It's official - I *hate* surface-mount junk. Too small
for human beings. I'm forever bridging connections or
overheating or underheating or going blind from the
magnifier or ... well ... you know. SMT is for ROBOTS.

I can't be alone.

So ... somebody, SOMEWHERE, must make adaptor modules
that provide good SOCKETS for the various kinds of
SMT chips and send the leads to good old 0.10 DIP
style pins on the bottom side. Solder the 0.10 pins
into your board, press in the SOIC or whatever chip
into the socket above.

Yes, I'd gladly PAY for such things ... more than a
dollar too.

Aries,MillMax and a few others ALMOST sell what I'm
looking for - except that you still have to solder
the SMT device to the provided pseudo-DIP chip. Almost
as bad as having to solder SMT directly to the board.

Sockets are the answer.

But WHERE can such things be had ?

ANY info greatly appreciated !

On Jan 10, 8:02 am, b...@barrk.net (B1ackwater) wrote:
> It's official - I *hate* surface-mount junk. Too small
> for human beings. I'm forever bridging connections or
> overheating or underheating or going blind from the
> magnifier or ... well ... you know. SMT is for ROBOTS.
>
> I can't be alone.
>
> So ... somebody, SOMEWHERE, must make adaptor modules
> that provide good SOCKETS for the various kinds of
> SMT chips and send the leads to good old 0.10 DIP
> style pins on the bottom side. Solder the 0.10 pins
> into your board, press in the SOIC or whatever chip
> into the socket above.
>
> Yes, I'd gladly PAY for such things ... more than a
> dollar too.
>
> Aries,MillMax and a few others ALMOST sell what I'm
> looking for - except that you still have to solder
> the SMT device to the provided pseudo-DIP chip. Almost
> as bad as having to solder SMT directly to the board.
>
> Sockets are the answer.
>
> But WHERE can such things be had ?
>
> ANY info greatly appreciated !

Which prototype chip/board do you want?

"B1ackwater" <bw@barrk.net> wrote in message
news:47864166.18347203@news.east.earthlink.net...
> I'm forever bridging connections or
> overheating or underheating or going blind from the
> magnifier or ... well ... you know.

Flux is your friend, as are decent (temperature-controlled) soldering irons.
(E.g., the orange-base Wellers are kinda junky, the blue-based ones are
good... or you can get a used Metcal for not much more than the price of a new
Weller.)

> So ... somebody, SOMEWHERE, must make adaptor modules
> that provide good SOCKETS for the various kinds of
> SMT chips and send the leads to good old 0.10 DIP
> style pins on the bottom side.

There are sockets for SMT chips, but they're quite expensive (almost always
exceeding the price of the chip itself); I think that's why you don't see too
many. I have seen some such adapters for large BGA parts where they figure
you're using, e.g., a $600 FPGA so a $500 adapter is probably not a big
deal...

---Joel

Also... not exactly what you asked for, but these might make it a little
easier: http://www.schmartboard.com/

B1ackwater wrote:
> It's official - I *hate* surface-mount junk. Too small
> for human beings. I'm forever bridging connections or
> overheating or underheating or going blind from the
> magnifier or ... well ... you know. SMT is for ROBOTS.
>
> I can't be alone.
>
> So ... somebody, SOMEWHERE, must make adaptor modules
> that provide good SOCKETS for the various kinds of
> SMT chips and send the leads to good old 0.10 DIP
> style pins on the bottom side. Solder the 0.10 pins
> into your board, press in the SOIC or whatever chip
> into the socket above.
>
> Yes, I'd gladly PAY for such things ... more than a
> dollar too.
>
> Aries,MillMax and a few others ALMOST sell what I'm
> looking for - except that you still have to solder
> the SMT device to the provided pseudo-DIP chip. Almost
> as bad as having to solder SMT directly to the board.
>
> Sockets are the answer.
>
> But WHERE can such things be had ?
>
> ANY info greatly appreciated !

