Thread: Paint on Microscopes - How did they do it?

I was just looking through my saved photo collection and dwelled a while amongst the microscopes. The painted surfaces are perfect and durable. I have a Bausch and Lomb microscope from the mid fiftes. The paint finish is flawless.

Anyone know how this perfection was achieved?

BT

BT, agreed. I've had one of those Leica Mics through my hands over the years - I wondered if they had been coated in an electrolytic spray painting process - charged plate. You're right - they're silky smooth

Mark

I think they used baked Enamel,there was a kot of that done ib the early years.

Eddie

I was just reading a google books 1939 popular mechanics on microscope restoration. The author used baking enamel which he claimed had a plastic pigment which flowed under heat. I guess it was an evolution of the japanning process.

I wonder about instrument lacquers?

GQ

Hi BT,
Not that they dont look nice, but its not like they have been out in the rain for 60 years. My father has a microscope that has likely spent more than 99.995% of the last 50 years in its box at the back of the cupboard


+1 for bake Enamal(but only because I used it long ago... there maybe other things)

Stuart

http://www.microscopy-uk.org.uk/mag/...scopes7rev.pdf

"We are not sure whether Leitz was using porcelain enamel (a substantially vitreous or glassy inorganic coating bonded to metal by fusion at a temperature above 800°F)."
Interesting - wouldn't heating have introduced possible distortion?

Mark

I got to thinking this morning that I cannot recall ever seeing a less-than-perfect finish on everything medical/dental. From otoscopes to giant x-ray machines. Same goes for the brightwork. There must be some secret guild of scientific apparatus finishers somewhere.

Greg

Originally Posted by Greg Q

I got to thinking this morning that I cannot recall ever seeing a less-than-perfect finish on everything medical/dental. From otoscopes to giant x-ray machines. Same goes for the brightwork. There must be some secret guild of scientific apparatus finishers somewhere.

Greg

I squandered an hour this morning searching for precision paint finishing, bake enamelling, painting cameras and so on. How to paint your Nikon pink cropped up all too frequently. I reckon it has to be some baked on finish.

There was some discussion on a camera buff forum about black painted rangefinder Nikons. Black being rarer than chrome and therefore being more sought after, has led to fakes entering the collectable market. The comment was made that there would be no more than half a dozen people in Japan capable of achieving a factory like finish.

A lot of previously painted metal parts have been replaced with plastic. Maybe paint finishing is disappearing?

Here are a couple of SP Nikons. The one in good nick is available for $13,299 "Buy I Now", the beater, $4298. You can see why there would be an interest in DIY painting.

BT

Originally Posted by Greg Q

I got to thinking this morning that I cannot recall ever seeing a less-than-perfect finish on everything medical/dental. From otoscopes to giant x-ray machines. Same goes for the brightwork. There must be some secret guild of scientific apparatus finishers somewhere.

Greg

One of my uncles had a business making dental tools mainly for the US market with most of the manufacturing coming out of one his factories in Caracas. Their stuff was always immaculate but from what I remember labour was cheap which was fortunate because there was at the time a lot manual and polishing work involved.

Just emerged from a review of the Yahoo Microscope restoration and collection group -

"In most cases, it is alkyd enamel, the same stuff used to paint cars before the
advent of "acrylic." Alkyd enamel is relatively soft, and has good chip
resistance.

However, there are exceptions. American Optical switched to epoxy paint before
1960, with the Cycloptic line. They were probably the first.

Polyurethane paint was first used in WWII on some aircraft. In the early 1960's,
the polyurethane industry expanded rapidly. Polyurethanes are more chemical
resistant than alkyds. My Leitz Orthoplan frames, dating to 1964, are painted
with polyurethane."

Searching "scientific apparatus restoration" yielded an expired ebay listing for this book: i emailed the seller to ascertain if it sold or just expired.



La restauration et la conservation des appareils scientifiques de collection : = Restoration and preservation of scientific apparatus for collections

Author: Guy Biraud; Jacques Le Breton; Richard Foster; Societ́e ́Historique de Radio.
Publisher: [Fontenay, France? : Edition Biraud, ©1987]
Edition/Format: #Book : EnglishView all editions and formats
Rating:
(not yet rated) 0 with reviews - Be the first.

I read a comment about the introduction of paint to surfaces that previously were exposed brass. The paint saved a lot of labour. Not hard to see why. Below is a photo of a Bausch and Lomb " The Grand" microscope from 1898, part of a collection belonging to Allan Wissner. Worth a look if you are interested in this stuff.

http://antique-microscopes.com/

BT

Not that I'm becoming obsessed, but HSU SciInst Lit-Author includes an interesting text "I Saw Them Making Microscopes". p12 details "men were spraying microscope parts with enamel. . . . .electric ovens for baking enamel". The other texts feature Bausch & Lomb (under subheading Microscopes)
Mark

Originally Posted by Greg Q

I got to thinking this morning that I cannot recall ever seeing a less-than-perfect finish on everything medical/dental. From otoscopes to giant x-ray machines. Same goes for the brightwork. There must be some secret guild of scientific apparatus finishers somewhere.

Greg

I remember reading in a book on the Cambridge Scientific Instrument Co. (of which I own a number of beautifully laquered meters) that the finishing process on brass involved one old man, a secret recipe of shellac, and a camel hair brush, and that he died, and the secret went to his grave with him.

One thing that I do know is that the crackle finish on microscopes was baked at a low temperature, around 150 DegC. It had to be, since some of the brass components were soft soldered.

I always marvel at the finish of old instruments, and I take my hat off to the craftsmen who made them.

Greg: Lens making actually was a guild until recent times