Soldering and SMD

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I'm curious if anyone mind giving me some advice on soldering irons. I've been using a Weller WESD51 as a student and hobbyist with good results.

I've been moving more and more into just using SMD components that I'm wondering if I should upgrade my soldering iron.

Is there a difference between soldering irons and rework stations? From the info I've seen rework stations are more useful for SMD devices.

Can anyone recommend me a decent upgrade? (not professional grade but decent)

I've also seen videos online of a "hoof" tip used to solder SMD components. I've searched but haven't gotten much luck. Does Weller call it something else?

Thanks for your advice
- Emmanuel

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AFAIK, only Metcal and JBC make hoof and mini-hoof tips, but I could be wrong.

You can make do with a suitable chisel bit by putting a small blob of solder on it. Plenty of jelly flux is the secret. It won't be as good as a mini-hoof tip, but it should get the job done, with a few more solder bridges being likely.

Leon Heller G1HSM

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emmannuel wrote:
I'm curious if anyone mind giving me some advice on soldering irons.

Patience, a steady hand, good eyes, good magnifying lens, good lighting, small soldering tip, fine pitch solder (0.015"), good quality solder wick, solder flux and lots and lots and lots of practice!

But the real challenge is, changing your mindset regarding SMT over conventional thru-hole soldering! After you accept challenges STM brings to the table, the real advantages of SMT become apparent.

You can avoid reality, for a while.  But you can't avoid the consequences of reality! - C.W. Livingston

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I don't think I've ran into the jelly flux. I'm using a liquid flux rosin which has helped but can be a bit messy. It makes my fingertips incredibly sticky.

Thanks for the advice Leon and Carl.

I really do enjoy the advantages of SMD components. Sadly I am seeing that I don't always get get to make the choice. I'm noticing a lot of the newer parts are not available in through hole packages.

I've had a funny case recently where I thought I fully soldered all the 8 pins on a SOIC chip. When I lifted the board it slid right off.. :(

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This is the jelly flux I use:

http://www.warton-metals.co.uk/re-work.html

Leon Heller G1HSM

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SOIC is quite trivial :) The real fun starts with 0402 and 0.5mm pitched pins ;)

Flux is very important but the stickyness can be annoying. A flux dispenser bottle can be handy.

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mmmm stiiicky fluuxxx

Homer

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jayjay1974 wrote:
SOIC is quite trivial :) The real fun starts with 0402 and 0.5mm pitched pins ;)

Flux is very important but the stickyness can be annoying. A flux dispenser bottle can be handy.

Psh - the real fun is when you try to do BGAs.

As for fluxes - they are essential. I like to have a good selection of fluxes. A liquid no clean and a gel are both important to have, in my book. Digi-Key sells both.

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I use solder paste. Sparingly applied it will hold the component in place and all you do is reflow it with a nice broad tip. With a 16 pin SOIC I do two leads at once and it is all over in 20 secs.
A suggestion is to get practice with an old board. Heat a board with lots of SMD's that you want to practice with a Heat gun. The bits will fall off when you give the board a flick/tap on a work bench. Solder the components back for practice.
There are some SMD components like BGA's that are impractical to do unless you have the right gear.

As far as a rework station, the major features of it are the component removal/de-soldering facilities rather than the soldering facilities.

Charles Darwin, Lord Kelvin & Murphy are always lurking about!
Lee -.-
Riddle me this...How did the serpent move around before the fall?

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Practice, practice and more practice...
I use solder past, before I had been use flux but now only solder past but not for all components only for the small ones...
After I went to a assembler company that doesn't use anyone of this.... ;)... I change my thoughts about it...

Regards,

Bruno Muswieck

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Flux should be cleaned with isopropyl alcohol right?

Thanks all for your input

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Alot of it, yes, but many are advertised as either "no clean", which means poor conductive properties and non-acidic, or "water clean", which means exactly that. I use IPA 'cause it makes me feel funny.

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As far as sticky fingers goes, I use a round toothpick. Let's me put just the right coating.

The largest known prime number: 282589933-1

Without adult supervision.

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LDEVRIES wrote:
There are some SMD components like BGA's that are impractical to do unless you have the right gear.
I mentioned my "fear" of BGAs to a technician;
his response was "I use a hot air gun"!
There are some awesome technicians out there.

"Dare to be naïve." - Buckminster Fuller

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emmannuel wrote:
Flux should be cleaned with isopropyl alcohol right?
An alternative is a non-flammable flux remover:
http://www.techspray.com/fluxremovers.htm

"Dare to be naïve." - Buckminster Fuller

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The main constituent, 1,2-trans dichloroethylene, is very inflammable:

http://msds.chem.ox.ac.uk/DI/trans-1,2-dichloroethylene.html

It needs to be used carefully, unlike IPA.

Leon Heller G1HSM

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Paint thinner works very well too, I used to immerse whole boards into a bath of it. Must be done outside really :)

Full immersion works better then brushing, I found that otherwise the flux dissolves, only to be deposited somewhere else on the board leaving a sticky film all over the board.

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I used to use paint thinners (xylene), as well. I left the boards to soak for a few minutes, then brushed them with a little clean xylene. It worked very well.

Leon Heller G1HSM