Hi Inge
Very good point. That represents another case where the assembly industry was backed into a corner by the limitations of both PCB materials and the soldering process.
Thanks for pointing that out.
Best regards,
Joe
-----Original Message-----
From: Hfjord <[log in to unmask]>
To: 'TechNet E-Mail Forum' <[log in to unmask]>; [log in to unmask]
Sent: Thu, 28 Feb 2008 10:29 am
Subject: SV: [TN] SV: [TN] Do it yourself Occam assembly
Joe, I'm surprised, that nobody added a solderless technology that is
idespread and used already. PRESSFIT !!! We have bought a machine that
nserts 600 pin connectors in just seconds. I'm in a group that makes some
tudies in future assembly technologies. We predict, that there will come
ome sort of platforms very like BGAs, but with pressfit instead of solder
alls. Furthermore, we expect there will also come a micropressfit
echnology for semi packages, inductors, caps, potentiometers etc. The
isadvantage with a all-pressfit board will be the assembly speed. A
ricsson mobile telephone board is typically chip shooter mounted in 30
econds and soldered in a couple of minutes. Pressfit will probably never be
hat fast...
Inge
----Ursprungligt meddelande-----
rån: TechNet [mailto:[log in to unmask]] För Joe Fjelstad
kickat: den 26 februari 2008 23:04
ill: [log in to unmask]
mne: Re: [TN] SV: [TN] Do it yourself Occam assembly
Thanks Inge
Yours is exactly the kind of thinking that is required to get us beyond the
roblems our poor beleaguered industry faces.
All of what you list are certainly candidates for inclusion in a future
orld of solderless assembly. I trust that you have sparked some new
hinking here as well.
Best regards and wishes,
Joe
----Original Message-----
rom: Hfjord <[log in to unmask]>
o: 'TechNet E-Mail Forum' <[log in to unmask]>; [log in to unmask]
ent: Tue, 26 Feb 2008 11:59 am
ubject: SV: [TN] Do it yourself Occam assembly
Joe, you should change name to Joy ! And found the company 'JoyToys', if not
ready established.
ight you are
nish will soldering
me will else
oda)
ut I don't think all soldering will be superseded by alternative methods.
olderfree connecting has indeed existed for decades:
hickfilm hybrids with conductive adhesives, as you pointed out.
rillions of semi chips have been scrubbed to the header.
AG laser spot welded components
acuum metal deposition
lasma metallization
lating technologies
hemical metal joining
lectron beam spot welding
eamlead welding
malgam technologies
lectric discharge welding
riction welding
ire bonding
old stud bumping
ltrasonic technologies
tc.
ho knows, maybe one of these technologies will be developed for mass
oduction of boards, or rather something that reminds of today's boards.
Inge
----Ursprungligt meddelande-----
ån: TechNet [mailto:[log in to unmask]] För Joe Fjelstad
ickat: den 26 februari 2008 18:49
ll: [log in to unmask]
ne: [TN] Do it yourself Occam assembly
reetings folks,
have tried to sidestep most of the controversy associated with Occam and
olderless assembly as much as possible to focus on getting projects done.
owever some controversy is, I suppose, good as it keeps interest alive. As
ogi Berra might have noted: "If it wasn't controversial, everybody would
t
op to avoid talking about it"... ;-)
I thought it might be worth while to give everyone here a way to make
eir own Occam type assemblies using legacy through hole components at
eir
sk in a matter of minutes. This will allow folks to form their own
inions
to the fundamental viability of the concept for the future.
is is only for demonstration purposes but I trust it will open some
nds
the possibilities that exist in the fundamental concept. The following
ll work for one or more metal layers but designs should be kept simple
r
actical reasons.
Obtain a piece of corregated cardboard box (Option: draw your
rcuit
yout on the surface)
Tape a piece of clear polyethylene (a half a common sandwich bag will
) to the cardboard
Place a second larger piece of card board underneath to keep the desk
r other surface clean
Clip the leads down slightly (one can intuit for themselves how much
clip off)
Push the leads through the polyethylene into the card board at (the
lyethylene should seal the leads reasonably well but there might be some
all leakage to the card board) Pin holes might be required as starters
r many
aded devices. Shorter clipped leads will be easier.
Cut a hole in another piece of cardboard that will encompass the
mponents and provide a resin dam wrap polyethylene around the exposed
ges
his step is optional depending on size of the assemlby)
Mix up some 5 minute epoxy and pour over components (try not to get
o many bubbles entrained)
Remove the assembly and trim the leads as necessary
Using a silver ink pen (available from some circuit equipment
oviders) draw your interconnections between contacts
) If cross overs are required, use some nail polish at the
tersection.
t can be used for cover coating if desired.
) Attach battery and go have some fun. :-)
tes. 1) If you want to include connectors, have the mated portions in
em in case some wicking occurs.
