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[技术] 螺旋桨制作

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发表于 2010-12-19 04:56:13 | 显示全部楼层 |阅读模式
螺旋桨制作

从Octura金属螺旋桨都是投铍铜。 其他材料可用于制造不锈钢,例如螺旋桨,螺旋桨但绝大多数金属铍铜。 前一个金属螺旋桨可以使用,它需要磨和平衡。
Metal propellers from Octura are cast in beryllium copper. Other materials are used to make propellers, for example stainless steel, but the vast majority of metal propellers are beryllium copper. Before a metal propeller can be used, it needs to be sharpened and balanced.

Surface piercing propeller. Thrust is produced by the concave face, and you must not modify the shape of this face when preparing the propeller or you risk altering the propeller's characteristics. Material is removed evenly from the convex face to sharpen and balance.
I often get asked if I sell ready sharpened propellers, and my answer is always a firm "no". I hate sharpening propellers, and am only prepared to do my own!
It is possible to buy propellers ready sharpened and balanced for you. However, in my experience propeller preparation takes a long time, perhaps as much as two or three hours per propeller. People who sell sharpened and balanced propellers usually do the bare minimum to make a propeller usable, but "usable" is not the same as "perfect". We're after perfection, or as near as it's possible to get, and this means doing it yourself. This is not meant to denigrate those vendors who sell propellers and charge for sharpening and balancing. The blunt economic reality is that time is money, and if you want a near-perfect propeller, then it's going to cost a lot more than one that is merely usable. Ask yourself what price you would put on three hours of your time?
So, what is the difference between a "usable" propeller, and a near-perfect propeller? The difference can be remarkable. The propeller determines motor rpm, run time and speed, and a usable propeller will be down on all three. If you want to win, you need to have decent propellers for your boats - it's that simple.
A propeller with razor sharp, thinned blades does not waste as much energy on each rotation. Thinned, sharp blades enter the water with less impact and therefore create less spray, with more of the motor energy being converted to useful thrust.
 楼主| 发表于 2010-12-19 04:56:24 | 显示全部楼层
Safety
Before going any further, it is imperative that before you start working with beryllium copper, you fully understand the health and safety aspects of this material. Beryllium copper ("BeCu") is toxic, and in its solid form presents no great hazard. The danger lies in the dust that is produced when BeCu is worked or machined. BeCu dust causes serious lung damage and is carcinogenic. For this reason, it is strongly recommended you do not use power tools to prepare BeCu propellers, as the last thing you want in your workshop is a fine mist of particles in the air that you will end up breathing in, and that will persist as dust for months or years.
I keep a seperate set of files for propeller preparation, and do most of the work on my propellers using various grades of wet-and-dry abrasive paper used wet, as the water flushes the wet-and-dry clear of dust and also traps the dust in the water. Also, files tend to clog easily when working BeCu, and can cause deep scratches. If I can avoid using a file, I do. However, to remove a large amount of material from the blades of a propeller you need to use a file, swapping to wet-and-dry for final finishing and balancing.
Preparation
The steps required to take a propeller from the new, as-cast state to ready-to-race are simple. First, you need to thin the blades by removing material from the convex face (see the diagram to explain convex and concave faces) using a file and wet-and-dry abrasive paper used wet. Some propellers have blades that are nearly the same weight as-cast, others can be radically different, perhaps even with one blade visibly thicker than the other. You may wish to check the initial as-cast balance to see which blade is going to need more material removed as you progress.
prop_rear_view.jpg
Rear view of a surface drive propeller.

prop_sections.jpg

Propeller section "A" as shown above. In this diagram, 1 is as-cast. 2 is the sort of shape you can buy, and is usable but far from optimal. 3 is the kind of profile we're looking for; thinnned and razor sharp, this propeller will be a screamer. A razor sharp propeller with thinned blades has a lower impact force as the blade enters the water on each rotation, which reduces spray and increases propeller efficiency.
 楼主| 发表于 2010-12-19 04:56:36 | 显示全部楼层
The key to producing a good propeller is to work over the entire face of each blade. What you are seeking to achieve is a propeller with thin blades, razor sharp edges and which is well balanced. This last point brings us onto balancers.
prop_prep.jpg

The trailing edges must be kept sharp to allow water to shed cleanly from the blades. Do not alter the concave face of the propeller - you risk reprofiling the propeller and altering the pitch or cupping.

