron, but
> with a hot air pencil or reflow oven.
> Here's what I do when I install 0402 parts. I remove any previous
> solder with a good braid. Then I put some flux down (RMA). I use a
> run-of-the-mill Hakko 926 with 907 iron, and a small tip with a 45
> degree chisel (I don't have the number right now). I put a small blob
> of solder on the tip, surface tension makes it round. Then I put the
> part on the board, hold it down with some clean tweezers and just
> lightly tap each side with the solder blob. The flux ensures instant
> wetting, and by playing with the temperature and amount of solder, I
> manage to get great looking joints. Cleanup is with IPA.
> For ICs, it depends on the individual PCB, because sometimes there
> isn't any solder mask between pins, which makes it harder. I usually
> tend to "drag" a large chisel tip with lots of solder on it to apply
> solder to several pins at once. Again, lots of flux allows instant
> wetting and lets me get on and off the board quickly.
> If you must use paste, try buying some individual stencils, they let
> you apply paste to a single SOIC for example.
>


.

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