As a disclaimer, this story contains content surrounding Covid-19. I completely understand that not everyone is in a place to read about this very real issue.

作为免责声明，此故事包含有关Covid-19的内容。 我完全理解，并不是每个人都可以阅读这个非常实际的问题。

I recently started working in the software development and consulting industry, so recently in fact that I’ve spent more time working from home in our current situation than I have spent at the offices. But before that, I was in the process of becoming a professional student of chemical engineering and the topic of my Master’s thesis was focused on making specialised materials for 3D printing. Yes, that's right, I came in to “work” on campus every day to drink coffee and play around with 3D printers.

我最近开始从事软件开发和咨询行业的工作，因此实际上，最近我比在办公室花费更多的时间在目前的情况下在家工作。 但是在此之前，我正在成为化学工程专业的学生，​​我硕士论文的主题是致力于制造3D打印的专用材料。 是的，没错，我每天都在校园里“上班”喝咖啡，和3D打印机一起玩。

While there is a little bit more to it than that, suffice it to say that I enjoyed 3D printing enough to change my topic 1 year deep into a 2 year degree. And by the way, we are now in year 3, and I don’t know if “enjoy” is a suitable term I can use any more. It has become a labour of love to continue my research, and while I still use my printer as a trinket collector, I haven’t printed anything meaningless since March 16th. Pause for dramatic effect while I divert away from the story to explain a little about 3D printers.

虽然还有很多，但可以肯定地说我很享受3D打印，足以将我的主题从1年更改为2年。 顺便说一句，我们现在已经进入三年级了，我不知道“享受”是否是我可以再使用的合适术语。 继续进行研究已经成为我热爱的工作，尽管我仍将打印机用作装饰品的收集者，但自3月16日以来，我从未进行过任何毫无意义的印刷。 暂停播放戏剧性的效果，而我将注意力从故事中移开，以解释一些有关3D打印机的信息。

切线数1。 (Tangent number 1.)

3D printing is a very loose term, and it actually covers a huge array of processing and manufacturing techniques ranging from hobbyist and prototyping machines that use plastic strand or resin, to metal laser-melting machines that make parts for aeroplanes and BMWs, but the one that I’d like to talk about is known as fused deposition modelling (FDM, the patented name) or as fused filament fabrication (FFF, the fffreely available name). In the simplest terms, FDM is a process of melting some plastic stock material and then placing it down in specific patterns, one layer at a time, until the final print takes the wanted shape. Here’s a slightly more complicated version, but in picture format.

3D打印是一个非常宽松的术语，它实际上涵盖了广泛的加工和制造技术，从使用塑料线或树脂的爱好者和原型制作机到制造飞机和宝马零件的金属激光熔化机，仅此而已。我想谈论的就是熔融沉积建模(FDM，专利名称)或熔融长丝制造(FFF，ffffly可用的名称)。 用最简单的术语来说，FDM是将一些塑料原料熔化，然后以特定的图案(一次一次)放置到最终的印刷品呈所需形状的过程。 这是一个稍微复杂些的版本，但采用图片格式。

切线数2。 (Tangent number 2.)

FDM (and 3D printing in general) produces parts that can be stronger* and use less* material than a conventionally produced part thanks to the nature of additive manufacturing, but both of these have some hidden terms and conditions. I used another term for 3D printing there (Additive Manufacturing, AM). In its simplest definition, AM is manufacturing a part “from nothing”. No, you can’t make something from nothing but the manufacturing is done in such a way as to add to the part until it is finished, like building a wall out of bricks and cement in an empty area instead of carving a wall from a giant rock.

