Previous Blogs of mine have mentioned the need for enlarger earthing. Where possible I have felt that some of the (pre-war?) systems of serpentine time-expired leads passing through the enlarger column are best by-passed in favour of simple leads from lamp to timer.
I came across an unusual aspect of this problem yesterday while fitting in my Kodak Precision enlarger of the 1939 US type which has been out of my darkroom for some time. I reserve this machine for 6x9 prints and should explain that it is of the very attractive gray and polished alloy type with lots of stainless steel, duralumin, and nothing likely to corrode.
The enlarger was originally designed for 110 volt use with built in US 2- pin fittings to get the power to the lamp. This enlarger is not to be confused with a UK produced machine from the 1950's(and early colour machines) derived from the original, but not so visually attractive.
After fitting this in my Darkroom I tested to confirm that the supply to the head had an earth connection and found continuity with the lamp globe and its mounting. Nothing else was earthed. This strange situation resulted from Kodak's use of fiber gaskets to assemble sections of the head and copious use of black felt to prevent light leaks in the negative stage. Strange to say the insertion of a negative carrier restored continuity but heavy finish in crackle paint in parts also interfered with friction contact.
This is an unusual enlarger to see these days and it is most unlikely that anyone else will benefit from my experience but I have recorded this note to stress the dangers that old enlargers present when imported from US. Relying on friction contact with heavy paint finishes is unwise. Above all, get a professional test before switching on! And, don't forget, that 110 volt timers are usually driven by a 60 cycle motor so that the seconds, although constant, will not be good old British seconds!(and a transformer will be needed) This time difference will hardly matter for print work where any regular intervals can be worked with but could cause problems with development of films. 60 cycle mains can be replicated but the answer is not cheap-there are some suggestions on Youtube but this reference is made without liability. Back to Leica.............
Some Leica fans are dedicated to replicating the original wiring system and I see that the early German three pin plugs with V shaped pins are still available on Ebay for the brave and qualified worker.One problem will be the German wire colours of the 1950,s.
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