Cheryl,
This is very good information that many of us need. Thank you so much
for sharing this with us!
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Cheryl Tulkoff
Sent: Monday, December 12, 2005 8:17 AM
To: [log in to unmask]
Subject: Re: [TN] Preparing Solder Pot for Lead Free Processing
Chris -
We cleaned an existing tin/lead cast iron solder pot (Electrovert) and
converted it to lead free with excellent results - verified by
analytical reports for various contamination levels.
We simply drained the pot, gently scrubbed and vacuumed, and replaced
all the internal parts (pot drain valve, sumps/pumps/baffles). We also
installed new finger brushes, conveyor chains, and fingers. The
preheaters and housing areas were all vacuumed and wiped down as well.
Tin "wash" procedure have been talked about but they are a pricey way to
go. They basically involve using an initial sacrificial 100% tin bath
and redrain (recycle) before final filling with your lead free alloy.
The procedure from Speedline is cut and pasted here:
SCOPE: LEAD FREE UPGRADE PROCEDURE
ELECTRA / VECTRA
METHOD:
1. Remove all nozzles, flowducts, pumps and all other
components
that are in the pot. Use
protective equipment while performing this
task.
2. Leave heaters on while draining solder.
3. Drain solder from the pot and scrape the sides and bottom to
remove any solder residue and
dross.
4. This procedure will provide a contamination level
well below the required specification as
long as the pot was cleaned properly.
5. Change the solder pot configuration to lead-free. See the
Software Configuration Manual.
6. Fill pot with lead-free solder and allow the solder to melt
and
reach the setpoint temperature.
7. Once solder has reach the setpoint temperature de-dross the
pot.
8. Install the new lead-free flowducts, nozzles,
pumps
and other parts in the lead-free upgrade.
The existing belts and pulleys and covers will
need to be used. Use protective equipment when
performing this task.
9. Using the nozzle setup tools, level nozzles and make sure
the
pumps are seated.
10. Have solder analyzed to ensure lead levels are below
specification.
Thanks,
Cheryl Tulkoff
Senior Reliability Engineer
Phone:(512) 683-8586
Fax: (512) 683-8847
National Instruments
11500 N. Mopac Expressway
Building A
Austin, TX 78759-3504
"Schaefer, Chris"
<Chris.Schaefer@S
UNTRONCORP.COM>
To
Sent by: TechNet [log in to unmask]
<[log in to unmask]>
cc
Subject
12/12/2005 07:58 Re: [TN] Preparing Solder Pot for
AM Lead Free Processing
Please respond to
TechNet E-Mail
Forum
<[log in to unmask]>
; Please respond
to
"Schaefer, Chris"
<Chris.Schaefer@S
UNTRONCORP.COM>
Thank you all.
So should I do one of the following:
- Replace the solder pot altogether (the safest method, but most
expensive)
- Clean the existing cast iron pot as best possible then fill with Pb
Free solder (higher risk, but less expensive)
If anyone has cleaned their existing cast iron solder pot, then how did
you do it exactly? Is there a proposed method for doing this somewhere
out there?
Any suggestions would be very helpful.
CAS
-----Original Message-----
From: [log in to unmask] [mailto:[log in to unmask]]
Sent: Fri 12/9/2005 11:10 AM
To: Schaefer, Chris; [log in to unmask]
Cc:
Subject: Re: [TN] Preparing Solder Pot for Lead Free
Processing
Hi Chris,
Pb left in the old 'pot' may not be your biggest
problem--look at these pics.
Regards,
Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability
Consulting
7 Jasmine Run
Ormond Beach, FL 32174 USA
Phone: 386-437-8747, Fax: 386-437-8737, Cell: 386-316-5904
E-mail: [log in to unmask], Website: www.engelmaier.com
---------------------------------------------------
Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