The ones that I am familiar with are intended as adapters
for device programmers or prototyping. Very handy but
relatively expensive (and large).

Some examples at
http://www.logicalsys.com/
http://www.adapt-plus.com/products/adapters/index.html

--
Rich Webb Norfolk, VA

You used to be able to get them but lead pitches are so fine these days that
it's hard to make a socket for some.

Try..
http://qfp-adapter.com
Example photo..
http://aprilog.com/sites/qfp-adapter.co ... ZL-S-L.jpg

Expect $100 for some types.

On Thu, 10 Jan 2008 16:02:52 GMT, bw@barrk.net (B1ackwater) wrote:

>It's official - I *hate* surface-mount junk. Too small
>for human beings. I'm forever bridging connections or
>overheating or underheating or going blind from the
>magnifier or ... well ... you know. SMT is for ROBOTS.
>
>I can't be alone.

That's the way the world is going. It's great for board density, and
for speed, and for semi- or fully-automated assembly.

I was just prototyping some smt stuff. An 0805, or an SO-8, looks huge
to me now. I used to be intimidated by a 1206.

>
>So ... somebody, SOMEWHERE, must make adaptor modules
>that provide good SOCKETS for the various kinds of
>SMT chips and send the leads to good old 0.10 DIP
>style pins on the bottom side. Solder the 0.10 pins
>into your board, press in the SOIC or whatever chip
>into the socket above.
>
>Yes, I'd gladly PAY for such things ... more than a
>dollar too.

Clamshell sockets for surface-mount parts are huge and *very*
expensive... hundreds of dollars each. And most of them are... wait
for it... surface mount!


>
>Aries,MillMax and a few others ALMOST sell what I'm
>looking for - except that you still have to solder
>the SMT device to the provided pseudo-DIP chip. Almost
>as bad as having to solder SMT directly to the board.
>
>Sockets are the answer.

Too expensive.

The Beldyn adapters are nice:

ftp://66.117.156.8/NE3509M04.JPG

Don't give up. Get a good soldering iron and some good lighting and
magnifiers, and some tweezers and such, and relax and practice. It's
not that bad. Some people gave up electronics when transistors were
invented.

John

On Thu, 10 Jan 2008 16:02:52 +0000, B1ackwater wrote:

> It's official - I *hate* surface-mount junk. Too small
> for human beings. I'm forever bridging connections or
> overheating or underheating or going blind from the
> magnifier or ... well ... you know. SMT is for ROBOTS.
>
> I can't be alone.
....
> Sockets are the answer.

Why not make one? Take a plated board, etch the lead pattern on it. Then
take a piece of unplated board and cut a precise hole that confines the
chip's leads such that each lead lines up with a trace; then make another
part that clamps down over that, pressing the leads against the traces. If
the hole in the upper board is the right size, then you could just drop
the chip in and it would get aligned by the edges of the hole in the upper
board.

Of course, this will take some time - if you're being paid by the hour,
it'd be cheaper to hire some undergrad to just solder the chip in for you.

Good Luck!
Rich

On Thu, 10 Jan 2008 12:14:48 -0800, John Larkin
<jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

>
>Too expensive.
>
>The Beldyn adapters are nice:
>
>ftp://66.117.156.8/NE3509M04.JPG
>
>Don't give up. Get a good soldering iron and some good lighting and
>magnifiers, and some tweezers and such, and relax and practice. It's
>not that bad. Some people gave up electronics when transistors were
>invented.
>
>John

I'm in the same boat. Just don't think 37 gauge wire is real these
days. Back in my youth . . . that was the size of continents. (Now I
understand my dad - building that first induction coil he couldn't see
the 30 gauge)

I need a very fine gauge iron and can make connections with a
magnifying glass - not too much problem there. Brace my hand on lead
weight etc..

The problem I have is trying to get the sm stuff on a real BREADboard
that I can see with unaided vision. How does one get from the little
bity parts to real (24 gauge) wires on a real breadboard with 0.100
spacing?

