# Surface Mount Assembly Training courses - worth taking?

N

#### [email protected]

Jan 1, 1970
0
Hello. I'm new to electronics and I was wondering if taking some
training in surface mount assembly techniques is something worth
doing.

There is a local college that offers a surface mount assembly course
that costs about $300 for 21 hours of instruction. There are also some online video courses for$99. I've also seen a few
interactive CDs for $185 or DVD video courses for about$99.

What is everyone's opinion about those options? Are there any books
I can buy that are just as effective as a training course?

Also, what surface mount equipment would you recommend that I
get? I'll like to buy some inexpensive equipment while I'm learning
how to build some simple surface mount component based kits.

H

#### happyhobit

Jan 1, 1970
0
If your goal is to get a job, YES. If it's to learn something, NO.

There's not much you can't find in the internet. The "How To's" of SMT and
+ SMD + tools + techniques (I got 1090 matches). You can buy kits of junk
Surface Mount Devices to practice on.

If you have an extra $300 go for it, otherwise teach yourself. I taught myself mictocomputers 25 years ago. All formal education provides is a certificate that may impress a boss who doesn't know how to do it. "Nothing worth learning can be taught", Oscar Wilde Jay N #### [email protected] Jan 1, 1970 0 If your goal is to get a job, YES. If it's to learn something, NO. There's not much you can't find in the internet. The "How To's" of SMT and SMD are everywhere. "Google is your Friend" Do a Google search for, SMT + SMD + tools + techniques (I got 1090 matches). You can buy kits of junk Surface Mount Devices to practice on. If you have an extra$300 go for it, otherwise teach yourself. I taught
myself mictocomputers 25 years ago.

All formal education provides is a certificate that may impress a boss who
doesn't know how to do it.

I've spoken to a couple of technicians and engineers who were SMT
self taught.

There are several online courses and books on SMT assembly, the
cost is about $100. Do you think buying a$50 or $100 book is worth it? Are there a few important details about SMT assembly that you need to know that a book can list? N #### [email protected] Jan 1, 1970 0 If your goal is to get a job, YES. If it's to learn something, NO. There's not much you can't find in the internet. The "How To's" of SMT and SMD are everywhere. "Google is your Friend" Do a Google search for, SMT + SMD + tools + techniques (I got 1090 matches). You can buy kits of junk Surface Mount Devices to practice on. Hi, it's me, the Newbie, again. Thanks for the google search string, I used it and several good links popped up. I guess this is an example of how knowing about a topic can be enormously helpful in finding out even more about that topic. Not knowing much about SMT, I had used variants of "surface mount assembly" as a search string and while there were many hits, they were mostly oriented towards SMT assembly courses. The string you suggested resulted in web pages meant to teach hobbyists the ways of SMT assembly, just what I was looking for. If you have an extra$300 go for it, otherwise teach yourself. I taught
myself mictocomputers 25 years ago.

It looks like we're both old timers. ;->

A very long time ago a friend and I built an S-100 memory board from
a kit. It was a 32K SD Sales Expandorram. I think it cost $400 and the machine is still in my basement. H #### happyhobit Jan 1, 1970 0 My first computer was a Netronics ELF 2 I built back in 1978. I don't remember what it cost, something ridiculous I'm sure. It came with 256 Bytes of memory and I added a 4k memory board, 32 1k by 1 chips. I do remember that my first floppy drive cost$300. Single density (360K)
double sided. I patched the OS of an 'Ohio Scientific' so I could access the
two sides by pressing 'Ctrl'1 or 'Ctrl'2.

Ah, the good old days. Still got them in my basement.

I recently started playing with AVR microcontrollers, 128 bytes Eprom, 128
bytes SRAM, 2k of flash memory for $3.50. Ah, the good new days. Jay .. N #### [email protected] Jan 1, 1970 0 My first computer was a Netronics ELF 2 I built back in 1978. I don't remember what it cost, something ridiculous I'm sure. It came with 256 Bytes of memory and I added a 4k memory board, 32 1k by 1 chips. I do remember that my first floppy drive cost$300. Single density (360K)
double sided. I patched the OS of an 'Ohio Scientific' so I could access the
two sides by pressing 'Ctrl'1 or 'Ctrl'2.

Ah, the good old days. Still got them in my basement.

I recently started playing with AVR microcontrollers, 128 bytes Eprom, 128
bytes SRAM, 2k of flash memory for $3.50. Ah, the good new days. Jay I've been looking at the TI MSP430 series of micocontrollers, which is what led me to investigate SMT assembly. The funny part is that the largest MSP model runs at 6Mhz, has something like 48K of flash and 10K of sram for about$6. The first Z80 machine I bought ran at 2Mhz,
started out with 32K of ram and had a 90K floppy (the old Northstar
hard sector drive) and cost thousands of dollars. You're right, these
are the good old days.

