An Interview with RepRap Developer Richard Horne

Note: Please keep in mind the English below is translated from an article that was written for Mainland Chinese readers engaged in hardware development and manufacturing. The goal of the series is to encourage contributing to Open Source and abiding by the license terms of projects when they are used. This is not a group of people known for embracing OSS/OSH principles so a less than "pure" stance and a good deal of diplomacy is required.

Some of the questions come from our hardware community (I am not quite that technical). Also, like most of my longer posts this has been proofread by native English speakers (my English is not this good) but I have checked to make sure that the final result is accurate- Naomi Wu.

An Interview with RepRap Developer Richard Horne

Naomi "SexyCyborg" Wu

For Chinese, it can be frustrating to only hear Westerners talk about us and not directly to us as valued members of a global community. This is the first of a series of interviews with the goal of building a more regular dialog between the Chinese and Western Open Source Hardware and 3D printing communities.

In this series, I also plan to focus on some specific technical issues- not simply the sort of general "feel good" graphs and projections so common at tech events that are more concerned with putting on a show than the specifics of figuring out how to build a global community that is engaged, profitable and practical.

Richard Horne (aka RichRap) is a well-known engineer, author and member of the RepRap Open Source 3D printer community from the UK. His designs and insight have brought countless improvements to consumer 3D printing. Mr. Horne was kind enough to agree to an interview on the subject of just what problems are waiting to be solved by China's best minds.

As Chinese, it is not simply an issue of earning respect and putting to rest claims that we can "only copy". There are practical reasons for us to solve these problems first. A 3D printer incorporating these improvements would not just have a unique sales advantage, attribution for the solution would earn the developers a position at nearly any international 3DP company.

Please remember that Mr. Horne is a passionate supporter of Open Source. As we are all aware, Open Source concepts don't always translate perfectly into the current social and economic realities of China. I- and many other Chinese believe that some if not all, of the principles espoused by the Open Source community, are worthy goals and represent a practical, proven path towards the innovative environment we all believe key to the continued success of modern China.

Naomi Wu: Over the last few years, the Chinese 3D printing industry has benefited a great deal from the RepRap project and other Open Source Hardware projects. Like anyone who has received assistance when starting out, now that we have some expertise and success many of us want to give back. What problems remain unsolved in the RepRap and Open Source Hardware community that you would like to see the Chinese hardware community work on?

Richard Horne: I see the RepRap project as a great way to allow new ideas to shine, so anything that users want and need is likely to get popular and maybe even developed into an 'industry standard'. Almost all ideas and developments with RepRap are judged on how useful they are for users or if a specific requirement has been addressed. It's survival of the fittest, but also a lot of random ideas should be encouraged.  With all that said, it's not just about the cost of things (or being 'free' ) - people will pay for good products and advancements of the project and also 3D printing in general.

One of the biggest problems all desktop and home 3D printers have at the moment is that they are still completely unaware of problems and failures. This really frustrates users and wastes a lot of material when things go wrong and keep on going wrong! I would really like to see a lot more work done to try and capture problems, and if possible do something about it or if not at least stop the print so material waste is limited.

Reliable new Innovations that could really help move on the RepRap project include -

Filament low sensor - a simple device that detects when the filament is running out and alerts the user. We have had many people work on this problem, but it's still not common to see a filament low sensor on 3D printers. Optical detection methods are not good because they get jammed up with fluff. Mechanical methods can fail or wear out. I would like to see a true analogue hall-effect filament sensor being used as a detection method. If you used a magnetic hall-sensor you can also measure the diameter of the filament and so that could also help the firmware auto-adjust to slight variations in diameter.

Feedback of stepper motors is the next - When a 3D printer axis skips or catches on a printed part and is knocked out of alignment, we need to detect that and alert the user or stop the print process. That could be done by adding encoders to the stepper motor's or even looking at the model being printed with a small camera and doing some basic image recognition that looks for a difference to the outside surface from what it's expecting.

It's not that I want to force standards, but it's so much easier for people to design a 3D printer if they know exactly what size and shape the filament material spools are likely to be sold to users and a standard helps that aspect and allows more choice of materials from different suppliers.

