This may sound like a strange answer, but if your surface prep material has
a know "plate up" thickness and you have a desired finish thickness in mind
couldn't you just change or adjust the manufacturing characteristics of the
conductors size at the production level to compensate for the known loss of
thickness from the tin?  I'm not sure if that will cause a problem with
function because I don't know what the finished product is for,(Nor would I
if I did)  but could this solve your problem without trying to change or add
another finish or process that might not be as suited to your needs?

Steve M.

----- Original Message -----
From: "Mel Parrish" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, December 09, 2002 14:07
Subject: [TN] Conductor reduction


> I would pose this to the LF forum but most of the people contribute to
both
> and some might benefit from the discussion here.
> This is a question posed to me and to tell the truth I had not considered
> it. Just never came up until now.
> "With the use of Lead Free (high Sn) solder alloys to pretin and prepare
> fine (small) conductors, we have experienced unacceptably reduced
conductor
> diameters which was not the case with standard Sn63 alloys and the same
pot
> temperature." My hunch is that the increased Sn content is the culprit,
and
> as such, is there a lead free alloy that would support a consistently
> solderable surface preparation while not introducing lead or contributing
to
> reduction of the conductor? Any experience or recommendations?
>
> Mel Parrish
> Director, Training Materials Resources
> Soldering Technology International
> 102 Tribble Drive
> Madison, AL 35758
> 256 705 5530
> 256 705 5538 Fax
> [log in to unmask]
> www.solderingtech.com
>
> ---------------------------------------------------
> 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
-----------------------------------------------------