I do have a somewhat solution - line a bunch of wires into a homemade
jig, apply hot melt glue to the wires and I have a sort of connector
(and they only work once or find themselves wall art) assuming the
reflow soldering works and I don't break a wire.

Reflow - some plumber's joint tape and a soldering iron.
--

On Thu, 10 Jan 2008 21:51:29 GMT, Rich Grise <rich@example.net> wrote:

>On Thu, 10 Jan 2008 16:02:52 +0000, B1ackwater wrote:
>
>> It's official - I *hate* surface-mount junk. Too small
>> for human beings. I'm forever bridging connections or
>> overheating or underheating or going blind from the
>> magnifier or ... well ... you know. SMT is for ROBOTS.
>>
>> I can't be alone.
>...
>> Sockets are the answer.
>
>Why not make one? Take a plated board, etch the lead pattern on it. Then
>take a piece of unplated board and cut a precise hole that confines the
>chip's leads such that each lead lines up with a trace; then make another
>part that clamps down over that, pressing the leads against the traces. If
>the hole in the upper board is the right size, then you could just drop
>the chip in and it would get aligned by the edges of the hole in the upper
>board.
>
>Of course, this will take some time - if you're being paid by the hour,
>it'd be cheaper to hire some undergrad to just solder the chip in for you.
>
>Good Luck!
>Rich
>
Traces? How about bread boarding? How to get the surface mount to
work with "real parts" (those visible to the naked eye with 20/20
vision)
--

default <default@defaulter.net> writes:
> The problem I have is trying to get the sm stuff on a real BREADboard

For SMT parts that I need to use on a breadboard, I usually etch a
small PCB to hold them. I reflow the parts onto the pcb, then solder
in the wire "pins". You can see a sample here:

http://www.delorie.com/electronics/alar ... kxtal.html

On 2008-01-10, B1ackwater <bw@barrk.net> wrote:
> It's official - I *hate* surface-mount junk. Too small
> for human beings.

Maybe *I'm* weird, but I prefer surface mount. I just made a board
with almost 300 components and assembled it by hand. Besides some
connectors and RA mount stuff on the edge there's only one through-
hole component I can think of (LM34).

I hate building through-hole boards (mostly kits). If you stuff too
many parts the leads get crazy to trim, some parts always pop up from
the board while you're soldering them, the resulting board is unfriendly
to the fingers (not as bad as press fit!).

> overheating or underheating or going blind from the
> magnifier or ... well ... you know. SMT is for ROBOTS.

It does help to do some SMT work under a good stereo scope just to get
a feel for what's going on. You don't necessarily need to see it happen
every time.

> So ... somebody, SOMEWHERE, must make adaptor modules
> that provide good SOCKETS for the various kinds of
> SMT chips

The funny thing is that I think chips are easier to solder than discretes.
The smaller the resistor/cap, the more they want to stand up when you tack
one end. And it seems like the second end always has a tendancy to get
a bit blobby. With big chips you just use lots of flux and the solder
knows what to do. I've done several 0.5mm QFP (a few with no soldermask
due to my own mistake with the apertures) and never even had a shorted
pin. Bent them, yes (urrrgh)

> Yes, I'd gladly PAY for such things ... more than a
> dollar too.

More than a hundred dollars? I think that's what you're looking at.
Also, they're huge (tall and wide) because they include parts akin
to medieval torture devices to clamp the chip down. Seems to me some
of them are SMT, too.