The next step in this is automatic filament identification for users - A simple solution to this is to have a sticker (Barcode / QR)  on each spool that can be scanned by the printer so all the correct settings are used without the user needing to guess or experiment and waste half the spool of material getting a good working profile for a new material.

You could add a RFID tag into the spool, but that's adding extra technology into a product where it's not really needed.

Lots of people in the RepRap community work on software tools but very few work on electronics, and mechanical enhancements, we do need more development on these sort of projects to allow firmware and software to have more control and intelligence about the printing process. Without the physical feedback it's going to continue to be frustrating for both new users and experts.

Naomi Wu: What do you see as the major obstacles to home/office adoption of 3D printing?

Richard Horne: Obstacles to more people using 3D printers are many of the above, but also that most people don't see or have a real need for 3D printed plastic parts. It currently takes way too long to print almost anything, and the average user does not see a benefit in daily life. I'm quite glad we are over the main 3D printing hype. Now it can focus on people who need the ability to 3D print, and slowly improve so more people can be involved when the entire technology tool-chain becomes more intuitive.

Naomi Wu: We've seen Lulzbot, Ultimaker and Prusa all successfully balance commercial considerations with their commitment to Open Source Hardware. In your opinion what are the keys to maintaining that balance?

Richard Horne: That is actually simple - You need to be truly open with every end-product you make, sell and support. You also need to build your own manufacturing IP that ensures you can meet both quality standards and demand as things pick up. Being Open-Source does not mean you need to tell every competitor how you manufacture a part or what tooling you designed to make the manufacturing process possible (or in software, what tools and skills you used to achieve the end result).

Holding back the release of a new design for 6 months after production release is not the answer. That method of 'Open-Source' some companies use really does not help their own community who wants to immediately improve and alter things when they buy the machine or product. The argument is that the company wants a head-start from copies and clones of the product. I don't see that really helping the adoption of a new machine or device for the original manufacturer, and it will not stop clones or copies.

Arduino manages to have a good brand loyalty and active community where people will pay more for a genuine controller from them directly. Yes, many will buy clones, but if you are not doing enough support, development and innovation to stay on top - and stand apart from the clones, you will not get a loyal community of followers and supporters.

The basic message is for a company to lead, not follow. And be confident that the source you release is being used under the license you stipulate and that's a good thing for your customers and as a wider mission of open-innovation (even with competitors).

Naomi Wu: Lastly, if you were to make your dream printer for under $2000USD, and would using only that printer- what would you use? Delta or cartesian- coreXY? Belts, string, screws? Direct drive or bowden? All metal or PTFE lined nozzles? We're a bit curious what you prefer at the moment.

Richard Horne: If that dream 3D printer was not just a one-off for me, but actually designed as a mass-production kit? - then I would use many more solid CNC style parts in the construction - Probably high-speed but small scale ball-screws, high-torque motors and a very solid frame. I would make it Cartesian but with a gantry style configuration so almost any type of surface/object could be printed on. I don't like moving print beds so all three X,Y and Z axis need to move quickly and precisely, with as low noise as possible.

My second choice would be using a similar style of very solid components, but in a SCARA or 6 axis of movement configuration. Again I like to have a fixed build platform, so a 3D printer that's more like a full moving axis robot-arm would be very high on my list of next generation 3D printers.

What I have just described above could easily be done as a kit of parts for assembly. It would be more expensive than most, but I think you could still do all that as a kit for under $2000.

For the Hot-end choice, I made a decision a long time ago that I could not build or buy a better hot-end than any of the E3D parts. So for me and every 3D printer I own the hot-ends from E3D are an essential choice. One of the main reasons for using a solid design based on CNC style components is that I would make the dream 3D printer a multi-tooled system. Many 3D printing heads and both a Laser head and possible small CNC routing head for milling and final finishing of printed parts.

I do also like RepRap designs, where much of the printer is 3D printed, so I would also like to see a micro-miniature 3D printer (FDM based, and very high quality printing output - tiny nozzles) that used high quality machined parts for the motion system, but with an almost completely 3D printed frame structure that anyone could print out themselves. I'm honestly surprised all of the above are not being offered by more Chinese or far-eastern suppliers. Good quality and low cost CNC are common, but many 3D printer kits are often more like flimsy toys only targeting a low price rather than extremely high quality movement systems and a solid frame.