BTW, are there any books on SMT techniques that would be useful or
would learning from a web page be sufficient? I've found a lot of web
pages that describe SMT assembly, is there anything about SMT that a
book would cover that a web page like the ones below might miss?

http://www.norcalqrp.com/smt/vk33msmt.htm

http://www.twyman.org.uk/PCB-Techniques/index-frame.htm

H

#### happyhobit

Jan 1, 1970
0
Well I'm a hands on kind of guy.

I knew a guy back in the early 80's who was going to buy the latest and
greatest computer as soon as it came out. Every time I saw him he would talk
about another computer he heard of that he was going to buy as soon as it
came out.

I bought 3 books. One on 8080 assembly, one on 6502 assembly and one on 6800
assembly. (There was no Internet back then) Then I built this computer and
bought that computer, soldered kits, built wire-wrap boards, wrote programs
in 1802 assembly, 6502 assembly, basic, forth, disassembled operating
systems, made a lot of mistakes and learned a LOT.

I don't know if that guy ever bought a computer, probably not, but I
parlayed a lot of tinkering and a Journeyman's card into a career in
electronics and had a lot of fun along the way.

Personally I'd get;
A loupe and a table mounted lamp / magnifying glass.
Some de-soldering braid,
A Solder Sucker,
A Small soldering Iron, 30 Watt with a 1/16 tip,
A flux pen (a felt tip pen with flux.),
A SMT soldering kit http://www.cpcares.com/ESM200K.html for $22 ( I'm Cheep) ( Or one of the$60 to $100 "SMT soldering kits" if you're not.) And melt some solder I looked it the sites you posted and they provide the basics. After that it' s a mater of practice, hands on. Of course that's just my opinion and everybody has one. Jay P.S. I don't know what applications you have in mind for a microcontrollers, but take a look at AVR. N #### [email protected] Jan 1, 1970 0 Well I'm a hands on kind of guy. I knew a guy back in the early 80's who was going to buy the latest and greatest computer as soon as it came out. Every time I saw him he would talk about another computer he heard of that he was going to buy as soon as it came out. I bought 3 books. One on 8080 assembly, one on 6502 assembly and one on 6800 assembly. (There was no Internet back then) Then I built this computer and bought that computer, soldered kits, built wire-wrap boards, wrote programs in 1802 assembly, 6502 assembly, basic, forth, disassembled operating systems, made a lot of mistakes and learned a LOT. I don't know if that guy ever bought a computer, probably not, but I parlayed a lot of tinkering and a Journeyman's card into a career in electronics and had a lot of fun along the way. Personally I'd get; A loupe and a table mounted lamp / magnifying glass. Some de-soldering braid, A Solder Sucker, A Small soldering Iron, 30 Watt with a 1/16 tip, A flux pen (a felt tip pen with flux.), A SMT soldering kit http://www.cpcares.com/ESM200K.html for$22 ( I'm Cheep)
( Or one of the $60 to$100 "SMT soldering kits" if you're not.)

And melt some solder

I looked it the sites you posted and they provide the basics. After that it'
s a mater of practice, hands on. Of course that's just my opinion and
everybody has one.

Thanks for checking over those web pages, it's good to know that
someone experienced thinks those pages are on the right track. Over
the past few days I've been reading those web pages, along with
dozens of other threads and web pages on SMD assembly and test
equipment.

