SMD Tips

[LED-FX]

Not plagarising but thought the following quotes from the PIC Basic mailing list might be of interest to a few around here.
(PIC Basic is a basic compiler by MELabs for programming PIC microcontrollers in case you wondered....)

"Sheperd Rudie,
Have a look at this site.
http://members.freemail.absa.co.za/faze/SMD.html

I'm hooked on SMT now - with some basic tools it's actually easier and
quicker than normal techniques!

Everything on the site isn't that clear - but I went to visit the owner and
he showed me his setup. I'm using SMT in the workshop for small projects all
the time now. Fell free to ask questions.

I use a little 12V compressor (the ones they use to inflate car tyres on the
road) for pressurizing the solder paste. I still use tweezers to handle the
components - can't find a vacuum pump yet. The best part for me (and you
have to see it to believe it!) is how you solder - just put a little paste
on each pad, place the components (no matter if they're a little skew), and
put the whole board on a conventional domestic iron! I turn it upside down
in a vice and set it to it's highest temperature (steam - but without the
water). After about 20 seconds or so the paste starts to melt, the
components centre themselves by "swimming" and the board is done!

Rudie
+++++++++++++++++++++++++++++++++++++++++++

Robert Atkinson,

Hi Shepherd,
For a vacuum pump have a look in your local pet shop or aquarium
supplier for one of the air pumps used to aerate fish tanks. These ate
cheap and suck as well as blow, you just need to connect a bit of pipe
to the inlet. I took an expensive commercial vacuum pencil unit apart
once and it had an identical pump!
Robert G8RPI

+++++++++++++++++++++++++++++++++++++++++

Ron L. Sparks,

A great vacuum pump is an old electric fuel pump from a car salvage yard.
Got mine for free. 12v is easy to find in my shop. Many of these pumps are
vane type so they are smooth.

Also, you can get some smt to DIP adapters at Mouser
(http://www.mouser.com). Look at the Aires Socket parts line.

Also look at "SurfBoards" products.

Ron
++++++++++++++++++++++++++++++++++++

This may open the door a bit for us with gorilla sized hands to get into SMT.

Adam

 

[lightuser]

And all this time I thought the SMD was an alternative sexual preference!

 

[jeff1500]

I have a couple of MAX1700 QSOP chips that I've been wanting to make into a DC/DC stepup converter but they're so small I've never known what to do with them.

I looked at the web site above and I still don't get it. Here's some questions:

1. How much have I got to spend to mount a couple of chips?

2. What do I mount them too? How does it keep the connections separate?

3. What kind of goop do I need to buy?

Sounds like I buy a tube of goop, put it on the chip, put the chip on the board in approximate position, heat it up, then by magic it all sticks to just the right place.

Please write more. This is very interesting.

 

[jeff1500]

http://www.seattlerobotics.org/encoder/200006/oven_art.htm

This is amazing. Here's a photo filled explanation.

 

[**DONOTDELETE**]

The process is definitely amazing.

See http://info.digikey.com/T013/V5/708.pdf and look under Solder Paste for details.

The stuff's expensive ($42.38 for a 35-gram syringe) but it must be fun to use.

 

[jeff1500]

http://shop.store.yahoo.com/tmt/solkessn.html

How about this stuff for $12.95 ???

 

[LED-FX]

Jeff thankyou very much for the additional info and finding a possible source of solder paste at a affordable price.

Thanks Again
Adam