--
Ben Jackson AD7GD
<ben@ben.com>
http://www.ben.com/

"B1ackwater" <bw@barrk.net> wrote in message
news:47864166.18347203@news.east.earthlink.net...
> It's official - I *hate* surface-mount junk. Too small
> for human beings. I'm forever bridging connections or
> overheating or underheating or going blind from the
> magnifier or ... well ... you know. SMT is for ROBOTS.
>
> I can't be alone.
>
> So ... somebody, SOMEWHERE, must make adaptor modules
> that provide good SOCKETS for the various kinds of
> SMT chips and send the leads to good old 0.10 DIP
> style pins on the bottom side. Solder the 0.10 pins
> into your board, press in the SOIC or whatever chip
> into the socket above.
>
> Yes, I'd gladly PAY for such things ... more than a
> dollar too.
>
> Aries,MillMax and a few others ALMOST sell what I'm
> looking for - except that you still have to solder
> the SMT device to the provided pseudo-DIP chip. Almost
> as bad as having to solder SMT directly to the board.
>
> Sockets are the answer.
>
> But WHERE can such things be had ?
>
> ANY info greatly appreciated !

As people say, they're expensive. But if you want to look:

Ex: http://www.arieselec.com/RF/ARIES_RF_Te ... s_Page.htm

Robert H.

John Larkin wrote:

> On Thu, 10 Jan 2008 16:02:52 GMT, bw@barrk.net (B1ackwater) wrote:
>
>
>>It's official - I *hate* surface-mount junk. Too small
>>for human beings. I'm forever bridging connections or
>>overheating or underheating or going blind from the
>>magnifier or ... well ... you know. SMT is for ROBOTS.
>>
>>I can't be alone.
>
>
> That's the way the world is going. It's great for board density, and
> for speed, and for semi- or fully-automated assembly.
>
> I was just prototyping some smt stuff. An 0805, or an SO-8, looks huge
> to me now. I used to be intimidated by a 1206.
>
>
>>So ... somebody, SOMEWHERE, must make adaptor modules
>>that provide good SOCKETS for the various kinds of
>>SMT chips and send the leads to good old 0.10 DIP
>>style pins on the bottom side. Solder the 0.10 pins
>>into your board, press in the SOIC or whatever chip
>>into the socket above.
>>
>>Yes, I'd gladly PAY for such things ... more than a
>>dollar too.
>
>
> Clamshell sockets for surface-mount parts are huge and *very*
> expensive... hundreds of dollars each. And most of them are... wait
> for it... surface mount!
>
>
>
>>Aries,MillMax and a few others ALMOST sell what I'm
>>looking for - except that you still have to solder
>>the SMT device to the provided pseudo-DIP chip. Almost
>>as bad as having to solder SMT directly to the board.
>>
>>Sockets are the answer.
>
>
> Too expensive.
>
> The Beldyn adapters are nice:
>
> ftp://66.117.156.8/NE3509M04.JPG
>
> Don't give up. Get a good soldering iron and some good lighting and
> magnifiers, and some tweezers and such, and relax and practice. It's
> not that bad. Some people gave up electronics when transistors were
> invented.
>
> John
>
I designed a similar board for SOT-23 and the like, with DIP-8 pins.
Used some high-temp board and they are rather useful.
Do not know how to sell it, so am stuck with thousands of those
press-mount pins...

B1ackwater wrote:
> It's official - I *hate* surface-mount junk. Too small
> for human beings. I'm forever bridging connections or
> overheating or underheating or going blind from the
> magnifier or ... well ... you know. SMT is for ROBOTS.
>
> I can't be alone.

I thought like that up until a year ago until I bit the bullet an sat down
and made my first SMD board. SO8/0805/SOT-23. I used a
temperature-controlled Weller with a fine tip, PbSnAg solder and
occasionally liquid flux to be applied with a fine brush. The board was made
in a board house and luckily gold-plated (they just throw the prototypes
into their batch pool, you never know what surface finish you get).

At first I was intimidated, but after a few parts I knew I would never want
to go back to TPH. Assembly is a lot faster than TPH because you don't need
to bend and clip leads.

Given the right tools even rework is much easier than on TPH. I got the
cheapest solering tweezers I could find, a rather clumsy Weller model that
plugs into their standard electronic temperature controllers. It takes five
seconds to remove a SO16 chip (but several minutes to fit and align the
proper tweezer tips and to heat up the iron

Try it, you'll love it. I've never tried this on homemade boards, but if you
do make sure to tin the pads really well before assembly. And use extra flux
if you reflow connections.