One web page suggested getting the kind of magnifying eyeglasses that
watchmakers or jewelers use but I may go with one of those third hand
clamps with a built in and position adjustable magnifying glass. I saw
one at a surplus electronics store today for 5. It was a little light on construction and the magnifying glass only had a plastic lens so I think I'll try to find a better one. I've found a few interesting newsgroup threads about SMD assembly, which I've pasted to the end of this post. I think I'll see if I can find the "hoof" tip mentioned in the threads. ........................ What you need is FLUX - I solder these kind of things with a moderate sized iron, regular (0.028) solder, and flux. Get a corner pin located, tack solder, locate other corner, tack solder (just put a little solder on the tip of you iron) -flux the pins on a side you didn't tack, and then drag the tip and solder along, repeat, and clean with flux remover -I learned this from a lady who did commercial rework on SMD's for a lving - I've put 0.5mm parts on with not problem pretty quick. Now a 201 resitor or cap is another story - I'm a tombstoner. Anyone know how to do these things well? .............. Andrew, I totally agree with what you've said below. I used to do i486 and Pentium mainboard rework by the palet before and this is exactly what we do from 8 pin SOIC to 208 pin QFPs. Flux, right heat, medium soldering iron tip (small one don't deliver that much heat) and 63/37 solder will do the job. The result is almost like that of the production ones after cleaning up the excess flux. As for the braid, I use it for stubborn solder bridges and I don't recommend the shotgun approach of filling everything with solder then clean up with the braid as what some has suggested. You'll end up with misaligned pins and damaged ugly board. For SMT resistors and caps, if you have two irons then just put one tip on each end and lift or you can buy those fancy tips. PJ .......... You'll find there are several techniques. From trial & error (and later a little advice from a rework tech at Intel), here's mine for working with 0.5mm pitch, 128-pin SMDs: * Flux the pads * Position the piece * *Very light* downward pressure to prevent shifting * Place a small bit of solder on the iron tip * Tack one corner pin * Ensure device is positioned properly * Tack opposite corner * Flux the pins * Place a small amount of solder on the iron * Stroke each pin away from the body toward the tip - Flux will help the solder wick around/under the pin - The stroke guides solder balls to the tip of the foot - You can do several pins at once if the tip is wide * Cleanup with solder braid Some key tricks: - I didn't have good success with the "blob it on, run to the end of the row" technique at lower temperatures. The pin-by-pin technique is a little more tedious, but more consistent with fine-pitch devices. - *Don't* use a very fine tip. I started with a narrow-tip 1/32" "screwdriver" tip, but discovered that it had problems transferring enough heat on larger packages. A conical 1/32" screwdriver tip worked much better, as did a common 1/8" conical screwdriver tip. - Good tinning on the tip is key, since you want the solder to flow off smoothly, not ball up and come off in globs. If you do many, you may find yourself replacing the tip regularly. There are good tricks to prolonging the life of the tip's tinning - search google for 'soldering iron tip tinning'. Basically, cover the tip in solder when it's idle in the stand to prevent oxidation; wipe it off before you start a joint, not after. - You don't need thin-gauge solder, since you're applying it to the tip, not the pad. Some folks prefer paste solder, but I've had better success with wire solder. - Use a flux pen, like MG Chemicals' (Fry's Electronics). It goes on thin, applies easily, makes less mess. - Flux is your best friend here. You're bound to get bridges or solder globs behind pins. They can be coaxed out with flux, an outward stroking motion, and braid to remove excess. - Rather than using a stereo microscope, I use a jeweller's magnifying visor in the strongest strength to do the soldering, with a jeweller's loupe for inspection. Micromark.com sells both, and the loupe attaches to the visor. - Bright lighting is good. I use a small 20W halogen desk lamp on an arm to position it close to the work and move it around to minimize shadows on the pin edges. - Use a temp controlled iron, set to ~220 C. Check the specs on your parts for maximum soldering temperature and time tolerances. - If you'd like some practice, check out the dummy parts at http://www.practicalcomponents.com and practice first on a spare PCB. They supply exact mechanical parts for about1 each - worthwhile if
your live parts are $10-$30.
......................
Metcal makes a "hoof tip" just for this. It looks like a medium-small
conical tip that has a flat on one side. When you put solder on it, a
nice juicy blob parks on the flat, and as you run the pointy tip down
the row of fluxed pins, the solder slurps off onto each pin in just
the right amount. My people solder 240-pin FPGAs in just a minute or
two this way.

If anybody is doing any serious amount of soldering/desoldering,
Metcal gear is well worth it.

John
................
I'm using this thing (its equivalent from Weller) to solder 100 pin
FPGAs
and it does work. But you need flux to prevent solder from spilling
over
multiple pins and shorting them together. I also found that this works
better
with higher temperature, I do it at around 400C.

Soldered in about 600 over the years this way.

Siol
...............
Do you happen to have the tip number handy? I'm using a conical tip
with a flat grind on it ("screwdriver" tip), but I haven't seen a hoof
tip from Weller like John describes.

Oh, one other tip: Metcal makes two hoofers, big and small, and my
people prefer the big one. It holds more solder and works great on the
fine-pitch parts.

All this stuff is counter-intuitive.
...............

Ever heard of rework paste? just clean up the pads and tin them paint
on
the rework paste then place the component on the pads, you can then
either
do every pin with your iron or use a hot air pen to fix the device
afterwards clean up with some isoprop and a brush, Ive fitted loads od
chips
with this method and I might say with pin spacings of much less that
1mm
,,,,,,, good luck
..........

