Subject: | |
From: | |
Reply To: | |
Date: | Wed, 21 May 2008 08:13:11 -0400 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Dan,
You've got some fine answers to the meaning of your question, but I
would like to check the reason of it.
What do you actually want to do? Estimate the contamination from paste
and non-RoHS components and see if you are within 0.1% Pb? If so, forget
it, this is precisely not how you assess RoHS compliance!
The contamination is checked on homogeneous material; to simplify it, if
one joint has more than 0.1% Pb, from let's say touch-up with the wrong
wire or from non-compliant finish of one component, the product is not
RoHS, regardless of the condition of all the other spots on the board
and the overall Pb percentage.
If I misinterpreted your intent, my apologies and please carry on in
your quest.
Regards,
Ioan
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Dan Mathews
Sent: Tuesday, May 20, 2008 12:10 PM
To: [log in to unmask]
Subject: [TN] Average paste volume estimate
Does anyone have an easy way to estimate how much paste is applied to a
smt pcb? I understand it varies on
squeegee pressure, stencil thickness, and pitch of the components but I
was looking for an average. I would
assume that somewhere out there someone can estimate that "2 grams of
paste is used on a 2" x 2" smt pcb".
I will then use this information to determine how much lead is used on
non-RoHS products due to solder paste
issues and not non-compliant components.
Thank You in Advance,
Dan
Dan Mathews C.I.D.+
Engineering Support Supervisor
B&B Electronics
Ottawa, IL USA 61350
Phone: 815-433-5100 ext 217
Fax: 815-434-8831 (direct to my desk)
URL: http://www.bb-elec.com <http://www.bb-elec.com/>
---------------------------------------------------
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
-----------------------------------------------------
|
|
|