由于增材制造的特性，FDM(通常为3D打印)所生产的零件比传统生产的零件更坚固*且使用的材料更少*，但这两个零件都有一些隐含的条款和条件。 我在那里使用了3D打印的另一个术语(增材制造，AM)。 用最简单的定义，AM就是“从零开始”制造零件。 不，您不能一无所获，而要制造零件，直到零件完成为止，再进行制造，例如在空旷的地方用砖头和水泥砌成一堵墙，而不是从墙壁上雕刻一堵墙。巨石。

Additive manufacturing is the newest kid on the block when industrial manufacturing for mass consumer-production is concerned. Its more mature family members are Subtractive and Formative manfacturing. Subtractive manufacturing is, you guessed it, the removal of material from a stock object until your desired part is realised. Milling, turning, carving, grinding, cutting, tapping, threading, and a couple hundred more processes are all examples of subtractive techniques. Subtractive manufacturing is the old-reliable, and yes there is cutting edge tech involved, but the processes are established and well known. The disadvantages of throwing away anywhere from 20% to 90% of your stock material has been accepted long ago and its only the arrival of the new kid on the block that has started to make the masses reconsider. The digital-age comparison to a 3D printer is a CNC milling machine or lathe, and there is generally no limit to the materials that can be used for manufacturing but the designs are limited by the geometries of the subtractive cutting tools (#foreshadowing, see the images below).

当涉及用于大规模消费产品的工业制造时，增材制造是最新的趋势。 它比较成熟的家庭成员是减法和形成式制造。 您猜想减法制造是从库存对象中去除物料，直到实现所需的零件为止。 铣削，车削，雕刻，磨削，切割，攻丝，攻丝以及其他数百个工序都是减法技术的示例。 减法制造是可靠的，是的，虽然涉及到尖端技术，但是过程已经建立并且众所周知。 扔掉20％到90％的库存材料的缺点很早以前就已经被接受，并且这仅仅是新来的孩子进入市场的开始，这才开始引起大众的重新考虑。 与3D打印机进行数字时代的比较是使用CNC铣床或车床，通常对可用于制造的材料没有限制，但设计受到减法切削刀具的几何形状的限制(#foreshadowing，请参见下图)。

Formative Manufacturing is the middle child here, we don’t start from nothing and end up with the designed part, nor do we start with a big hunk of material and carve our way through to our designed part. Formative manufacturing is in a sweet spot where (by definition, not practice) all the material that we start with is converted from one shape into our desired shape. This is usually associated with materials that can deform or melt and cool. Pottery, glass blowing, metal casting, plastic moulding/forming, fibre-glass and ply-wood layering are the examples for this class of techniques. LEGO is a fantastic product example, and formative manufacturing really shines because of the speed of manufacturing we can achieve. The techniques are often limited by the shape of the shells we use to form these products and the cost of making these moulds and cavities are the biggest disadvantage by far. There is no easy tech comparison to a 3D printer here, the processes are not similar at all.

形成性制造在这里是中间的孩子，我们不是从零开始，直到设计零件，也不是从大量的材料开始，一直到设计零件。 成形加工处于最佳状态，在那里(根据定义，不是实践)，我们开始使用的所有材料都从一种形状转换为所需的形状。 这通常与可能变形或熔化和冷却的材料有关。 陶器，玻璃吹制，金属铸造，塑料模制/成型，玻璃纤维和胶合板层压是此类技术的示例。 乐高是一个了不起的产品示例，而成型制造的成功确实在于我们可以实现的制造速度。 该技术通常受到我们用来形成这些产品的壳体形状的限制，而制造这些模具和型腔的成本是迄今为止最大的缺点。 这里没有与3D打印机进行简单的技术比较，其过程根本不相似。

Was that an unannouced tangent? Lets go back to additive stuff again, please and thank you. So what is so great about all these different forms of additive manufacturing? This concept allows for part manufacture without cost of creating the mold or jig needed to make the part, but at the expense of time to manufacture. This is a huge advantage if you are a maker of custom pieces in small volumes, not so much if you are a major manufacturer of mass goods. But the real strength here is that the manufacturing technique allows for design that can use and abuse the power of geometry in difficult to reach areas without wasting material, and can also allow for some algorithmic design that completely ignores what you think a strong shape would look like and instead calculates the optimal shape that results in the best possible strength of the part.

