Through Hole vs. Surface Mount

No need to switch to decaf. Just don't clench the iron; let the tip stay put, and if your hand wiggles, the iron wiggles in your hand and the tip stays put heating the pad. I avoided SMT for years, and then found that it was trivial to hand solder the stuff when I had to do some.

Surface mount is do-able. A good place to start is looking at the tutorials over at

As far as the holes go, you may want to at least try using 1/32" stock instead of 1/16" for your homebrew projects. Much easier to cut (heavy scissors will work) and drill. There is some loss of strength and stiffness, though, so it's not an all-purpose solution.

Is there a reason you don't want to go to one of the cheap Chinese or Bulgarian PCB makers? It will be much quicker than going the decaf route and for three boards not so expensive.

I second the SMT try. It's not as difficult as it seems. Get a good magnifier , headband type. A good pair of tweezers, fine tips for your iron, and fine 0.015" solder helps too.

There are some good parts out there that only come in SMT.

Cheers

A glass of Guinness works much better :-)

I like 0.015" Kester No-Clean best. No mess.

Yep, like tons of great RF transistors or fast opamps.

Go with surface mount. Standard SO packages and 1206/0805 passives are trivial to solder by hand, even by the inexperienced.

Dave.

Surface mount is pretty easy down to 0603, anyway. Some IC packages are a PITA, but most can be done with some practice (some even do BGA, but I wouldn't bother even trying). Forget RoHS and use real 63/37 lead/tin solder.

I've got a school project which, like most of my stuff, is through hole, but I cheaped out on gate drivers and went with complementary MOSFETs instead. They only come in SO-8, of course:

Tim

It boils down to what your time (and caffine buzz) are worth to you. :) If it were me and I just wanted to knock these out, I would order thru- hole boards (PCBExpress, ExpressPCS, PCB123, etc...). And just solder them up.

-mpm

I've found out recently that even my bifocal needing eyes can do 0603 parts relatively easily with a sharp pair of tweezers, a fine iron and a stereo microscope; qfp and soic packages are not that difficult either. In our office we routinely do 0402 resistors in low quantities with the same setup above.

re a

solder.

Yea, I think I might bite the bullet and try SMT. I have had to do some minor soldering in SM before. Do you guys recommend some type of adhesive to hold the part still while soldering?

Chris Maness

solder.

What I found/learned is to solder one pin first, solder the second and retouch both, ie. I put a small piece of solder on one pad (regardless of how many pins the device has), align the part with a tweezer on the board and apply the iron while holding the part in place. This makes a small connection which holds the part in place while you solder the other pin(s). Finally you revisit the first pin and retouch it with a little bit more solder. A hot, fine tip iron and thin solder are essential.

No. The standard technique is to tin one pad first, then with finew tweezers hold the part in place while you heat up the pad. Then simply solder the other end of the part. Some like to do just one side of all parts first and then go back and do the other ends in one hit.

IC's are similar, tin one pad, solder IC in place, soler an opposite pin, and then solder everything else.

Use a small chisel point point, not a round conical one. And use 0.56mm or finer solder if you can get it.

Dave.

About 3 maybe 4 years ago I had to be pep-talked into "hand-soldering" SMT components for prototype development purposes.

Strangely enough, the one to pep-talk me into this described means and comfort level only good down to 1206 ("3216 metric") size.

Thankfully, I was as always and still am an adventurous and experimental type, and the "pep-talk" pep-talked me into trying "being my own dog" for hand-soldering "0603 size" ("1608 metric") componments onto boards of my design.

Turns out, I succeeded. I have my own favored technique (even if it is a Don Klipstein Jr nutcase-bicycle-messenger-sort-of-technique):

I peel containing-outer-tape-layer from cut-tape to dispense components onto my workbench.

Next, I paint rubber cement onto the edge of my left index fingernail. (I am right-handed 40% ambidextrous).

To stick a component onto my fingernail edge to transport the compionent onto the board, first step of that has been for me to "land" my fingertip onto the workbench surface into a position where my freshly-gluey fingernail can be lowered onto the component.

Next, I make my left index finger more vertical, so as to "land" my "freshly-gluey" fingernail edge onto the component.

That usually gets followed by myself successfully transporting the component in question to a millimeter or two above where it has to be soldered into.

The next step is for me to "rotate" that finger of mine or tip thereof into a more vertical position, to push the component onto the board where it belongs.

If that does not work out so well, then I back up a bit and repeat, sometimes yelling 4-letter words or "And the horse you rode in on".

When I get the component successfully or "reasonably successfully" "placed", by that time my right hand is holding a soldering iron or is about to do so.

At that point, I use the soldering iron to tack one end or lead of the component in question onto the board.

Following that, I use thin rosin core solder wire and the iron to "properly hand solder" all connections fromthe board to the component in question, with the one that I quickie-earlier did being last.

- Don Klipstein ( snipped-for-privacy@misty.com)

Soldering fine pitch devices is like anything else, once you do it, your done.

Its not as hard as you think it is.

I would like to know, after all these years, why are fine pitch device still so scary ??

Yes, BGA and QFN device are tougher, but QFP are easy once you do it a few times.

Any ideas ?

hamilton

Tim Williams a écrit :

You definitely need to improve your process (or switch to one of the cheap PCB makers)

SMD is a lot less difficult than it looks. The space savings and the option to mount components on both sides of the board are a nice bonus in addition to the drilling.

ood

er

, but

ad.

I agree! I personally don't understand why ANYONE would want to make their own circuit boards. There must be some level of satisfaction in rolling your own, but not for me. One mis-step, and you've potentially ruined hours worth of work, only to start all over again. Plus, after you're purchased the bare copper boards, the checmials, the drills, and include your time -- it costs way more than the cheap PCB houses. With the latter giving you near perfect boards most of the time, on 2 or 3 day turns, for $50 or so, and some even include the silkscreening.

To me, it's a no-brainer. SMT or thru-hole.

-mpm

Robert Baer wrote in news:xLqdnSAtgJGa0S3WnZ2dnUVZ snipped-for-privacy@posted.localnet:

making a one-off PCB to use fine pitch ICs is the real problem.

I have a project on hold until I can figure out how to make a PCB for a 8 pin eMSOP package,LM3410XMY. the entire IC is about the size of a pencil eraser. :-(

(It's a boost LED driver-regulator,1 IC and 7 other parts,all 0603 size)