Rob Yes I do. Unfortunately since the NPL is now a "Commercial Enterprise" with Government support, in other words they sell unpublished info. which is what this is. However, the copies run only around $35 each. Contact: [log in to unmask] I will happily send you some extracts and other support data if you can give me your SnailMail address please. As to your question about flux density, we have evidenced a lowered SIR dependant upon the amount of flux residue present. However, as I am not clear about your question, could you please elaborate? Regards, Graham Naisbitt [log in to unmask] Concoat Ltd Alasan House, Albany Park CAMBERLEY GU15 2PL UK Tel: +44 (0) 1276 691100 Fax: +44 (0) 1276 691227 ----- Original Message ----- From: Rob Watson <[log in to unmask]> To: TechNet E-Mail Forum. <[log in to unmask]>; Graham Naisbitt <[log in to unmask]> Sent: Monday, June 21, 1999 5:08 PM Subject: Re: [TN] Spray fluxing...........How do you do it right > Graham, > Do you have access to the study results from NPL? I would like to see that > study. I would like to know what the effects are of too much/little flux > applied. Also, do you know how flux density plays a part in solder joint > reliability? > > Thanks in advance, > Rob Watson > Sanmina Corp. Plant 10 > Durham, NC > > > Graham Naisbitt wrote: > > > Neil, > > > > I presume from your posting that you are not cleaning after soldering. > > > > I would strongly recommend that you try and keep the amount of flux applied > > under some control. As all fluxes leave residues, the way in which these > > react can lead to unpredictable or at least undesirable reliability issues. > > > > The NPL in the UK have completed a study which shows the amount of flux > > used, grossly affects reliability. > > > > Of course if the product is of low consequence then this may not be > > relevant. However, if you are producing something that is HiRel or Safety > > Critical, then maybe it is relevant. > > > > Might be a good idea to then validate your production process to yield the > > best results and then keep it under control. Try IPC-J-STD-001 Appendix > > D.Regards, > > Graham Naisbitt [log in to unmask] Concoat Ltd > > Alasan House, Albany Park > > CAMBERLEY GU15 2PL UK Tel: +44 (0) 1276 691100 Fax: +44 (0) 1276 691227 > > > >