And practise. I ripped the controller board out of a dead hard drive, baked
it in the oven at 210 deg C for a while an then gave it a single, hard rap
onto the tabletop. 99% of components flew right off, yielding hours worth of
free practice components and a PCB. (even if you abhor SMD assembly, this is
fun BTW.)

There are people who say that 0.5mm pitch components are easy to solder by
hand. After trying it with the controller chip on said harddisk PCB I can't
conirm that, but the leads of the chip were slightly bent and unevenly
tinned. Maybe with a new chip and PCB it is easier.

Good luck!

robert

"Robert Baer" <robertbaer@localnet.com> wrote in message
news:13oedtpchlogj4a@corp.supernews.com...
> I designed a similar board for SOT-23 and the like, with
DIP-8 pins.
> Used some high-temp board and they are rather useful.
> Do not know how to sell it, so am stuck with thousands of
those
> press-mount pins...
>
are those the pins that you press onto the side of a standard PCB
(where there is a pad or trace contact) to give the PCB a DIP
like appendage/appearance ? and are they the solderable type ?

i have been searching to purchase some of those but can not find
a source that sells them in small lots (ie. 500) ? i have found
rolls (15-25 thousand) ....

if you are looking to rid yourself of some of that excess
inventory then do you sell on th-e-bay ?

robb

"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in message
news:cusco3ln1i8m6c15r2d08f37t91p5pp4ac@4ax.com...
> Don't give up. Get a good soldering iron and some good lighting and
> magnifiers, and some tweezers and such, and relax and practice. It's
> not that bad. Some people gave up electronics when transistors were
> invented.
>
> John
>

I once had to ask a technician (Hi Terry) if he could remove a 160 pin TQFP
with hand tools and save both the board and the device. I can't recall the
lead pitch but it was hard to see the gaps between leads with the naked eye.
He said he would try and he managed it.

On Thu, 10 Jan 2008 13:10:57 -0500, Rich Webb
<bbew.ar@mapson.nozirev.ten> wrote:

>B1ackwater wrote:
>> It's official - I *hate* surface-mount junk. Too small
>> for human beings. I'm forever bridging connections or
>> overheating or underheating or going blind from the
>> magnifier or ... well ... you know. SMT is for ROBOTS.
>>
>> I can't be alone.
>>
>> So ... somebody, SOMEWHERE, must make adaptor modules
>> that provide good SOCKETS for the various kinds of
>> SMT chips and send the leads to good old 0.10 DIP
>> style pins on the bottom side. Solder the 0.10 pins
>> into your board, press in the SOIC or whatever chip
>> into the socket above.
>>
>> Yes, I'd gladly PAY for such things ... more than a
>> dollar too.
>>
>> Aries,MillMax and a few others ALMOST sell what I'm
>> looking for - except that you still have to solder
>> the SMT device to the provided pseudo-DIP chip. Almost
>> as bad as having to solder SMT directly to the board.
>>
>> Sockets are the answer.
>>
>> But WHERE can such things be had ?
>>
>> ANY info greatly appreciated !
>
>The ones that I am familiar with are intended as adapters
>for device programmers or prototyping. Very handy but
>relatively expensive (and large).
>
>Some examples at
>http://www.logicalsys.com/
>http://www.adapt-plus.com/products/adapters/index.html


Wow ... you weren't kidding about them being *expensive* !