prop_cupping.jpg

Cupping on the trailing edge of the propeller blade alters the shape of the propeller's thrust cone. More cupping results in a narrower thrust cone which gives better acceleration and less vertical lift - the propeller "grabs" the water harder, producing much better acceleration from rest and out of corners.
 楼主| 发表于 2010-12-19 04:58:39 | 显示全部楼层
Balancers
The only type of balancer that is sensitive enough to balance small propellers is the magnetic type. A magnetic balancer consists of a shaft which is suspended between two magnets. The propeller is threaded over the shaft, and when mounted between the magnets, the heavy blade will drop to the bottom.
There is only one problem with the magnetic balancer: unless the balancer is a quality item, it simply will not be accurate. The most important part of the balancer is the shaft, which must be dead straight and have ends which are precision ground. If the shaft is even slightly bent or curved, or if the tips are not machined or ground concentric to the shaft OD, then the shaft itself will be way, way out of balance and it will not accurately tell the balance state of a propeller.
Surface Finish
There is a myth that a highly polished propeller works better - it doesn't. Indeed, the reverse seems to be the case, that a mirror finish actually degrades performance. My personal preference is to finish a propeller with 600 grit wet-and-dry paper, leaving a satin finish. However, if you feel the need for a highly polished propeller, go ahead - but rememeber that BeCu tarnishes over time, and a mirror finish won't last once you get it wet.
Propeller Modification
This article about propeller preparation assumes you want to use a propeller as designed by the manufacturer, and for the vast majority of people (myself included) a standard propeller works fine. It is, however, possible to modify the size and shape of a propeller to achieve various effects. For example, increasing or decreasing the cupping to change the amount of lift generated or to increase motor rpm, or altering the blade area and/or diameter to reduce motor loading, or to fine tune boat handling.
Changing the shape of a propeller is a techique more often used in IC boating where the small, high-revving piston engines used have a very narrow power band. Subtly altering the pitch or cupping can allow an IC boat to run "on the pipe", or in the rpm range where the exhaust pipe is working in its tuned range. Electric motors produce maximum torque from zero rpm, and do not need this kind of propeller tuning, other than to reduce current draw or to alter boat handling.
Modifying propellers is a bit of a black art, and beyond the scope of this article. To achieve any kind of successful modification to a stock propeller requires plenty of time for testing, plenty of money to buy propellers, a comprehensive knowledge of propeller theory and a selection of specialist tools like a pitch gauge and propeller anvil. For most of us, a stock propeller finished to a high standard will give perfectly acceptable results.
Conclusion
Metal propellers require a fair amount of work to get the best results, and time spent learning how to correctly prepare a metal prop will bring rewards in the shape of a faster boat that runs with a lower current drain and higher motor rpm.
However, if all this mucking about with files, balancers and toxic metals seems like a lot of hard work, you can always opt for carbon fibre propellers. These work very well indeed, and require no preparation at all.
发表于 2011-3-29 20:47:12 | 显示全部楼层
看不懂啊,有没有翻译?
发表于 2011-5-7 14:51:10 | 显示全部楼层
就是,就是
发表于 2011-5-10 18:58:36 | 显示全部楼层
从金属螺旋桨是投上Octura铍铜合金。其他材料可用于制造螺旋推进器,例如不锈钢,但绝大多数的金属螺旋桨是铍铜合金。前一个金属螺旋桨可以被使用,它需要被磨与平衡。


螺旋桨表面刺穿。产生的推力是凹脸,你们必须修改这个脸的形状或你当准备改变螺旋桨桨的风险特征。资料被均匀地自凸的脸锐化和平衡。

我经常被问到我卖,我准备好了加剧了螺旋桨坚定的回答总是“不”。我讨厌削尖的推进器、现在我只能做好准备,我自己!

它是可能买到螺旋桨磨和平衡,你准备好了。然而,在我的经验里,螺旋桨准备要很长时间,可能多达两三个小时每桨。那些出售磨和平衡的螺旋桨通常最低限度,使一个推进器可用,但“可用”是不一样的“完美”。我们一直在寻找完美,或者接近于它是可能弄到,这就意味着做它你自己。这不是说要诋毁那些供应商出售螺旋桨和费用主要是为了削尖和平衡。直率的经济的现实情况是,时间就是金钱。如果你想要一个完美的推进器,那么它将花费很多多于一个,仅仅是可用的。问问自己什么价格你就放3个小时的时间吗?

所以,有什么区别"可以使用的"螺旋桨推进器,近乎完美吗?能够显著的差异。决定了电机转速,螺旋桨运行时间与速度、一个可用的螺旋桨会缩小了所有三个。如果你想获得胜利,你需要为你的船有象样的螺旋桨-它是那么简单。

螺旋桨叶片用剃刀锋利,变薄不浪费多少能源在每旋转。薄,锋利的刀片入水冲击,因此较少产生较少的喷雾,更多的电机能量被转换到有用的推力。
发表于 2011-5-10 19:02:31 | 显示全部楼层
去之前,任何进一步的,这一点是非常必要的,在你开始工作之前与铍铜合金,你充分了解健康和安全方面的资料。铍铜合金(“BeCu”)是有毒的,并对其在固体形态呈现不危害很大。危险在于在尘土中了,这是产生时的结构和工作原理,BeCu或加工。BeCu粉尘造成了严重的肺损伤和是致癌的。因为这个原因,它是被强烈建议你不要使用电动工具准备BeCu螺旋桨、为你最不想要的事情在您的工作室是一个细雾中粒子的空气,最终你会呼吸,这将持续数月或数年的灰尘。

