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Date: | Fri, 21 Jun 96 15:46:50 CST |
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I have far too many experiences with hot bar, it still leaves a bad
taste in my mouth at times. Some other potential problems:
1. hot bar warping (depends on shape of hot bar
2. hot bar sticking to parts
3. heating rate can be a problem
4. hot bar material-ceramic seems to work better than metal
5. Are you going to use no-clean fluxes? If so, seriously consider
nitrogen.
6. Your thermode temp will be much higher than your part temp.
Don't be alarmed.
7. All of the other ideas/concerns are very valid.
______________________________ Reply Separator _________________________________
Subject: HOT BAR SUMMARY
Author: [log in to unmask] at internet
Date: 6/21/96 2:56 PM
Thank you for all your responses on this subject!!
I summarized the responses and created a small list of vendors and reference
material that might be useful to some of you. I am still looking for more
information on this subject and would appreciate your comments and
suggestions. A group reported a 30,000 PPM defect rate with hot bar
soldering. I wonder if someone can comment on this!!
Crtical Factors to consider for Hot bar Application:
- Cycle Time
- Temperature Control
- Loading Mechanism (alignment)
- Pressure Control
- Tip Life
- Programming
Potential Vendor
Teka Interconnection Sys. (401)-781-5730
Unitek Miyachi (818)-303-5676.
Palomar Products (619)-931-3622
Todco General Inc. (619)-549-9229
Pace Miniwave (???)
Literature Reference
"Development in Hot Bar Reflow", by Larry Robert Circuits Assembly, Aug.
1991
"Fine Pitch Hot bar Reflow with low temp solder and thick PWB", by Donald C
Burr, Nepcon West 1992
"Hot Bar Lead Attachment Process Optimization for TAB OLB", by Foo- Ming Fu,
Larry Dodson, IEPS 1991
You may also try the following web sites:
PCMCIA sponsored PC CardLink
http://www.pc-card.com
http://www.pc-card.com:80/
AMP's web
http://www.amp.com/
SanDisk
http://www.sandisk.com/sd/educate/abc_gen.htm
Thanks
Michael Yuen
[log in to unmask]
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