TECHNET Archives

May 2004

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Brian Ellis <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Tue, 4 May 2004 18:08:58 +0300
Content-Type:
text/plain
Parts/Attachments:
text/plain (124 lines)
Phil

In all the many tens of installations I have done, never once have I
used any parts that contact the flux that were not in PVC, PP or
titanium (notably fingers), other than the sintered plastic foaming
"stone". Big mistake to use brass or stainless steel, both of which are
attacked like gangbusters by the flux. I agree that a PVC air knife is
very useful for adjusting the quantity of flux, before the pre-heat.

Actually, the worst case of corrosion I have seen of a soldering machine
was not with a WS flux but with a "no-clean" of a particular brand made
in N. Europe. I was visiting a factory which had been using it for
several years for telecoms equipment. I "naively" asked the engineer
whether he was not worried about his boards corroding in service. He
replied that the flux in question was non-corrosive, bringing forth the
manufacturer's data sheet as "proof". I then asked him, equally naively,
how he explained that every bit of iron/steel was practically rusted
through in a 50 cm radius round his fluxer. He had a good look, turned
pale and said, "Mon Dieu!"!!! :-( I then asked him what qualification
tests he had done and he replied that their sole criterion was the
"no-clean" flux that soldered best. It simply hadn't occurred to him
that high-activity = high risks. I knew what to expect because I had
seen other cases with that one, particular, flux. I just checked and
this same flux is still manufactured!

Brian

Phil Nutting wrote:

> Ramon,
>
> Brass fittings in the Flux tank were eaten through, rivets on the fluxer assembly were dissolved to the point where they fell out, the stainless steel enclosure of the flux reservoir and fluxer now look rusty and the excess flux dripping off boards into the pre-heat elements have caused flash over arcs that trip circuit breakers.
>
> The solutions to date have been to change the brass fittings to stainless steel, the rivets have not been replaced, the stainless enclosures are cleaned more frequently and the air knife has been adjusted for air velocity and angle to reduce the amount of excess flux.
>
> These items sound like we have a lot a trouble with OA (or WS), but it yields better boards as Brian Ellis has outlined.  I'll take the problems to get better yield.
>
> Phil
>
> -----Original Message-----
> From: Dehoyos, Ramon [mailto:[log in to unmask]]
> Sent: Tuesday, May 04, 2004 8:27 AM
> To: Phil Nutting; [log in to unmask]
> Subject: RE: [TN] OA / RMA
>
>
>
>         Thanks Phil:
>         What parts of the machine have been eaten or corroded and what steps have you made to slow down the corrosion?
>         Regards,
>         Ramon
>
>
>>-----Original Message-----
>>From: Phil Nutting [SMTP:[log in to unmask]]
>>Sent: Monday, May 03, 2004 2:25 PM
>>To:   [log in to unmask]
>>Subject:      Re: [TN] OA / RMA
>>
>>Ramon,
>>
>>About 3 years ago we switched from a no clean flux to an OA flux.  This change was driven by a change in board washing equipment.  We had been using a Terpene & Alcohol based batch system that no one liked and switched to a closed loop DI batch cleaner.
>>The plus side has been better solder joints out of the wave and cleaner looking boards after cleaning.
>>The minus side has been that the OA flux really eats up everything in sight in the wave soldering machine.  We have accepted this as a cost of business when using the OA flux.
>>
>>The good out-weighs the bad.
>>
>>Phil
>>
>>-----Original Message-----
>>From: TechNet [mailto:[log in to unmask]]On Behalf Of Dehoyos, Ramon
>>Sent: Monday, May 03, 2004 2:19 PM
>>To: [log in to unmask]
>>Subject: [TN] OA / RMA
>>
>>
>>                Hi Technetters:
>>                Has anybody done a comparison study of RMA/OA fluxes for wavesolder?  Or any personal experiences in this regard will be appreciated.
>>                Thanks in Advance
>>                Ramon
>>
>>---------------------------------------------------
>>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 847-509-9700 ext.5315
>>-----------------------------------------------------
>>
>>---------------------------------------------------
>>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 847-509-9700 ext.5315
>>-----------------------------------------------------
>
>
> ---------------------------------------------------
> 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 847-509-9700 ext.5315
> -----------------------------------------------------
>
>

---------------------------------------------------
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 847-509-9700 ext.5315
-----------------------------------------------------

ATOM RSS1 RSS2