Titanium Leica notes
The titanium in the "Titanium Leica M6" is merely a thin plating applied to plain old brass. Yes, you read correctly - the titanium is merely plated on as a thin outside layer, it is not solid titanium alloy.
You may have read that this Ti coating helps make the Titanium Ms scratch-proof. Unfortunately this is not the case. There are many different types of Titanium alloy, and the most useful versions are chosen for their strength and ease to work with, not because they are resistant to physical wear or scratching.
Tom Abrahamsson fills us in on the details:
The Titanium M6 is a bit of a misnomer. The top and base plates are made from brass and Titanium (nitride) coated. The lenses are the same as the chrome lenses as they have the brass barrels. This kind of defeats the purpose of using Titanium, which in the normal alloyed form is light and strong. In the Leica case, it will wear off and the brass will show up underneath! I know this from experience as my M6 Titanium is now a mixture of Titanium and brass colouring, as well as somewhat dented in one corner. One of these days I will take it apart and have it painted black! It is a reasonably hardwearing surface though, it took a multitude of film and the assistance of a car-door to give the camera it's true patina.
If you are really interested in the chemistry behind Ti plating and vapour deposition, see <LUG - v25/msg04429.html> by a qualified metallurgist in July 2003. His best guess is that the Ti plating is actually Ti Nitride. FWIW!
Why not use solid Ti?
So why not use real, solid, honest-to-goodness titanium alloy? In May 2003 Mark Wahlster sent me the following remarks:
As far as CNC milling [a Leica M6/7/MP] top from a solid Ti block, yes it would be possible but I assure you the failure rate, combined with the terrific cost of hand finishing the part to a level that could be merely painted, let alone left bare, would double at least the cost of any Leica camera with the parts made this way.
Tooling costs alone would be in the range of $50.00, even with a volume purchase, as Titanium is very, very hard on cutting tools. Its "sticky" properties lead to a very high tool breakage rate and the level of CNC machine required to do this type of milling on a production basis can run into the $500K range.
[To close with an example, a custom knife-handle I made from solid Ti in the early 1990s …] took the life of three drill bits (all very high quality) and two counter sinks. If I remember correctly, it took nearly four hours to do the drilling on my mill and the one time I made a number at a time the failure rate was near 30% - either the hole would burn out or the material would grab the cutter and snap it causing a scar next to the hole.
Which confirms earlier remarks by Bob Fleischman in May 2002:
As far as titanium goes, it's not a very workable material. To Ti- plate a body shell, as Leica does, is one thing; to attempt to machine a part out of solid Ti is something else.
I found this out years ago in the Air Force. The F-105 had titanium shells inside the engine exhaust nozzle. When the rep from Republic Aircraft told me what it took to drill each hole in one of these panels, I realized this is not a material you use unless nothing else will work. It takes 18 drill bits per hole. Since Leicas don't usually have to stand up to jet afterburner temps, there's little reason for Ti.
Dancing with the devil - working with Ti
In Oct 2001, Richard Ilomaki noted the following properties of Ti which make it such a bear to work with:
(1) Titanium is needed only where other materials will not perform, such as F1 racing engine connecting rods that MUST be as light as possible to withstand the reciprocating nature of the movements with minimum inertia. The same goes for valves for the engines.
Jet fighters -F18- use Ti structural members, part of the reason they cost $100 million a pop. Casting Ti is viciously expensive as it is a VERY combustible metal until a micro-thin coating of oxide is built up. Freshly ground Ti in a nitrogen blanket would ignite spontaneously if the Nitrogen blanket were blown away.
It must be cast in a vacuum furnace and machined under an inert gas or liquid blanket. Dust from Ti machining is highly explosive and preventing explosions adds to the cost of machining.
Any engineer who uses Ti where another metal or alloy will do is off base.
(2) Following on from above, the reason shutter assemblies are made of Ti is to maintain the strength needed to allow 1/8000 sec shutters. The acceleration and deceleration called for to move through a 24mm distance twice in less than 1/10 000 of a sec. is phenomenal: equivalent to many Gs of acceleration. Ordinary steel or Aluminum sheets would lose shape and jam, or if they were strong enough, would be too heavy and just not move fast enough.
