Eddie, Here, here, I couldn't agree with you more! The only problem I have with HASL is the board warpage issue. It maybe okay for .04" thick boards, but when you start getting down to the .015" thick boards it does become a hassle (pardon the pun). I am still in the process of looking at alternative coatings for our product, and am currently evaluating the Silver Immersion coating. I am very pleased so far with some of the results I am getting, but still have a ways to go. Just my two cents. Thanks, Kathy Palumbo > ---------- > From: Eddie Brunker[SMTP:[log in to unmask]] > Sent: Friday, April 17, 1998 1:52 AM > To: [log in to unmask] > Subject: Re: [TN] PWB Surface Finishes and Solderability Conference > > Thanks for the reply, > > I'm sorry for the abrassive manner with which I put my comments foward. > I'm > passionate about this industry, love the work etc.. > I feel there is too much misinformation in our industry though. It is > generally related to having a product to sell. > > The new wonder finish is like the miracle way to loose weight without > having > to go on a diet. > I'm aware that some OEMs have an issue with board finish. > > Consider the following scenario:- > > Manager/sales staff of OEM meets Manager of customer/design house. > > Yeah we can build that! > > Manager brings board back to Engineers and says we are going to build > this. > > Engineer says the pad dimensions are totally inadequate we should have > some > input into the design stage to help the customer design his assembly for > manufactuability. > > Manager says no, no, no! We might put our customer off if we did that. > > Decision is made to use flat finish to try to improve the adhesion of wet > paste to the pad while printing, as there is such an inadequate pad > dimension/geometry. > > The fact is if the product is designed with adequate pads then ordinary > HASL > finish does the job well. > > Unfortunately there is no drive to push design for manufacturability, > probably because there is no company to benifit. > > We don't need a miracle cure, WE NEED EDUCATION. > > There is one major defect with HASL that is it's dome of solder. This > presents us with no problems at 20 thou pitch on connectors, QFPs and > SSOICs. > > Don't fall into the trap of trying to create flat HASL finish either. You > run into other problems. > > The cleanliness aspect may be a factor for some too. But I'm sure this can > easily be addressed by talking to the suppliers about the flux technology > and cleaning methods. > > Thanks again, > > > > At 16:10 16/04/98 -0500, you wrote: > > and yes, there was a bit of > >HASL-bashing, but it was mainly done by the OEMs and assemblers, they are > not finding > >it to be acceptable. > > >I must tell you that no one is advocating HASL to me for the next > generation of > >surface mount PCBs. The conventional wisdom being (you might disagree) > that > the pads > >are simply not planar enough. HASL's advantages and disadvantages are > fairly well > >understood, which may be another reason why no one wants to do a > presentation on it > >at my conference. > > > > > >John Riley > >Director of Education > >IPC > >2215 Sanders Road > >Northbrook, IL 60062-6135 > >(pho) 847-509-9700 ext. 308 > >(fax) 847-509-9798 > > > > > > > > ################################################################ > TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c > ################################################################ > To subscribe/unsubscribe, send a message to [log in to unmask] with > following text in the body: > To subscribe: SUBSCRIBE TechNet <your full name> > To unsubscribe: SIGNOFF TechNet > ################################################################ > Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional > information. > For the technical support contact Dmitriy Sklyar at [log in to unmask] or > 847-509-9700 ext.311 > ################################################################ > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################