那是一条毫不费力的切线吗？ 让我们再次回到加性的东西，请谢谢。 那么，所有这些不同形式的增材制造的最大优点是什么？ 该概念允许零件制造而无需花费制造零件所需的模具或夹具的成本，但会浪费制造时间。 如果您是小批量定制件的制造商，那么这是一个巨大的优势，而如果您是批量产品的主要制造商，那么优势就不那么多了。 但是，真正的优势在于，制造技术允许在不浪费材料的情况下，在不易到达的区域使用和滥用几何形状的设计，并且还可以进行某些算法设计，而这些算法完全忽略了您认为坚固的形状的外观像这样，而是计算出最佳形状，以使零件具有最佳的强度。

Truly deviating from the topic, here’s an impossible to mill/carve chess piece, and a wheelchair frame design cycle that should boggle the mind. The frames are produced with a different form of 3D printing (because metal) so technically this example is cheating, but I think this design is cooler than a few optimised shelf brackets.

真正偏离主题的是，这里不可能铣削/雕刻国际象棋棋子，并且轮椅框架的设计周期会令人费解。 框架是用不同形式的3D打印(因为金属)制成的，因此从技术上讲这个示例是作弊的，但是我认为这种设计比一些优化的搁板支架凉爽。

Lets now stop staring at the all stars of 3D printing and look closer to home. FDM was the topic, and because of how it works, stronger doesn’t always mean stronger. Before I showed you pretty pictures of organically designed wheelchairs, I mentioned FDM can produce stronger parts for less material than subtractive can. This statement is only valid in a max of 2 out of 3 dimensions because of the layer-by-layer effect. Very quickly, here’s some explanation for stronger* parts.

现在，让我们不再盯着3D打印的所有明星，而向家看。 FDM是主题，因为它的工作原理，并不总是意味着更强大。 在向您展示有机设计轮椅的漂亮图片之前，我曾提到FDM可以用比减法罐更少的材料来生产更坚固的零件。 由于逐层效应，此语句最多只能在3维中的2维有效。 很快，这里是一些更坚固的零件的解释。

切线2.5，好的...切线3。 (Tangent 2.5, okay fine… Tangent 3.)

Instead of going into the maths behind inter-layer bonding, I will rather use a simple example. If you’re in the need for some chopped wood and you have some log rounds and an axe, do you strike the wood with the axe blade on exposed wood aiming along the grain, or do you strike the log’s exterior and cut against the grain? Along the grain is the correct answer because the strength between the grains is less than the strength inside a grain (if science is your thing, van der Waals forces and hydrogen bonding are weaker than covalent bonding of the cellulose long carbon chains). TL;DR: logs and 3D printed objects hold good strength in 2 dimensions but suck at being strong in the 3rd.

我不愿使用层间绑定的数学方法，而是使用一个简单的示例。 如果您需要一些切碎的木材，并且有一些圆木和一把斧头，您是用斧头刀片将木片对准裸露的木材来击打木材，还是击打原木的外部并切下谷物？ 沿着晶粒是正确的答案，因为晶粒之间的强度小于晶粒内部的强度(如果科学的话，范德华力和氢键比纤维素长碳链的共价键弱)。 TL; DR：原木和3D打印物体在2维上具有良好的强度，但在3维上却坚固。

I’ve probably rambled away from my topic a little but hopefully I can wrap it all together now. The point I wanted to make is that 3D printing is fantastic set of processes with fantastic opportunities awaiting it as a technology in the future. But…Yes there is a but, for right now the only accessible printing technology is mostly used as a prototyping tool, or as a cosplay prop maker, a tabletop RPG miniature maker, or your DIY dream assistant in making that one of a kind thing to help you make some other thing. As it stands, 3D printing in the home is useful, mostly wasteful and decorative, but it wasn’t vital. All the tangents should be gone by now.