Ti is used extensively for artificial joints such as knees and hips as the inertness is critical in body fluids. A CNC machine needed to machine Ti costs over $1 million, so the cost per unit must be VERY high to pay for this on low volume runs. We already complain about the cost of Leicas vs real performance.
(3) Ti does have certain corrosion resistant properties but these do not apply in ordinary atmospheres: highly oxidizing gases such as Chlorine Dioxide call for Ti.
(4) Using the word "Titanium" in marketing is magic. It makes people think they are sharing needed technology with spacecraft or trendy F1 Ferrari or Mercedes Benz engines.
The best way to scratch-proof a Leica is to provide an adhesive plastic sheet on the top, such as the one on the bottom of a new Leica. It could be applied before a trip or threatening shooting session, then peeled off.
The answer to your question is that it would cost tens of thousands of dollars and would be no better than a run of the mill current M6. It would, however, be a real status symbol for the "more money than brains" gang.
Back to earth…
All this is well and good, but methinks the engineer in these blokes doth protest too much. First of all, they appear to be talking about exotic aerospace-grade Ti alloys, rather than more benign consumer varieties. Secondly, they all forget to mention that the major reason Ti wasn't used extensively in the past was because it was classified a "Strategic Material", and as such, its use in large quantities for civilian applications was "seriously discouraged".
However, with the end of the cold war and plentiful supplies available from Australian or the ex-Soviet Union, Ti alloys are now popping up everywhere: Golf clubs & balls (eg. Spalding), wristwatches (eg. Seiko and Tag Heuer Kirium Ti5 Titanium watches), spectacle and sunglass frames (Oakely X metal frames) and even jewelry or camping forks & spoons!
Also, the "way too hard to machine" excuse may be overstating things as well, as remarked by: Steve Belden
Tooling technology has advanced some [… in recent years.] It is no longer that difficult to machine Titanium. I am a machinist by trade and have made myself some camera accessories out of leftover bits and pieces of Titanium from jobs. I agree that using it for a camera body is certainly overkill. The only reason I use it is because it impresses the hell out of people when you tell them your flash bracket is made of titanium. There may be a case for using it to make lens barrels as I believe it has a similar expansion coefficient as glass.
Practically, Leica don't make body shells out of solid titanium as (1) they already have a huge investment in centrifugal zinc alloy casting and CNC machines (the latter is actually out-sourced to Cloessner GmbhH, but you get the idea); (2) machining and finishing zinc alloy or brass is much simpler than working with titanium alloy and (3) would the improved strength, temperature and corrosion resistance really be that much of a benefit?…
Sheik Saud Ben Mohammed Ben Ali Al-Thani's solid Ti M7
If you throw enough money at a problem then a solution will eventually present itself…
In Aug 2003, Leica Fotographie International Magazine (06/2003) profiled a special Ti Leica M7, made as a one-off for Sheik Al-Thani:
A special Leica-fan had a very special request. He wished to have an M7 constructed entirely out of titanium. The idea of his Excellency Sheik Saud Ben Mohammed Ben Ali Al-Thani confronted Leica with a very special challenge. The result is not only excitingly beautiful but also as solid as a rock.
Apparently it was CNC milled from solid Ti blanks and the final camera did not have any kind of vulcanite or leatherette covering. On the last page of the article, the good Sheik claimed the camera was for actual use rather than just display. Well if you've got that kind of money, then why not!
50th Anniversary Leica - M7 Ti
To commemorate the 50th anniversary of Leica M production, in June 2004 Leica announced the release of 500 solid Titanium M7s with accompanying lenses at Photokina '04. See <Photo.net: #008UtH>.
In June 2004 "Lucien" noted:
50 ex. M7 with 28/2, 50/1,4 (new) and 90/2, made of solid titanium (not plated) = € 20 000 Euros. (sold out)
500 ex. M7 with 50/1,4 new, both also made of titanium = € 10 000 Euros.
In August 2005 Aubrey Whinney added:
The implication is that the 50th Anniversary M7 Ti has its body covered wih carbon fibre rather than leatherette.
When was the last time you ran your thumbnail over carbon fibre AND left an impression?
I own an M7 50th Ti and am in full agreement with Leica that the covering is saddle leather. Beautiful.
P.S. Neckstrap is the same material.
FWIW the existence of these commemorative models should put to rest the notion that solid Titanium camera bodies cannot be made :?)