Hey Ed!
I know he maybe trying to save money, but daily de-drossing is pretty
standard as far as I know. You've been here at my place, and at least we do that.
It might be time for a pot change-out. A lot of work, but will reap many
rewards as far as defects are concerned. I assume that they have the pot
analyzed regularly.
It isn't as expensive as one might think, you can re-cycle the solder, but
it is a bit of work. If one takes the advice that Ed once gave me, use "Bakers
Secret" Teflon coated loaf pans, (Get about a dozen of them) you can make
the nicest solder ingots that you have ever seen....I posted a picture of them a
while back when I drained a 1,800-lb pot of solder all by myself (An
Electrovert Electra Pot).
For a Trieber, make sure you dis-connect the electrical connections for the
top fire-rods once the solder goes below them (You don't want them to start
glowing red), and the same goes for the lower rods...you need to be quick
about removing the solder.
Ed has shared with me about all the the little "Tricks" what one needs to do
when doing something as major as changing out the solder in a wave solder
machine, his advice is sound....he's been there, and done that, countless times.
Time to change the pot out...
-Steve Gregory-
In a message dated 10/22/2004 7:09:36 PM Central Standard Time,
[log in to unmask] writes:
Hi 'netters,
I have a client with an uncommon problem and seek some suggestions.
For the past year, the wave solder operator has been trying to "save the
company money" by stacking the dross in the rear of the dual wave Treiber pot.
He perceived that the dross was dissolving back into the solder as the 6" high
mound would drop to about 2", ready for the next load, repeat.
Unfortunately, the truth is the weight simply pushed the dross down to the bottom of the
pot where the impellers chopped it into fine particles and placed them into
suspension throughout the body of the solder.
Most processed boards looked OK, but a recent new design with large (1/2" x
1/2" x 1/8") terminals on the bottom of the board showed dross inclusions
embedded in the soldered surface.
The surface of the wave has small particles of dross flowing with the
solder, even after dedrossing the nozzles, and letting the pot sit undisturbed
while turned on for several days hoping the particles would float to the surface.
A so called industry expert said it will simply go away by itself, but it's
been over 2 months and the sandy appearance in the wave persists, along with
the embedded inclusions. I believe the solder is ruined and should be
replaced.
If anyone has seen this before, please let me know what you did to resolve
it.
Regards,
Ed Popielarski
QTA Machine
949-581-6601
---------------------------------------------------
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
-----------------------------------------------------
|
