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#1 - 2008-2-12 23:06
Heifetz
哪个内置光罩并不理想，太小，太短，一般情况可以应付。。。。看看这个
 [attach]35167[/attach] [attach]35168[/attach] [attach]35169[/attach] [attach]35170[/attach]  附件: 您所在的用户组无法下载或查看附件
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#2 - 2008-2-13 06:32
Heifetz
这是整个过程中最难的，打孔的角度！两个报废的扳手都是出了不准确的问题。
  两个精密的小螺丝是从对焦环从内往外加上螺丝固定剂将扳手紧紧的固定在对焦环上的。决定是100％的可靠 |
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#3 - 2008-2-13 17:23
Heifetz
金属表面工艺我不懂
 我找了点质料，但，都是英文的。。。 这种工艺有很多颜色。见图。。。[attach]35225[/attach] [attach]35226[/attach] [attach]35228[/attach] [attach]35229[/attach] Anodized aluminum Aluminum alloys are anodized to increase corrosion resistance, to increase surface hardness, and to allow dyeing (coloring), improved lubrication, or improved adhesion. When exposed to air at room temperature, or any another gas containing oxygen, pure aluminum self-passivates by forming a surface layer of amorphous aluminum oxide 2 to 3 nm thick which provides very effective protection against corrosion. Aluminum alloys typically form a thicker oxide layer, 5-15 nm thick, but tend to be more susceptible to corrosion. Aluminum alloy parts are anodized to greatly increase the thickness of this layer for corrosion resistance. Generally, corrosion resistance is significantly decreased by alloying elements or impurities such as copper, iron, and silicon.,[4] so 2000, 4000, and 6000-series alloys tend to be most susceptible. Most aluminum aircraft parts, architectural materials, and consumer products are anodized. Anodized aluminum can be found on mp3 players, flashlights, cookware, cameras, sporting goods, window frames, roofs, in electrolytic capacitors, and on many other products both for corrosion resistance and the ability to retain dye. Although anodizing only has moderate wear resistance, the deeper pores can better retain a lubricating film than a smooth surface would. For example, the cylinders of a modern BMW aluminum V8 cylinders have no loose liner: instead, the walls are hard anodized. This complicates a reboring operation (although not common, given the longevity of modern engines due to improved lubricants), as the hard coating must be restored if the block is rebored. (Earlier liner-free aluminum block designs use specific aluminum alloys, with softer components chemically etched away to expose the harder portions of the mixed crystal structure.) Anodized coatings have a much lower thermal conductivity and coefficient of linear expansion than aluminum. As a result, the coating will crack if exposed to the "thermal stress" of a 60°C change from the anodizing temperature, or in general any temperature gradient caused by caused by a rapid change in ambient temperature, although aluminum is less susceptible to this, due to high thermal conductivity. The coating can crack, but it will not peel. The melting point of aluminum oxide is 2050°C, much higher than pure aluminum's 658°C.(This can make welding more difficult.) When aluminum is oxidized, it doubles in volume. So in a typical aluminum anodization process, the aluminum oxide grows down into the surface, and at the same time grows an equal distance out from the surface. So anodizing will increase the part dimensions on each surface by half of the oxide thickness. For example a coating that is (2 μm) thick, will increase the part dimensions by (1 μm) per surface. If the part is anodized on all sides, then all linear dimensions will increase by the oxide thickness. Process Before being anodized, wrought alloys are cleaned in either a hot soak cleaner or in a solvent bath and may be etched in sodium hydroxide (normally with added sodium gluconate), ammonium bifluoride or brightened in a mix of acids. Cast alloys are normally best just cleaned due to the presence of intermetallic substances unless they are a high purity alloy such as LM0. The anodized aluminum layer is grown by passing a direct