On 11 Jan 2008 09:33:22 GMT, Robert Latest <boblatest@yahoo.com>
wrote:

>B1ackwater wrote:
>> It's official - I *hate* surface-mount junk. Too small
>> for human beings. I'm forever bridging connections or
>> overheating or underheating or going blind from the
>> magnifier or ... well ... you know. SMT is for ROBOTS.
>>
>> I can't be alone.
>
>I thought like that up until a year ago until I bit the bullet an sat down
>and made my first SMD board. SO8/0805/SOT-23. I used a
>temperature-controlled Weller with a fine tip, PbSnAg solder and
>occasionally liquid flux to be applied with a fine brush. The board was made
>in a board house and luckily gold-plated (they just throw the prototypes
>into their batch pool, you never know what surface finish you get).
>
>At first I was intimidated, but after a few parts I knew I would never want
>to go back to TPH. Assembly is a lot faster than TPH because you don't need
>to bend and clip leads.
>
>Given the right tools even rework is much easier than on TPH. I got the
>cheapest solering tweezers I could find, a rather clumsy Weller model that
>plugs into their standard electronic temperature controllers. It takes five
>seconds to remove a SO16 chip (but several minutes to fit and align the
>proper tweezer tips and to heat up the iron
>
>Try it, you'll love it. I've never tried this on homemade boards, but if you
>do make sure to tin the pads really well before assembly. And use extra flux
>if you reflow connections.
>
>And practise. I ripped the controller board out of a dead hard drive, baked
>it in the oven at 210 deg C for a while an then gave it a single, hard rap
>onto the tabletop. 99% of components flew right off, yielding hours worth of
>free practice components and a PCB. (even if you abhor SMD assembly, this is
>fun BTW.)
>
>There are people who say that 0.5mm pitch components are easy to solder by
>hand. After trying it with the controller chip on said harddisk PCB I can't
>conirm that, but the leads of the chip were slightly bent and unevenly
>tinned. Maybe with a new chip and PCB it is easier.
>
>Good luck!

I've tried it ... I didn't love it. Of course now I've
got a colletction of ground-down Weller iron tips that
may be good for something sometime.

Yesterday I went out and bought the RadioShack de-soldering
dohickey that's supposed to be stuffed with metal wool and
attached to an aquarium pump to create a hot-air 'iron'.
I'll see how that goes.

SMT really IS for robots. Admittedly the *necessary* size
of ICs and such is now very tiny - and this lets manufacturers
make really tiny devices like iPods and such. Thing is, it
really makes it hard for those of us who hand build prototypes
and low-volume stuff.

Maybe I should build a chip-handling robot ... XYZ mechanism
with a teeny-tiny 'spot-welder' that bonds the chip to a
pre-coated PCB ... ?

robb wrote:

> "Robert Baer" <robertbaer@localnet.com> wrote in message
> news:13oedtpchlogj4a@corp.supernews.com...
>
>> I designed a similar board for SOT-23 and the like, with
>
> DIP-8 pins.
>
>> Used some high-temp board and they are rather useful.
>> Do not know how to sell it, so am stuck with thousands of
>
> those
>
>>press-mount pins...
>>
>
> are those the pins that you press onto the side of a standard PCB
> (where there is a pad or trace contact) to give the PCB a DIP
> like appendage/appearance ? and are they the solderable type ?
>
> i have been searching to purchase some of those but can not find
> a source that sells them in small lots (ie. 500) ? i have found
> rolls (15-25 thousand) ....
>
> if you are looking to rid yourself of some of that excess
> inventory then do you sell on th-e-bay ?
>
> robb
>
>
>
These pins press fit into an 0.026 hole; MillMax 3154-0-00-15-00-00-03.
One source charged me $0.62 each for 2000 and another source charged
me $0.30 each for 15,000.
What if i just sent you the 2,000 bag (less about 140) for the
Halibut (fishy reasons) no charge?
That way a certain somebody will not have a hissy-fit about this not
being a market place (wheer fish could be found).