Small batteries (or screw top battery holders) can be embedded if
sired.
Dome switches are a low profile choice.
A piece of 100 mil center "bread board" without plated through holes can
e used in place of the cardboard for greater placement accuracy if that is
f interest.
The process will work for SMT devices as well but the devices need to be
ept flat and a sanding step will likely be required to clean off resin
om
ntact surfaces.
The conductivity of silver ink is about 10% of copper so stay away from
igh power designs. (keep it simple)
is is obviously not a production technology but it does provide a simple
emonstration. I sent Steve Gregory a photo of a simple assembly for those
terested to view what such a simple assembly looks like and he has kindly
onsented to post it. Here is the link:
tp://stevezeva.homestead.com/files/Through_hole_Occam_prototype.jpg .
could also serve the needs of some hobbyists and could be a fun project
r anyone having children interested in electronics.
ile I appreciate the skepticism of those who question the potential of
lderless assembly, including many long time friends whom I respect and
ld
ar. I trust that there will be some increase in acceptance of the concept
ith the data that we are in the process of generating.
may well be that the final versions of Occam assemblies will not look
ry much like today's assemblies. They could well appear to look more like
etal jacketed bricks with interconnections on the surfaces to which other
sembly elements (keyboards, displays, etc.) can be joined using other
lderless
chniques such low profile connectors or conductive and/or anisotropic
nductive adhesives.
e brick like structure should also prove great for product design
curity. Remember when Apple announced the I-Phone last year? 3 days
ter there
s a public tear down of the product design an everyone could see what was
oing on. It will be much more difficult with the solderless brick
proach.
rtunately, wholesale change within the industry is not required for the
ocess as identified. The equipment, materials and chemistry exist for
ery
ocess required. More importantly, there are some new materials and
ocesses on the horizon that appear extremely well suited to the
lderless
proach.
other point that needs to be addressed related to the process
vironment.
number of folks have registered alarm or at least concern at the thought
having plating equipment under the same roof as pick and place equipment
or vise versa). To allay such concerns, one need only go to just about any
B
op in the world to see precision equipment (drills, lasers and imaging
uipment) under one roof with a plating shop. The process areas are
ysically
d environmentally separated of course. The PCB industry has operated in
ch a fashion since the 1960s.
anging topics, I found the following quote from a Test and Measurement
rld article from October of last year.
tp://www.tmworld.com/article/CA6482921.html
n 1999, Stig Oresjo, then of Agilent Technologies, conducted a major
udy
solder-joint defects on printed-circuit boards (PCBs). The study, which
the time provided the most definitive data on the subject, involved 15
mpanies and more than 1 billion solder joints. Oresjo concluded that
though
mpanies claimed defect levels in the range of 75 to 150 defects per
llion
portunities (DPMO), the reality was 5 to 10 times that high."
Oresjo's original study, he found the following defect distribution:
41% Solder Opens
) 20% Shorts
) 20% Solder Quality
) 8% Placement
) 8% Electrical
3% Other
appears that almost 80% of the problems are related to soldering (90% if
he 8% for placement is included but I am sure it is much better these
ys.)
e 8% electrical problems cited are, I assume, parts related problems of
specified cause.
ile on the subject of electrical failures, does anyone here have any data
n how many components are damaged by the temperatures associated with the
oldering process? Also how many of the electrical failures might have been
aused by poor cleaning? I have heard a lot of anecdotal information but no
ard facts. I guess I am wondering, has there been an identified and
asured
fect of the lead-free assembly on first pass product assembly yield
mpared
tin-lead solder?
would prefer an open forum answer to these questions but I realize that
ere might be some discomfort so if anyone prefers to respond off line,
at
fine. Thanks in advance for any input on the topic.
st wishes to all and have some fun with the table top solderless
sembly...
e
**************Ideas to please picky eaters. Watch video on AOL Living.
ttp://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-du
y/
50827?NCID=aolcmp00300000002598)
--------------------------------------------------
chnet Mail List provided as a service by IPC using LISTSERV 15.0
unsubscribe, send a message to [log in to unmask] with following text in
e BODY (NOT the subject field): SIGNOFF Technet
temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
arch the archives of previous posts at: http://listserv.ipc.org/archives
ease visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
r additional information, or contact Keach Sasamori at [log in to unmask] or
7-615-7100 ext.2815
---------------------------------------------------
--------------------------------------------------
echnet Mail List provided as a service by IPC using LISTSERV 15.0
o unsubscribe, send a message to [log in to unmask] with following text in
he BODY (NOT the subject field): SIGNOFF Technet
o temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
o receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
earch the archives of previous posts at: http://listserv.ipc.org/archives
lease visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
or additional information, or contact Keach Sasamori at [log in to unmask] or
47-615-7100 ext.2815
----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