我可能已经稍微偏离了我的主题，但希望我现在可以将其全部打包。 我想说的是，3D打印是一套奇妙的过程，未来有很多机会等待着它成为一种技术。 但是……是的，但是，目前唯一可访问的打印技术主要用作原型制作工具，或者用作角色扮演道具制作人，台式RPG微型制作人或您的DIY梦想助手，以使这种事情成为现实。帮助您做出其他事情。 就目前而言，家庭中的3D打印很有用，主要是浪费和装饰性，但并不是至关重要的。 现在所有切线都应该消失了。

戏剧性的停顿：COVID-19… (Dramatic pause over: COVID-19…)

So March 16th was where I left off. A Monday I assumed would be like any other, except that through a small game of degrees of separation, I was potentially exposed to the virus that had recently found its way to South Africa. Luckily I was not infected, but between myself and my HR manager, it was decided that I should not step into the office if at all possible, and so my isolation and eventual quarantine-lockdown began.

所以3月16日是我离开的地方。 我认为星期一将与其他星期一一样，只是通过一小段分离程度的游戏，我可能接触到了最近发现进入南非的病毒。 幸运的是，我没有受到感染，但是在我自己和我的人力资源经理之间，我决定尽可能不进入办公室，因此开始隔离并最终隔离隔离。

While browsing Instagram, I spotted a post by Josef Prusa, a pretty big name in the 3D printing world. They had converted their printer farm of over 400 printers into an emergency face shield manufacturing facility to print the rigid frame of a face-shield, and use their warehousing and distribution departments to send these frames and the rest of the required bits to their medical facilities in Prague.

在浏览Instagram时，我发现了约瑟夫·普鲁萨(Josef Prusa)的帖子，这是3D打印世界中的一个大人物。 他们已将其拥有超过400台打印机的打印机场转换为紧急面罩制造厂，以打印面罩的刚性框架，并使用其仓储和分销部门将这些框架和其余所需的零件发送到医疗机构在布拉格。

Within a couple days this idea went global and my local 3D printing store sent out a call to action on their mail list. After some group politics, some red-tape and a few disagreements with some rather big names , 3DPSA and SA-fighting-covid was born.

在几天之内，这个想法就传遍了全球，我当地的3D打印商店在他们的邮件列表上发出了号召性用语。 经过一些集团政治，一些繁文ta节和一些与一些相当大的名字的分歧，3DPSA和SA战斗covid诞生了。

This non-profit organisation consisted of a few hundred local hobbyist 3D printer enthusiasts mass producing thousands of face shield frames from their homes and donating them to the COVID-19 task force, government medical staff and first responders that were in desperate need of PPE. Through some company donations of transparency plastic, plastic sheeting, rubber bands, 3D printing filament stock material and through sheer determination, 3DPSA has managed to print and deliver over 18 000 face shields to those in need.

这个非营利组织由数百名本地爱好者3D打印机爱好者组成，他们从家中批量生产了数千个面罩框架，并将其捐赠给了急需PPE的COVID-19工作队，政府医务人员和急救人员。 通过一些公司捐赠的透明塑料，塑料布，橡皮筋，3D打印长丝原料，并通过绝对的决心，3DPSA已成功印刷并向需要的人提供了18 000多个面罩。

I can’t claim to have been a huge contributor to this project, I have only had about 40 face shields collected from me and because of many other factors my printer is not really in production mode right now and I’m not in the mood for a house fire. Luckily, the community has some outstanding members and there are some that have printed several hundred face shields just by themselves. We have a leaderboard, therefore it’s a game/sport/challenge and all philanthropic ambition is out the window. Obviously that is not true, the group has gone above and beyond any expectation of any hobbyist society to make sure the people on the front-lines of this pandemic had some PPE in a time when there was basically nothing available.

我不能说自己为这个项目做出了巨大的贡献，我只从我那里收集了大约40个面罩，并且由于许多其他因素，我的打印机目前还没有真正进入生产模式，而且我也没有心情为房屋着火。 幸运的是，社区中有一些杰出的成员，有些成员仅凭自己印制了几百个面罩。 我们拥有排行榜，因此这是一场比赛/体育/挑战，所有慈善志向都在眼前。 显然，这是不对的，该小组超出了任何业余爱好者社会的期望，以确保在这种流行病的最前线的人们在基本上没有可用的时间提供某种个人防护装备。