B1ackwater wrote:

> On 11 Jan 2008 09:33:22 GMT, Robert Latest <boblatest@yahoo.com>
> wrote:
>
>
>>B1ackwater wrote:
>>
>>>It's official - I *hate* surface-mount junk. Too small
>>>for human beings. I'm forever bridging connections or
>>>overheating or underheating or going blind from the
>>>magnifier or ... well ... you know. SMT is for ROBOTS.
>>>
>>>I can't be alone.
>>
>>I thought like that up until a year ago until I bit the bullet an sat down
>>and made my first SMD board. SO8/0805/SOT-23. I used a
>>temperature-controlled Weller with a fine tip, PbSnAg solder and
>>occasionally liquid flux to be applied with a fine brush. The board was made
>>in a board house and luckily gold-plated (they just throw the prototypes
>>into their batch pool, you never know what surface finish you get).
>>
>>At first I was intimidated, but after a few parts I knew I would never want
>>to go back to TPH. Assembly is a lot faster than TPH because you don't need
>>to bend and clip leads.
>>
>>Given the right tools even rework is much easier than on TPH. I got the
>>cheapest solering tweezers I could find, a rather clumsy Weller model that
>>plugs into their standard electronic temperature controllers. It takes five
>>seconds to remove a SO16 chip (but several minutes to fit and align the
>>proper tweezer tips and to heat up the iron
>>
>>Try it, you'll love it. I've never tried this on homemade boards, but if you
>>do make sure to tin the pads really well before assembly. And use extra flux
>>if you reflow connections.
>>
>>And practise. I ripped the controller board out of a dead hard drive, baked
>>it in the oven at 210 deg C for a while an then gave it a single, hard rap
>>onto the tabletop. 99% of components flew right off, yielding hours worth of
>>free practice components and a PCB. (even if you abhor SMD assembly, this is
>>fun BTW.)
>>
>>There are people who say that 0.5mm pitch components are easy to solder by
>>hand. After trying it with the controller chip on said harddisk PCB I can't
>>conirm that, but the leads of the chip were slightly bent and unevenly
>>tinned. Maybe with a new chip and PCB it is easier.
>>
>>Good luck!
>
>
> I've tried it ... I didn't love it. Of course now I've
> got a colletction of ground-down Weller iron tips that
> may be good for something sometime.
>
> Yesterday I went out and bought the RadioShack de-soldering
> dohickey that's supposed to be stuffed with metal wool and
> attached to an aquarium pump to create a hot-air 'iron'.
> I'll see how that goes.
>
> SMT really IS for robots. Admittedly the *necessary* size
> of ICs and such is now very tiny - and this lets manufacturers
> make really tiny devices like iPods and such. Thing is, it
> really makes it hard for those of us who hand build prototypes
> and low-volume stuff.
>
> Maybe I should build a chip-handling robot ... XYZ mechanism
> with a teeny-tiny 'spot-welder' that bonds the chip to a
> pre-coated PCB ... ?
>
Do not think you need a spot welder.
Just apply solder paste to the IC pads, do the pick-and-place, then
carefully put in an oven for reflow.
If parts need to go on other side, make sure all small parts get
reflowed on one side first, leaving the side with bigger parts
("squashed bugs" i call them) on top when reflow.
The capillary action of the (liquid) solder on the "bottom" side is
more than strong enough tohold small parts.
I have a board that holds about 78 parts on both sides; the PCB is
0.5 by 1.4 including pads for wires.
The only problems i have seen was due to one lead not being wetted
during fab.