N

#### [email protected]

Jan 1, 1970
0

Thanks again. I finally got around to checking out the AVR line from
Atmel. When we last looked at the AVR line over a year ago, the TI MSP
product lineup was much broader, cheaper and used less power. Our main
requirement was extremely low power consumption and the app had to be
very low cost, so the MSP won out.

However, I see that Atmel has added a number of parts at both the low
end and high end. I'll have to get the AVR datasheets and do a more
detailed comparison and see how the new parts fit our app.

From a quick check, it looks like the AVR parts can run at higher
clock speeds but the MSP parts can have more peripherals on board. So
the choice isn't as clear cut as it was a year ago.

N

#### nobody

Jan 1, 1970
0

Thanks again. I finally got around to checking out the AVR line from
Atmel. When we last looked at the AVR line over a year ago, the TI MSP
product lineup was much broader, cheaper and used less power. Our main
requirement was extremely low power consumption and the app had to be
very low cost, so the MSP won out.

However, I see that Atmel has added a number of parts at both the low
end and high end. I'll have to get the AVR datasheets and do a more
detailed comparison and see how the new parts fit our app.

From a quick check, it looks like the AVR parts can run at higher
clock speeds but the MSP parts can have more peripherals on board. So
the choice isn't as clear cut as it was a year ago.

N

#### nobody

Jan 1, 1970
0
Personally I'd get;
A loupe and a table mounted lamp / magnifying glass.
Some de-soldering braid,
A Solder Sucker,
A Small soldering Iron, 30 Watt with a 1/16 tip,
A flux pen (a felt tip pen with flux.),
A SMT soldering kit http://www.cpcares.com/ESM200K.html for $22 ( I'm Cheep) ( Or one of the$60 to $100 "SMT soldering kits" if you're not.) And melt some solder I looked it the sites you posted and they provide the basics. After that it' s a mater of practice, hands on. Of course that's just my opinion and everybody has one. Thanks for checking over those web pages, it's good to know that someone experienced thinks those pages are on the right track. Over the past few days I've been reading those web pages, along with dozens of other threads and web pages on SMD assembly and test equipment. One web page suggested getting the kind of magnifying eyeglasses that watchmakers or jewelers use but I may go with one of those third hand clamps with a built in and position adjustable magnifying glass. I saw one at a surplus electronics store today for$5. It was a little light
on construction and the magnifying glass only had a plastic lens so I
think I'll try to find a better one.

which I've pasted to the end of this post. I think I'll see if I can
find the "hoof" tip mentioned in the threads.

........................

What you need is FLUX - I solder these kind of things with a moderate
sized iron, regular (0.028) solder, and flux.

Get a corner pin located, tack solder, locate other corner, tack
solder
(just put a little solder on the tip of you iron) -flux the pins on a
side you didn't tack, and then drag the tip and solder along, repeat,
and clean with flux remover -I learned this from a lady who did
commercial rework on SMD's for a lving - I've put 0.5mm parts on with
not problem pretty quick. Now a 201 resitor or cap is another story -
I'm a tombstoner. Anyone know how to do these things well?

..............
Andrew,

I totally agree with what you've said below. I used to do i486 and
Pentium mainboard rework by the palet before and this is exactly what
we
do from 8 pin SOIC to 208 pin QFPs. Flux, right heat, medium soldering
iron tip (small one don't deliver that much heat) and 63/37 solder
will
do the job. The result is almost like that of the production ones
after
cleaning up the excess flux.

As for the braid, I use it for stubborn solder bridges and I don't
recommend the shotgun approach of filling everything with solder then
clean up with the braid as what some has suggested. You'll end up with
misaligned pins and damaged ugly board.

For SMT resistors and caps, if you have two irons then just put one
tip
on each end and lift or you can buy those fancy tips.

PJ
..........

You'll find there are several techniques. From trial & error (and
later
a little advice from a rework tech at Intel), here's mine for working
with 0.5mm pitch, 128-pin SMDs:

* Position the piece
* *Very light* downward pressure to prevent shifting
* Place a small bit of solder on the iron tip
* Tack one corner pin
* Ensure device is positioned properly
* Tack opposite corner

* Flux the pins
* Place a small amount of solder on the iron
* Stroke each pin away from the body toward the tip
- Flux will help the solder wick around/under the pin
- The stroke guides solder balls to the tip of the foot
- You can do several pins at once if the tip is wide
* Cleanup with solder braid

Some key tricks:

- I didn't have good success with the "blob it on, run to the end of
the
row" technique at lower temperatures. The pin-by-pin technique is a
little more tedious, but more consistent with fine-pitch devices.