This global movement sparked from hobbyist passion and determination, and there was some sheer dumb luck involved as well. There are other 3D projects on the go around the world to make respirator ducting, sleeves, braces, rigid face masks with filter template cutouts and a host of other parts, but none of them spread like the wild fire that was the face shield. The reason for this is quite simple, the face shield is a perfect part for FDM manufacture. Here is a picture of the face shield frame in some 3D printing software, which exaggerates the layer appearance. For the record, this is one of 3DPSA’s designs, and it is quite genius in it’s application. There is a small gap in the walls of the front round thingy (top-left corner of the part in this image) that opens up when the part is stretched outward, where we add the clear plastic sheet of the shield, and then closes and clamps the sheet in place when relaxed or stretched inward.

这种全球性运动是由业余爱好者的热情和决心引起的，并且还涉及到一些愚蠢的运气。 世界各地还有其他3D项目，用于制造呼吸器导管，袖子，支架，带有过滤器模板切口的刚性口罩和许多其他部件，但这些都不像野火那样蔓延开来。 原因很简单，面罩是FDM制造的理想选择。 这是某些3D打印软件中面罩框架的图片，放大了图层外观。 记录下来，这是3DPSA的设计之一，在其应用中相当天才。 当零件向外拉伸时，前轮物件的壁上有一个小缝隙(此图像中零件的左上角)，该零件打开时，我们在其中添加了透明的塑料防护板，然后关闭并放松或向内拉伸时，将其固定在适当的位置。

Let’s try and make all those tangents worth it, shall we? I mentioned that FDM was slower than industrial formative techniques, but the face shield design is simple, so all FDM printers (regardless of build quality) should be able to replicate the design easily and quickly. The crowd-sourcing of this initiative and the simplicity of the design allowed for massive production volumes. I also mentioned the FDM strength deficiencies that can be present in many printed objects due to complexity in shape and the 2/3 directions of strength. The layers of the design are identical, so there is less chance of printing failure due to complex movements and printing over empty space. But most importantly, the 2-axis printing direction matches perfectly to the planes of stress that the part will experience while it is used. This means that the design completely eliminates the weaknesses that FDM brought to the table, and the nature of additive manufacturing allowed for some very cool design features like 3DPSA’s crimp mechanism.

让我们尝试使所有这些切线都值得吗？ 我提到FDM比工业格式化技术要慢，但是面罩设计很简单，因此所有FDM打印机(无论构建质量如何)都应该能够轻松，快速地复制设计。 这项计划的众包和设计的简单性使大量生产成为可能。 我还提到了由于形状复杂和强度的2/3方向而在许多打印对象中可能存在的FDM强度不足。 设计的各层是相同的，因此由于复杂的移动和在空白空间上进行打印而导致打印失败的可能性较小。 但最重要的是，2轴打印方向与零件在使用时将承受的应力平面完全匹配。 这意味着该设计完全消除了FDM带来的弊端，而增材制造的性质允许一些非常酷的设计功能，例如3DPSA的压接机制。

So after several tangents, here we are. 3D printing can, and probably will be ground-breaking technology. One day. For now, I still think hobbyist 3D printers are very limited in their use, but every now and then there comes an opportunity for FDM to shine as a brilliant solution. For clarity, my Masters is definitely not one of these shining moments. But providing some relief, providing some purpose and motivation to many people that were in an emotional tail spin, and allowing a group of people to come together in solidarity to support the community, definitely is.

在几条切线之后，我们就在这里。 3D打印可以而且很可能是开创性的技术。 一天。 就目前而言，我仍然认为业余爱好者3D打印机的使用非常有限，但是FDM时不时地会有机会成为出色的解决方案。 为了清楚起见，我的大师赛绝对不是这些辉煌的时刻之一。 但是，一定要松一口气，为陷入情绪低落的许多人提供某种目的和动力，并允许一群人团结起来支持社区。

For more information, you can find SA-fighting-covid at https://www.southafricafightingcovid.com/

有关更多信息，请访问h ttps：//www.southafricafightingcovid.com/查找SA-fighting-covid。