"B1ackwater" <bw@barrk.net> wrote in message
news:4787c2e5.2567343@news.east.earthlink.net...
> On 11 Jan 2008 09:33:22 GMT, Robert Latest <boblatest@yahoo.com>
> wrote:
>
>>B1ackwater wrote:
>>> It's official - I *hate* surface-mount junk. Too small
>>> for human beings. I'm forever bridging connections or
>>> overheating or underheating or going blind from the
>>> magnifier or ... well ... you know. SMT is for ROBOTS.
>>>
>>> I can't be alone.
>>
>>I thought like that up until a year ago until I bit the bullet an sat down
>>and made my first SMD board. SO8/0805/SOT-23. I used a
>>temperature-controlled Weller with a fine tip, PbSnAg solder and
>>occasionally liquid flux to be applied with a fine brush. The board was
>>made
>>in a board house and luckily gold-plated (they just throw the prototypes
>>into their batch pool, you never know what surface finish you get).
>>
>>At first I was intimidated, but after a few parts I knew I would never
>>want
>>to go back to TPH. Assembly is a lot faster than TPH because you don't
>>need
>>to bend and clip leads.
>>
>>Given the right tools even rework is much easier than on TPH. I got the
>>cheapest solering tweezers I could find, a rather clumsy Weller model that
>>plugs into their standard electronic temperature controllers. It takes
>>five
>>seconds to remove a SO16 chip (but several minutes to fit and align the
>>proper tweezer tips and to heat up the iron
>>
>>Try it, you'll love it. I've never tried this on homemade boards, but if
>>you
>>do make sure to tin the pads really well before assembly. And use extra
>>flux
>>if you reflow connections.
>>
>>And practise. I ripped the controller board out of a dead hard drive,
>>baked
>>it in the oven at 210 deg C for a while an then gave it a single, hard rap
>>onto the tabletop. 99% of components flew right off, yielding hours worth
>>of
>>free practice components and a PCB. (even if you abhor SMD assembly, this
>>is
>>fun BTW.)
>>
>>There are people who say that 0.5mm pitch components are easy to solder by
>>hand. After trying it with the controller chip on said harddisk PCB I
>>can't
>>conirm that, but the leads of the chip were slightly bent and unevenly
>>tinned. Maybe with a new chip and PCB it is easier.
>>
>>Good luck!
>
> I've tried it ... I didn't love it. Of course now I've
> got a colletction of ground-down Weller iron tips that
> may be good for something sometime.
>
> Yesterday I went out and bought the RadioShack de-soldering
> dohickey that's supposed to be stuffed with metal wool and
> attached to an aquarium pump to create a hot-air 'iron'.
> I'll see how that goes.
>
> SMT really IS for robots. Admittedly the *necessary* size
> of ICs and such is now very tiny - and this lets manufacturers
> make really tiny devices like iPods and such. Thing is, it
> really makes it hard for those of us who hand build prototypes
> and low-volume stuff.
>
> Maybe I should build a chip-handling robot ... XYZ mechanism
> with a teeny-tiny 'spot-welder' that bonds the chip to a
> pre-coated PCB ... ?
>

Hi,
SMT by hand is easy and inexpensive when you know how. Not always just for
robots:) And you don't need to buy expensive hot-air rework stations etc.

I put alot the technqiues for SMT hand soldering in my product at
http://SuperSolderingSecrets.com There's a free membership there which has
some of the videos.

Also, there's a nice article on low cost DIY hot air rework, written by Tom
Mathews and Timothy Toroni at National Semiconductor. It's called "Rework
within your reach" http://www.edn.com/contents/images/447009.pdf
[text version at
http://www.edn.com/index.asp?layout=art ... d=CA447009 ]

Also, Schmartboard are trying to make it easier for prototyping with SMT
chips. They have a bunch of different types, for SOP, QFP, PLCC, BGA etc.
They fan out to through-hole pads, which you can solder wires or pins to &
then connect off to your breadboard
http://www.schmartboard.com/index.asp?page=products_qfp

Kind regards,
Anthony Burch http://SuperSolderingSecrets.com

On 2008-01-11, CWatters <colin.watters@turnersoak.plus.com> wrote:
>
> I once had to ask a technician (Hi Terry) if he could remove a 160 pin TQFP
> with hand tools and save both the board and the device.

You can do that with hot air[*], an oven, or Chip-Quik (a low-temp solder
you flood on the pins). It's easy if you don't care about the device,
though, just score the pins at the device and remove the pins by swiping
your iron by with a blob of solder.

[*] or a propane torch on the back, followed by a whack on the bench. Wait,
you said preserve the board??

--
Ben Jackson AD7GD
<ben@ben.com>
http://www.ben.com/