Electronics are another big area for future development, but maybe we can talk about that in the next interview...

Naomi Wu: A great idea- I've taken up so much of your time already. Thank you very much Richard for taking the time to speak directly with the Chinese 3D printing community. Most of us know of and greatly admire your work.

Richard Horne: Thank you so much for the questions and I hope my thoughts and ideas help inspire more people to help the growing 3D printing community in whatever way that can.

You can see more of Richard Horne's work at:
https://www.youmagine.com/richrap/designs
https://github.com/RichRap
http://richrap.blogspot.com/
https://twitter.com/RichRap3D

一则与RepRap开源打印机原型开发者理查德.霍恩的采访

采访人：“机械妖姬”Naomi Wu


对于中国人来说，当我们听到西方的人只是讨论我们而不是让我们作为有价值的成员参与到全球性社区的对话里面是十分令人沮丧的。这则采访将会成为以促进建立中西两边开源硬件社区和3D打印社区交流为目的的一系列采访中的首例。

在这采访系列中，我也希望更多的把注意力放在技术性的问题上-不会像过往哪种在科技展览里面只是一味展示表现出自我感觉良好的图表或是最常见的对未来预测的作秀而不对如何建立一个主动参与的，有益的和实际性的全球性社区话题感兴趣。

理查德.霍恩（也称 RichRap)是一位来自英国的著名工程师，作家，和RepRap（开源3D打印机）社区的成员。他的设计和洞察力在家用型和小型的3D打印使用领域做出了不少改进。霍恩先生非常友善地答应了这则讨论有关什么问题有待由中国的聪明头脑去解决的采访。

作为中国人，我们不仅想要赢得尊重也希望慢慢改变我们在外界心中只会山寨的形象。而且背后有很实在的原因的就是我们需要第一时间去解决存在的问题。如果3D打印加入一些改善元素，这不但会给产品带来销售优势，而且会给提供解决办法的开发者在任何国际的3D打印公司里面赢得一个位置。

在这里请你们谨记霍恩先生是开源社区热情的支持者。我们其实都意识到，当今的西方开源概念并非总是能够很好地根据当今中国社会和经济现实翻译诠释。我-还有其他大部分的中国人都相信-如果不是所有的话，其中一些被拥护的开源社区的原则，是有价值意义的追随目标因为它们不但是在创新环境中被证实过是成功的，而且我们都相信这些准则会在日后如何持续发展现代化的中国起着关键性作用。

Naomi Wu: 在近过去几年中，中国3D打印工业在RepRap项目和其他开源硬件项目中获利不少。就像任何在最初发展时期获得过帮助的人一样，如今我们已经取得一定的专门技术和成功，当中大多数的人都想回馈社区。有什么在RepRap和开源硬件社区中还未解决的问题你觉得是我们可以尝试解决的？

Richard Horne: 我把RepRap的项目看作是可以突出新主意使其发光发亮的一种方式，因此任何顾客的需求都可能变得受欢迎甚至有可能发展到‘工业标准’。几乎所有RepRap的主意和发展都是据其对用户的实用性或是某个特定的需求是否已被解决来评估的。最优秀的一般会出类拔萃，但是也应该鼓励其他一大堆天马行空的主意。还有，不是所有都围绕事物本身的成本（或者“免费”）-只要产品和改良后的项目是好的人们还是会愿意为此付费的，对于3D打印来说也是如此。

其中一个最大的问题是现在市场上所有的桌面型和家用型的3D打印机还没有意识到存在的问题和故障。这不仅使用户感到挫败而且重复犯错还会浪费一大堆耗材！我希望更多人在打印的时候首先要抓住问题，如果可以纠正就尽力纠正，如果没有解决办法就应该暂停打印，不要一味的往错误方向走下去，这样就可以节省一笔耗材。


我认为可靠的可以真正帮助RepRap项目的新创意包括-


耗材低监控报警器-一个很简单的装置可以在耗材即将用完的时候提醒用户。我们之前有很多人都在致力于处理这个问题，但是这个装置在很多3D打印机领域还是不常见的。光电传感器不是理想的因为经过长期使用会被类似尘土和细小的微粒堵住。机械性的传感器可能会失败或者被用坏。我希望看到一个真正的类似霍尔传感器那样的被用作耗材传感器。如果你使用磁性的霍尔传感器你可以同时测量耗材的直径，这样的话当耗材直径发生微弱变化的时候可以帮助硬件进行自动调适去夹住耗材。