- *Don't* use a very fine tip. I started with a narrow-tip 1/32"
"screwdriver" tip, but discovered that it had problems transferring
enough heat on larger packages. A conical 1/32" screwdriver tip
worked
much better, as did a common 1/8" conical screwdriver tip.

- Good tinning on the tip is key, since you want the solder to flow
off
smoothly, not ball up and come off in globs. If you do many, you may
find yourself replacing the tip regularly. There are good tricks to
prolonging the life of the tip's tinning - search google for
'soldering
iron tip tinning'. Basically, cover the tip in solder when it's idle
in
the stand to prevent oxidation; wipe it off before you start a joint,
not after.

- You don't need thin-gauge solder, since you're applying it to the
tip,
not the pad. Some folks prefer paste solder, but I've had better
success with wire solder.

- Use a flux pen, like MG Chemicals' (Fry's Electronics). It goes on
thin, applies easily, makes less mess.

- Flux is your best friend here. You're bound to get bridges or
solder
globs behind pins. They can be coaxed out with flux, an outward
stroking motion, and braid to remove excess.

- Rather than using a stereo microscope, I use a jeweller's magnifying
visor in the strongest strength to do the soldering, with a jeweller's
loupe for inspection. Micromark.com sells both, and the loupe
attaches
to the visor.

- Bright lighting is good. I use a small 20W halogen desk lamp on an
arm to position it close to the work and move it around to minimize

- Use a temp controlled iron, set to ~220 C. Check the specs on your
parts for maximum soldering temperature and time tolerances.

- If you'd like some practice, check out the dummy parts at
http://www.practicalcomponents.com and practice first on a spare PCB.
They supply exact mechanical parts for about $1 each - worthwhile if your live parts are$10-\$30.
......................
Metcal makes a "hoof tip" just for this. It looks like a medium-small
conical tip that has a flat on one side. When you put solder on it, a
nice juicy blob parks on the flat, and as you run the pointy tip down
the row of fluxed pins, the solder slurps off onto each pin in just
the right amount. My people solder 240-pin FPGAs in just a minute or
two this way.

If anybody is doing any serious amount of soldering/desoldering,
Metcal gear is well worth it.

John
................
I'm using this thing (its equivalent from Weller) to solder 100 pin
FPGAs
and it does work. But you need flux to prevent solder from spilling
over
multiple pins and shorting them together. I also found that this works
better
with higher temperature, I do it at around 400C.

Soldered in about 600 over the years this way.

Siol
...............
Do you happen to have the tip number handy? I'm using a conical tip
with a flat grind on it ("screwdriver" tip), but I haven't seen a hoof
tip from Weller like John describes.

Oh, one other tip: Metcal makes two hoofers, big and small, and my
people prefer the big one. It holds more solder and works great on the
fine-pitch parts.

All this stuff is counter-intuitive.
...............

Ever heard of rework paste? just clean up the pads and tin them paint
on
the rework paste then place the component on the pads, you can then
either
do every pin with your iron or use a hot air pen to fix the device
afterwards clean up with some isoprop and a brush, Ive fitted loads od
chips
with this method and I might say with pin spacings of much less that
1mm
,,,,,,, good luck
..........

H

#### happyhobit

Jan 1, 1970
0
The loupe is for inspecting the board after you solder it. (The old type
looked like a black shot glass that was shoved in the eye socket, my loupe
clips on to the sidepiece of my glasses.) With a focal length of 2", it's a
little close to work with. (Kept burning my nose hairs.) A table mounted
lamp / magnifying glass is the best for working. ( a fixed magnifying glass
with extra good lighting works, or as someone suggested a jeweler's
magnifying visor, with good lighting.)

I use a 33 watt Ungar with a PL-114 (Micro Spade tip). I think this would
constitute a "hoof" tip

http://www.action-electronics.com/unpl.htm#On

I also use a sharpened 3/16 dowel rod (sharpened in pencil grinder) to hold
the chip in position while tacking it down.

Rework paste (soldering paste) a fine ground solder mixed with flux, some
like it, some don't, it's expensive, ages poorly. (keep refrigerated but not
with food) I've used it, it is good, I don't need it.

You've got lots of opinions from the newsgroup threads. Pick and chose until
you find what works good for you, some will, some won't, we're all
different.

Jay

Replies
16
Views
908
Replies
15
Views
2K
Replies
3
Views
2K
Replies
1
Views
2K
Replies
2
Views
557