Mustafa Umut Sarac Posted September 17, 2012 Share #1 Posted September 17, 2012 Advertisement (gone after registration) Hello there, Could you please explain me that what kind of material was used at LTM Leicas Upper Body and how it is finished ? Is there a technical article or report on how it is electroplated and by which formula and at which chemical bath condition ? I read years ago brass and chrome finish but I could not confirm it at internet. And Is Brass alloy important to get same finish or is there an interlayer between brass and electroplating. I am interested in grey finish but all black finish details are welcome also ? Mustafa Umut Sarac Istanbul Quote Link to post Share on other sites More sharing options...
Advertisement Posted September 17, 2012 Posted September 17, 2012 Hi Mustafa Umut Sarac, Take a look here LTM Camera Finish Technology. I'm sure you'll find what you were looking for!
lars_bergquist Posted September 17, 2012 Share #2 Posted September 17, 2012 Both the top cover (including the separate rangefinder housings of models II to IIIb, and the housing under the shutter dial of all Leica I and Standards) and the baseplates were of drawn brass. Black finishes were a shiny black etching ground lacquer, probably applied directly without any ground. How Leitz prepared the brass for the chromium plating I don't know; general practice in the surface treatment business seems to be a thin preparatory layer of copper. Early chroming from about 1933 or so seems to be shinier than later practice. The quality of the chrome deteriorated during the last years of World War II and the early peace years, as Germany had a bad shortage of chromium, which is of course a strategic material. This was the reason behind the dark-grey cameras from the war years. The old man from the Bad Old Days Quote Link to post Share on other sites More sharing options...
Mustafa Umut Sarac Posted September 17, 2012 Author Share #3 Posted September 17, 2012 LTM Body Finish Technology writer :Summicron1 After world war ii british intelligence -- james bond? -- visited Leica and wrote a complete description in some detail of the manufacturing process underway. It includes a description of how they got that specific finish which, I have to say, I do not think they successfully duplicate today. You can find the whole thing here: LEITZ INVESTIGATED BY BRITISH INTELLIGENCE 1946 Specifics of the satin finish are: 25. The satin-chrome finish on external metal parts was obtained by the following process:- 26. Sandblast, hot cleaner without current, cold cleaner with current, warm rinse, followed by cold rinse, hydrochloric dip, copper flash, cold rinse, sulphuric dip, cold rinse, bright nickel-plate, warm rinse, hydrochloric dip, bright chrome, drag-out rinse, cold rinse, hot rinse, and dry. 27. All articles were jigged on racks and the racks were screened to obviate side-throw. 28. The bright nickel tank was approximately 6' x 2' x 21/2', six depolarised anodes being employed. The volt-meter and ammeter on the resistance control board were all moving coil pattern and the tank was worked at 2 volts, 25 amps. No agitation of the electrolite was employed. 29. The chrome tank was approximately 4' x 2' x 21/2', twenty- eight strip anti-monial lead anodes being employed. Moving coil volt and ammeters were also fitted in the resistance board and the tank was worked at 51/2 volts, 300 amps. 30. It was particularly noted that the time allowed for a satisfactory chrome deposit was exactly three minutes. All the plating equipment was spotlessly clean. Quote Link to post Share on other sites More sharing options...
Mustafa Umut Sarac Posted September 17, 2012 Author Share #4 Posted September 17, 2012 As you follow linked my APUG thread , Leica uses copper , nickel and chrome electroplating in order. Someone claimed nickel interlayer changes the top Chromium layers appearance and color. Is it possible ? Mustafa Umut Sarac Istanbul Quote Link to post Share on other sites More sharing options...
jc_braconi Posted September 17, 2012 Share #5 Posted September 17, 2012 As you follow linked my APUG thread , Leica uses copper , nickel and chrome electroplating in order. Someone claimed nickel interlayer changes the top Chromium layers appearance and color. Is it possible ? Mustafa Umut Sarac Istanbul Yes Quote Link to post Share on other sites More sharing options...
Mustafa Umut Sarac Posted September 17, 2012 Author Share #6 Posted September 17, 2012 twenty-eight strip anti-monial lead anodes being employed. Thank you Moderator. I have another question , what is the meaning , explanation about above listed sentence which taken from attached intelligence report ? Does anyone have an idea ? And is there any other information on micron thickness of each of three layer ? Mustafa Umut Sarac Istanbul Quote Link to post Share on other sites More sharing options...
Twotone Posted September 17, 2012 Share #7 Posted September 17, 2012 (edited) Advertisement (gone after registration) twenty-eight strip anti-monial lead anodes being employed. Thank you Moderator. I have another question , what is the meaning , explanation about above listed sentence which taken from attached intelligence report ? Does anyone have an idea ? And is there any other information on micron thickness of each of three layer ? Mustafa Umut Sarac Istanbul An anode is usually used to do something to the water or protect something else. For example in plumbing inside a tank, stainless steel or similar, a sacrificial anode is used to protect the steel i.e the anode rots before the tank. Electrolytic corrosion takes place inside the tank when dissimilar metals are in contact in water/liquid. The anode will be made of metal lower down the electrolytic scale. For example gold and platinum are at the top end of the scale and the likes of lead and tin are at the bottom. Antimony is a lead alloy BTW used in making (lead) solder. http://www.dtsfe.com/faq/pdf/electolytic%20corrosion.pdf http://www.hmsmetalcorporation.com/lead_alloy.htm Edited September 17, 2012 by Twotone Quote Link to post Share on other sites More sharing options...
lars_bergquist Posted September 18, 2012 Share #8 Posted September 18, 2012 Anodes and cathodes are electrodes of different polaritgies: cathode negative (e.g. emitting electrons) and the anode is the positive one. All forms of electrolytic surface finishing use these electrodes, with the workpiece as a cathode. The old man from the Selenium Age Quote Link to post Share on other sites More sharing options...
jc_braconi Posted September 18, 2012 Share #9 Posted September 18, 2012 Anodes and cathodes are electrodes of different polaritgies: cathode negative (e.g. emitting electrons) and the anode is the positive one. All forms of electrolytic surface finishing use these electrodes, with the workpiece as a cathode. The old man from the Selenium Age What I have taken at school for remembering were Anode an n for negative and an o for oxygen. Acathode by definition now is positive an h for hydrogen. About galvanoplasty you can find a lot on wikipedia so I dont want to charge the post Quote Link to post Share on other sites More sharing options...
k_g_wolf ✝ Posted September 22, 2012 Share #10 Posted September 22, 2012 It would be very much easier, JC, if you could write down here everyting you know .... Best GEORG Quote Link to post Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.