Dealing with corrosion...

A friend and business associate recently asked me about how I dealt with corrosion issues in vintage computer restorations. After I created this writeup for for him, I realized it may also prove helpful to someone on this list. Here 'tis: Very bad corrosion from alkaline battery spillage: ------------------------------------------------- Pour 30% Hydrochloric Acid directly on the affected area of the board. When the foaming (along with "clouds" of vapor) stop, immediately rinse the board in plenty of cold water. Follow with a rinsing of distilled water (to eliminate any calcium in the tap waster). Dry in the open air or with mild air pressure (I use the later to speed drying). When originally told of this process, I was skeptical (even though sourced was amazed at the quantity of foaming (and clouds of vapor) from the acid treatment. But amazingly, just as he said, the acid is not on the board long enough to dissolve traces, components, etc. It works, just as he said it would! You can get 30% Hydrochloric Acid at most hardware stores. Its "common name" is "Muriatic Acid". (Wear latex gloves when handing and protective eye guards - and use outdoors or in a well ventilated area). Medium corrosion (from any source): ---------------------------------- Apply "DeoxIT D100L" sparingly to the affected area. Wait 20 minutes. Repeat if necessary. When the corrosion is completely removed, remove any excess "D100L". Apply "DeoxIT G100L" (formerly known as "ProGold") sparingly for long term protection. Light corrosion (from any source): --------------------------------- Apply "DeoxIT GL100L" sparingly. Notes: ----- "DeoxIT GL100L" - The military (and certain manufacturers) uses this "stuff" on edge connectors in sensitive system connectors to maintain excellent contact and easy removal/insertion w/o stressing boards and connectors. I've used it for years on the edge connectors of vintage computers (PDP-8, PDP-11, etc.) - and it is truly an amazing product. Works like perfection. The "DeoxIT" products seem expensive - but because you use the stuff "sparingly", a very small bottle lasts a long time. Cheers, Lyle -- Lyle Bickley Bickley Consulting West Inc. Mountain View, CA http://bickleywest.com "Black holes are where God is dividing by zero"