Anti Corrosion for Electromechanical Things....

Worth investigating VCI paper and emitters! Taken from VCI-Paper.com; (worth noting "VCI" is not a brand, it stands for Volatile Corrosion Inhibitor) If you purchase something delicate, or have something machine - it might come packaged with brown paper - chances are that's VCI paper - keep it!

VCI Emitting Devices

VCI EMITTERS extend the working lifetime of electronics, reduce corrosion of all types of metals inside panels, circuit boxes and enclosures. VCI Emitters are compact devices available in open cell foam, sheeting, pouches, sachets, pipe inserts or easy to install adhesive backed domes. VCI emitting devices protect switch gear, electronics, enclosed packages, piping and electronic panels. Dome style inserts are made of a sturdy, moisture resistant poly.

Edited By Russ B on 09/07/2014 13:43:45

Edited By Russ B on 09/07/2014 13:44:37

If you have to...use a conformal coating -aerosol or dip- a product proven to be compatible with electronic components on the boards. If you have to dry out electronics use IPA but watch out for some capacitor types especially polystyrene, don't use a product intended for petrol engines. I would not apply anything to the mechanics at all other than the reccomended lubricants.

However VTR's should not be exposed to corrosive /dusty conditions if you want it to continue working, it begs the question WHY ?

If it is long term storage then silica gell desicators and a plastic container- even a bag- is better than nothing. If there is corrosion already then it is too late but dessication will minimise further corrosion.

WD40's formulation varies in different places and at different times, but it is simular to white spirit, light mineral oil and a perfume, that is what they declaired in the UK in a MDS some years back. So you cannot say with certainty that this liquid is long term safe on copper/tin/lead/aluminium/plastic but it will remove specialised lubricants from bearings that have very small amounts of lubricants.

Billy.

VPI,' Vapour Phase Inhibitor' is very good and as long as the item is air tight and dry. Another way is to seal the item in and air tight container and suck out the air and replace with Nitrogen. This is an inert gas and often used in optical systems that are sealed and used in adverse conditions, an example are binoculars and Sighting telescopes used outside in all weathers. At one time we had a machine that, 'Burnt' the air that was cycled through the instrument and this was to kill fungus. Later small tabs were put in instruments that were anti fungus.

Clive

Don't over think it. Dust it off, pull the panels an make sure all the innards are clean, quick squirt of contact cleaner on any exposed connectors and wrap it tightly in a heavy plastic bag. Include a dessicant pack to if you have one. Put the whole shebang in a heavy cardboard box or plastic tub. Seal well with tape and job done.

Best would be to use the heavy anti-static lined bags made for electronics stuff and suck out all the air using one of those vacuum widgets. But the proper bags are hard to find individually, they are a clear plastic and look like a normal bag not the usual small foil ones computer bits come in. Unconvinced by the cheap vacuum thingies as the one time I tried things didn't go well.

I've known bagged' boxed lab electronics gear to work just fine after several years container storage. Don't overlook the heat aspect. Ordinary shipping containers can get very hot inside if badly sited. When used for long term storage they should have vents and a fan, ideally lined as well.

Clive

I recently powered up a couple of switched mode power supplies that I had stored on a shelf in the outside garage for at least 19 years (before our daughter was born). They were stored without any particular precaution and were designed for building into OEM equipment ie semi-open and peppered with large obround slots. Apart from blowing out the spiders webs and checking there weren't any obvious pieces of swarf hanging out, I didn't do anything other than turn them on.

The electrolytic bus capacitors usually need to be repolarised after being unpowered for more than a few years but that happens when you power them up again. I was glad to see that they both worked fine.

Putting equipment into plastic bags can actually be counterproductive unless you hermetically seal them. During humid weather, as the ambient temperature cycles each day, you can start to accumulate condensation inside the bag that has no means of escape. Don't ask me how I know. Silica gel is no use in this situation, as it rapidly becomes saturated and ends up as a funny blob of jelly in the resulting puddle.

You may be better off simply covering your equipment to prevent spillage and swarf getting in. Apart from conductive contamination, there is little that will cause any deterioration unless you store it out in the weather.

Murray

When storing aircraft engines, inhibiting oil is sprayed into the cylinders, and dummy sparkplugs put in the plug holes, these plugs contain silica-gel, I had a set, but gave them to a spark plug collector, along with a collection of aero-engine spark plugs. Ian S C

After my apprenticeship I joined the maintenance Dept as a Machine Tool Fitter and after a few years progressed to the Reliability Engineering Dept who responsibility was to look after the long term maintenance, refurbishment and upgrade of all types of machine tool from small lathes, multi spindle lathes, milling machines, all types of grinders including centerless, cylindrical and surface.

A factory was set up to supply parts to America until a manufacturing facility was established in the USA, when the American plant was up and running the UK plant was shut down, as the machinery was not very old it was all stored for future use and to help with the preparation all of the machine tool manufacturers, mostly European came in and cleaned, changed lubricants and sprayed all metal surfaces with anti corrosion wax they were then shipped to a storage facility, an old aircraft hanger and it was my job to finish the storage which involve laying a damp proof layer on the floor then placing a heavy gauge plastic sheet large enough to completely enclose the machine, more padding so as not to damage the plastic sheet followed by the machine, the plastic sheet was then covered over the complete machine and sealed with welding guns to turn the sheet into a bag. Before sealing up completely several large bags, weighting several pounds, were placed inside and then the bag had as much air as could be removed was sucked out and the bag sealed completely.

I spent nine months in total in the hanger and I received up to four machines every day for approx 200 days not including weekends and when I left the site the first machines put in were still in good condition with the plastic still tight, any that had leaked were resealed once we had found the original leak.

I dont know what happened to the machines as I left six months later.

Martin P

It is helpful when using dessicators to include a colour change indicator in the bag to check the seal effectiveness. I don't see the issue with sealing up an Ampex, you use the appropriate bag or as Martin has said make one. As Muzzer has found out it is a waste of effort NOT to seal a bag with dessicator, hardly difficult to predict. A very effective bag seal can be made using 3M 467 transfer adhesive in 1" strips if you can't heat seal. But many shipping grade single and double sided tapes dry out and become useless within a few months.

VTR's are not quite the same as Machine Tools, you cannot spray oil or wax all over. Would suggest that the people at WWW. BATC.ORG.UK would be a very good souce of info if you are not already a member.

Billy.

Up until about 10 years ago I helped a friend restore, and rebuild Willys Jeeps (WW2), he got a load of "new" parts from the Philipines, they had been buried in the jungle during the war, wrapped in tar paper, all except a few that the packing was damaged were OK, no corrosion, and that in a tropical jungle. Ian S C