我保持一个单独的文件集合为推进器的准备,以及做大部分工作在我的螺旋桨使用各种等级的wet-and-dry磨料用纸湿,当水冲洗wet-and-dry清晰的灰尘和也陷阱的灰尘在水里。同时,文件时很容易倾向于堵塞,又能使工作BeCu深划痕。如果我能避免使用了一个文件,我做的事。然而,消除了大量的资料,从叶片的螺旋桨你需要使用一个文件,转向wet-and-dry为最终精加工和平衡。

制备

所需的步骤把螺旋桨从新的、铸态状态到ready-to-race都很简单。首先,你要薄刀片除去,从材料的凸的脸(见图表来解释凸和凹脸)用一个文件和wet-and-dry磨料用纸弄湿了。有一些螺旋桨叶片,几乎是同样重量的铸态,也有的可能是完全不同的,甚至用一把刀片明显较厚比其它的。你可能想去看看那最初的铸态平衡,看看哪个叶片会需要更多的资料删除你的进步。

19.18下载(KB)


2011-3-30 03:56

后面观看一个表面的驱动螺旋桨。


下载(227 KB)


2011-3-30 03:56


螺旋桨节" A "如上所示。在这个图中,一条是铸态。2是先天的形状,你就可以买到,并可用但远非最佳。3种,是我们正在寻找的轮廓;thinnned和锋利,该螺旋桨将喊叫。一个锋利的螺旋桨桨叶与较低的影响变薄叶片力,入水时,在每一个旋转,从而降低了喷雾和增加螺旋桨的效率。
发表于 2011-5-10 19:04:18 | 显示全部楼层
均衡器

唯一的一种平衡,平衡是不够灵敏,小螺旋桨是磁性的类型。一个磁性的平衡器是由一个轴悬在两个磁体。螺旋桨是螺纹在轴上,而当安装之间的磁石的著磁,沉重的刀片将降至底部。

只有一个问题:除非磁平衡平衡器是一种高质量的项目,那是绝对不是很准确。最重要的部分是轴的平衡器,必须直直地和有目标精密研磨。如果轴甚至稍微弯曲或弯曲,或者如果小费不是加工或地面同心轴外径尺寸,然后轴自身将方式,出路的平衡,也不能准确说出平衡态的推进器。

表面光洁度

有一个神话说高度抛光的螺旋桨工作得更好-它没有。事实上,相反的似乎是怎样,那镜面光洁度实际上会降低网路的效能。我个人偏好来完成一个推进器在600砂砾wet-and-dry纸,留下一个缎完成。然而,如果你觉得需要用高度抛光的推进器,去吧——但会记得,随著时间的推移,使BeCu镜面光洁度不会持续一旦你弄湿了。

螺旋桨改性

这篇关于螺旋桨的准备是假设你想要使用一种螺旋桨是设计的生产厂家,对于绝大多数人(包括我在内)一标准螺旋桨运转得很好。然而,它是可能的修改大小与形状的螺旋桨来实现各种效果。例如,增加或减少的数额火罐改变人生的生成,或是增加电机转速,或改变叶片面积和/或直径减少电机负载,或以调整船搬运。

改变其形状的螺旋桨是一个技术更常用于IC划船的地方小,high-revving活塞式发动机使用的有一种非常狭窄的权力的乐队。微妙的改变场上火罐可以让一个集成电路或船在管上的“跑”,或者在每分钟转速范围的地方是在它的排气管调谐范围。工作电机产生最大转矩转速,从零,并且不需要这种推进器微调,其他除了减少当前配置或改变船的搬运。

修改螺旋桨是有点黑艺术,超出这篇文章的范围。任何一种成功实现螺旋桨需要修改一个股票有充裕的时间进行了测试,足够的钱去买的推进器、综合知识的螺旋桨理论和一选择的专业工具,如球场的厚度和螺旋桨铁砧。对我们大多数人来说,完成了对股票螺旋桨高标准会给完全可以接受的结果。

结论

金属螺旋桨需要相当多的工作要得到最好的结果,和花时间学习如何正确准备一个金属的道具会带来奖励的形式运行提供了更快的船,小的电流排水和更高的电机转速。

然而,这一切是否都无所事事和档案,均衡器和有毒金属似乎有许多艰苦的工作,你一定都能选择的碳纤维螺旋桨。这些作品的时候真的很好,不需要准备。
发表于 2014-9-29 06:15:34 | 显示全部楼层
看看,还可以哦!
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