步进马达传感器是下一个重点 - 当在3D打印中出现跳轴或者一直在轴列外的点不停的磕磕撞撞的情况，我们需要尽快知道提醒用户去停止打印进程。我们可以尝试在步进马达旁边加上编码器，甚至是利用小型摄像头和利用在电脑里面的物体识别功能对比打印物体和虚拟文档里面的图片去观察打印物品的表面去防止变形或出差错。

我感觉我另外一个任务就是尽量去宣传鼓吹大家去规范化一款在3D打印里面全球性通用的线盘（支撑耗材的外壳）。所有的生产者去生产完全相同的尺寸，外形和同样大小的洞口（线盘一般是圆形的中间有一个空洞），最好是使用非常轻巧并且可循环利用的的环保材料-例如硬纸板或者是在垃圾中可自动降解的生物材料等等。在最近的几周我们看到Colorfabb在这方面迈出了第一步-他们希望为市场带来一款很轻巧的可自动生物降解的PLA耗材线盘-我希望其他的生产商也紧跟着这个步伐发展下去或者某天可以成为工业标准。我不想在2017年再去购买塑料型的耗材线盘啦。

不是说我想强制大家去规范这个标准，但是有了标准在设计3D打印机外观的时候就容易多了，他们会明确知道卖给用户耗材线盘的尺寸和外观，这方面也有助于用户不用担心线盘和3D打印机是否可以相匹配而是直接在商家里面选择采购不同的耗材。

下一步需要做的就是为客户设计一个可以自动识别耗材类型的产品-可以尝试把类似贴纸（条形码/QR码）这样的贴在每个线盘上面，让打印机可以对它进行自动扫描和自动辨识自动调节对其参数，这样就省去了用户需要每一次都为了新的耗材设置去猜测或者测试而浪费掉一大堆耗材。

其实也建议把类似RFID的标签放到线盘里面去，但是就为了怎么个外壳又外加技术性的产品其实也没啥必要。

很多在RepRap社区的人多数把注意力都集中于研究软件，只有少数人在研究如何改进硬件（一般大家只注重研究电脑里面的切片软件，但是没有更多地关注使用代码控制打印机的主板），或者是机械性方面的东西，我们的确需要更多人去探索研究这些项目以此达到硬件和软件在打印过程中能够更好的控制和提高打印机的灵敏度。如果没有得到打印机对打印过程的实质响应（打印机不是人，没有神经系统，需要传感器去回应打印过程)用户和专家都会因此感到挫败。

Naomi Wu: 你觉得对于在家用/办公室采用3D打印来说最大的障碍是什么？

Naomi Wu: 我们都见识过Lulzbot, Ultimaker还有Prusa在平衡商业策略和对开源硬件的承诺都是游刃有余的。在你眼里，你觉得他们维持平衡的关键点是什么？

Richard Horne: 其实道理很简单-你需要对每个你最后生产的产品都真诚公开，销售和提供售后支持。当然你也需要有属于自己的一个制造3D打印机的高效率低成本的工作流程。虽说要开源，但是并不代表你把所有的信息都公开出去，例如你不需要告诉你的竞争对手你是如何制造零件，或者你设计什么样的工具使你的制造流程灵活性更高（或者在软件方面的，不要把你如何完成制造目的所使用的工具和技能完全公开）

但在产品发布后六个月才新的设计发布出去肯定不是答案。一些公司的“产品开源”方法未必可以立刻满足那些购买他们机器或者产品想改善和改变东西的顾客。争议最大的就是怕把信息发布出去后就等于完全给其他公司泄漏了如何山寨和制造的信息。但是其实这对西方的厂家影响比较多一点，（因为很难使用低价格去购买一些原材料）但是在东方只要有了模型，（在购买原材料和分析如何制造的时候肯定东方占优势）就可以很快复制成品，所以你的焦虑是没什么用的。最重要的还是你的使用用户，当你的用户获取这些数据的时候才能更快更好地帮你改进你的漏洞然后再把资源公布出来免费帮助你修复漏洞（你永远不知道你的顾客是否只是普通购买者还是工程师愿意为这些难题专研的人），所以对原创原厂家来说，担心没有什么用，因为这不会阻止那些要复制的人，但是会阻止产品的发展进程。

