TECHNET Archives

September 2002

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Henry Rekers <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Thu, 26 Sep 2002 12:29:14 -0700
Content-Type:
text/plain
Parts/Attachments:
text/plain (106 lines)
I've been there.  The problem I have now is that the vendor says it's a
problem with the proflow and proflow setup.  Dek says that it is a problem
with the paste.  (I tend to agree with dek from what I have seen.)  The
problem is that we chose this paste due to its reflow performance.  It is
very very good.  However, our evaluations were done with squeegees because
it is very difficult to obtain samples in proflow format.  My first choice
is to make this paste work, but if we have to look elsewhere, we will.

Thanks.

Henry.

-----Original Message-----
From: Jowan Iven [mailto:[log in to unmask]]
Sent: Wednesday, September 25, 2002 10:26 PM
To: 'TechNet E-Mail Forum.'; 'Henry Rekers'
Subject: RE: [TN] Viscosity vs Temperature.


Hi Henry!

I've run into similar problems with the proflow system.
We also had very good results with normal squeegees and poor results with
proflow.
I started a "Design of Experiment" to figure out what the reason could be.
Very interesting data came out of the test , but not a solution.

One very important parameter was deliberately not included in the test.
The solderpaste.
I just wanted the system to work with our standard solderpaste.

When the conclusion was that our standard solderpaste failed in the
proflowsystem, I started additional test with other pastes (types and
brands).
The results look very promising for now.
Several pastemanufacturers are capable in producing a solderpaste that works
well with Proflow.
Contact your current supplier and you will probably find a solution
together.


Best regards,

Jowan Iven
Process Engineer
Dept.   Engineering & Technology
Stork Electronics BV


-----Original Message-----
From:   TechNet [mailto:[log in to unmask]] On Behalf Of Henry Rekers
Sent:   donderdag 26 september 2002 0:45
To:     [log in to unmask]
Subject:        [TN] Viscosity vs Temperature.

We are having some issues with a new solder paste.  The evaluations came out
extremely well at first.  However, upon using it for some trial runs, we run
into some problems.

In our DEK profolw the prints look very good at about 20 deg C.  Throughout
the day, the temp in our facility climbs to 28 or even 30 deg C.  The prints
then start to bridge and flux bleeds out onto the board.  We can compensate
for it to about 25 deg by reducing the proflow pressure and wiping on every
print, but beyond 25 deg, nothing helps.

By the time the 3rd shift rolls in, the temperature starts to drop again and
the prints become more managable again.

Here's the kicker, we use this same paste on our MPM with squeegee's and the
print works every time.  There is never a print problem vs temperature.

Has anybody ever run into this situation?  How did you solve it?

Thanks in advance.

Henry J. Rekers
Manufacturing Engineer
Power Measurement.

----------------------------------------------------------------------------
-----
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
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/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700
ext.5315
----------------------------------------------------------------------------
-----

---------------------------------------------------------------------------------
Technet Mail List provided as a free service by IPC using LISTSERV 1.8e
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/html/forum.htm for additional
information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------

ATOM RSS1 RSS2