current through an electrolytic solution, with the aluminum object serving as the anode (the positive electrode). The current releases hydrogen at the cathode (the negative electrode) and oxygen at the surface of the aluminum anode, creating a build-up of aluminum oxide. Alternating current and pulsed current is also possible but rarely used. The voltage required by various solutions may range from 1 to 300 V DC, although most fall in the range of 15 to 21 V. Higher voltages are typically required for thicker coatings formed in sulfuric and organic acid. The anodizing current varies with the area of aluminum being anodized, and typically ranges from 0.3 to 3 amperes of current per square decimeter (15.5 square inches). Aluminum anodizing is usually performed in an acid solution which slowly dissolves the aluminum oxide. The acid action is balanced with the oxidation rate to form a coating with microscopic pores, 10-150 nm in diameter.These pores are what allows the electrolyte solution and current to reach the aluminium substrate and continue growing the coating to greater thickness beyond what is produced by autopassivation.[6] However, these same pores will later permit air or water to reach the substrate and initiate corrosion if not sealed. They are often filled with colored dyes and/or corrosion inhibitors before sealing. Because the dye is only superficial, the underlying oxide may continue to provide corrosion protection even if minor wear and scratches may break through the dyed layer. Conditions such as electrolyte concentration, acidity, solution temperature, and current must be controlled to allow the formation of a consistent oxide layer. Harder, thicker films tend to be produced by more dilute solutions at lower temperatures with higher voltages and currents. The film thickness can range from under 0.5 micrometres for bright decorative work up to 150 micrometers for architectural applications. The most widely used anodizing specification, MIL-A-8625, defines three types of aluminum anodization. Type I is Chromic Acid Anodization, Type II is Sulphuric Acid Anodization and Type III is sulphuric acid hardcoat anodization. Other anodizing specifications include MIL-A-63576, AMS 2469, AMS 2470, AMS 2471, AMS 2472, AMS 2482, ASTM B580, ASTM D3933, ISO 10074 and BS 5599. AMS 2468 is obsolete. None of these specifications define a detailed process or chemistry, but rather a set of tests and quality assurance measures which the anodized product must meet. BS 1615 provides guidance in the selection of alloys for anodizing. For British defence work, a detailed chromic and sulfuric anodizing processes are described by DEF STAN 03-24/3 and DEF STAN 03-25/3 respectively. QUOTE: 原帖由 macg4 于 2008-2-13 15:28 发表   Heifetz： 镀黑是用得什么工艺？磷化吗？ 手工真是没得说，高仿！ [ 本帖最后由 Heifetz 于 2008-2-13 17:53 编辑 ] 附件: 您所在的用户组无法下载或查看附件
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#4 - 2008-2-13 17:52
Heifetz
实际上，拆镜头，用螺丝，打孔，套罗口是我走了条复杂的弯路，用了很多时间和精力。。。
 今早突然想起有种工业双组合金属胶完全可以将扳手牢固的粘贴在调焦环上。重要的是1，扳手的材料最好是和调焦环一样，2，粘贴部的表面，弧度要处理的特别准确。最好是用一段内直径和调焦环外直径相同的铝管。这样你只加工外形就容易多了。。。 QUOTE: 原帖由 雨齐 于 2008-2-13 16:22 发表 这是怎么黏上去的？一直想DIY一个扳手装福伦达35/1.7上 |
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#5 - 2008-2-13 20:30
carnotaur
俺也是超喜欢这只标头，俺的第一支徕卡镜头。
当时选这只标头倒没考虑入门的问题，主要是喜欢没对焦扳手，外形上更对称。 片子很能代表MTF图显示的性格，像场平坦，反差、锐度、散景都是恰到好处，正是俺喜欢的。 后来用习惯八枚玉，发现对焦扳手严重方便，主要是可以预先做粗略的对焦，拍过几个卷之后几乎可以一拧就对焦到想要的位置，然后才靠取景器叠影精细对焦，极大提高抓拍速度。 结果现在用这只现行版标头倒不习惯了，举起相机前总不知道大致的焦点在哪。 LZ要是再做上个无限远锁定就超级牛叉了，那个也是非常实用的功能。 |
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#6 - 2008-2-13 23:56
阿唐
楼主只要把这支50／2换成前一个版本就无须这番功夫了，因为之前的那一版本50／2自带对焦扳手的。
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#7 - 2008-7-31 21:00
Alan
楼主敢想敢做
佩服啊佩服  |
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#8 - 2008-8-7 18:10
卡徕
佩服啊佩服
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#9 - 2008-8-22 23:14
Alan
楼主是否考虑一下量产?
呵呵 |
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