Arduino很成功的为自己的品牌打造好的名声和维持对社区的忠诚度和活跃度，所以顾客愿意花更多的钱去购买真品而不是伪品。是的，很多人会选择购买山寨产品，但是如果没有足够的售前售后支持，利用产品的发展和创新去竞争-脱离单纯的复制基础，你永远不可能有追随者和支持者去忠于你所建立的社区。

简单要传递的一条信息就是对于公司来说最好就是成为开拓者，而不是成为潮流的追随者。而且你要对自己公开的信息有信心，因为你知道你的知识版权肯定多多少少都会被忽略，被践踏。但是在这种提倡开放式创新的情况下，开源不仅对你的用户来说是件好事。而且你日后得到的肯定比现在的要多（即使对你的竞争者来说亦是一样）

Naomi Wu: 最后一个问题，如果你在条件限制下要制造自己心目中的低于2000美金的3D打印机，而且只使用那款打印机-你会用什么类型的？Delta（三角洲） 还是cartesian（笛卡尔）-coreXY（三维导轨）? 用塑料传送带，绳子，梯形丝杆？直接跟喷头连接还是在喷头之外的地方连接挤压出丝器？喷头全部使用金属还是里面带有PTFE的喷头？我们目前非常好奇你对此的偏好。

Richard Horne: 如果那台3D打印机对于我来说不是一次性的，但属于大量生产的套餐系列？-那么我会在结构上使用更加坚固的CNC配件-我大概会用可以高速运转但是小型的滚珠螺杆，高启动转矩电机加上一个非常坚固的框架。我比较欣赏笛卡尔类型的打印机再加上个龙门架（没有打印机的自己想象一下，两条铁杆在打印机中间位置支撑马达和喷头，然后两条铁杆终端有个帮助推动杆子的辅助配件）

我的第二个选择会用类似上述的坚固配件，但是这款应该会由SCARA与6个移动关节点构成。重申一下我比较喜欢那种只有Z轴移动的热床，因此那种像机械臂XY轴移动的3D打印机绝对会是我下一个打印机的首选。

其实我上述的那些配件很容易可以作为一个可自己组装的套餐。虽然对比其他的可能要贵一些，但是我觉得在2000美金以下还是有可能的。

对于喷头的选择，很久以前我就做了一个决定，除了在E3D那里购买喷头以外，我知道自己是无法做到或者买到比这公司更好的配件。所以对于我来说每一台我所拥有的打印机的喷头都必须是来自E3D公司的。最主要的原因是如果使用CNC样式比较坚固的配件，我会希望我的理想打印机喷头是多功能的。多个3D打印喷头，激光喷头或是小型的数控镂铣头为最后的打印品打磨和清理最后的打印物品。

我的确也挺喜欢RepRap的设计，里面的打印机零件都可以被自行打印出来，所以我也希望在市面上看到FDM类型的迷你3D打印机（高质量的打印效果-加上微小的喷头）移动部分系统使用工厂做出来的高质量的硬件产品，其他外观上的可以使用自己打印出来的配件。其实我对于中国或者远东供应商还没有出售我上述的东西颇为惊讶。高质量低价格的CNC组装套件却是很常见，但是3D打印做出来的组装配套零件质量却不咋样的，好像市场上卖的廉价玩具，没有高端的移动系统也没有结实的框架。

3D打印的硬件提升在未来发展中有很大的进步空间，但是我们应该在下一个采访中才详细讨论这个问题。

Naomi Wu: 真是一个好主意-这个采访已经占据你怎么多时间了。我很感谢你抽空直接与中国的3D打印社区对话。我们很多人都认识你而且很欣赏你的作品。

Richard Horne: 很感谢你的这些问题，我希望我的一些想法和主意能够给更多人带来灵感去做一些力所能及的事情来扩展这个3D打印圈子。

你可以在这里看到更多理查德.霍恩的作品：
https://www.youmagine.com/richrap/designs
https://github.com/RichRap
http://richrap.blogspot.com/
https://twitter.com/RichRap3D