标签: CNC

A few weeks ago, I had a chat with Bill Parodi, an embedded systems designer and the founder of a recently-launched company called Draw2CNC that will be of interest to anyone who needs to create rapid prototypes.   Ten years ago, Bill founded an avionics company called UAV Navigation . When Bill and his colleagues were making their first inertial units, they discovered great services to prototype the electronic portions of their designs -- like ExpressPCB for the printed circuit boards -- but they couldn’t find anything similar to prototype the mechanical components (enclosures, mounting brackets, etc.). This forced them to use traditional machine shops, which have several shortcomings, including long lead times and multiple iterations on designs to match manufacturing capabilities.   The way this typically works is that you generate your 3D CAD drawings using an expensive and hard-to-use program. You send these drawings to the machine shop; the folks at the machine shop examine the drawings and inform you as to any elements in your design that may cause manufacturing problems; you re-spin your drawings and return them to the machine shop; and so it goes. At the end of the day, the folks at the machine shop are going to bundle all of their service and support costs into the price of your prototype.   Now, although there are some companies that do provide mechanical prototyping services, such as Front Panel Express , these companies tend to work with 2D objects. What Bill required was the ability to quickly and easily prototype 3D mechanical objects.   Based on his experiences, Bill decided to create a solution that would offer the simplest way to draw something and have it machined in a few days. The key features Bill wanted to provide with his solution are that end users should not have to purchase expensive and hard-to-learn-and-use CAD programs, they should not need to iterate their designs to match manufacturing capabilities, and they should not obliged to commit to large orders.   Bill crafted his solution, Draw2CNC , based on his experiences with ExpressPCB. The idea here is that the folks at ExpressPCB provide a free schematic capture and board layout package. This is a stripped-down, no-frills package with limited capabilities, but with the corresponding advantage that it's quick to learn and easy to use. More importantly, this package is 100% integrated with their board manufacturing process, which means that it simply isn’t possibly to create a design that cannot be manufactured. Once you're happy with your design, you press the "Go" button and your boards are manufactured.   Similarly, in the case of Draw2CNC, you start by selecting the type of material you wish to use and the size of the block with which you wish to work. The materials that are currently supported are 6061T6 aluminum (with an optional post-machining alodyne treatment) or Teflon, but Bill is planning on adding additional material options over time.   You then use the free Draw2CNC 3D CAD software to draw arbitrary cuts in five of the block's six sides. The great thing here is that the Draw2CNC software won't let you create a design that cannot be manufactured.   This enclosure for a Raspberry Pi single board computer was created entirely using Draw2CNC, including the enclosure itself (alodyned aluminum), the lid (not shown here), and the port covers (Teflon, also not shown here).   When you are ready to rock-and-roll, Draw2CNC will give you a detailed quote that breaks our material costs and machining costs (based on the complexity of the design). Once you press the "Go" button, the standard manufacturing time is eight working days from order to shipping (an express process is also available).   Personally, I think this is a brilliant concept. There are all sorts of small mechanical parts I wish I could have had fabricated over the years. In fact, now that I come to think about it, I have a current project that could benefit from a little tender loving care by Draw2CNC; watch this space...

虽然刚看过拉斯维加斯的CES，上面也有无数的机器人，但今天在深圳高交会馆举办的第十六届深圳国际机械制造工业展览会（以下简称“深圳机械展”）、智能集成及机器人技术展览会上，看见英国超级机器人Titan（泰坦）还是令我十分吃惊。其跳舞、走路、爬楼梯的动作灵活性、人机语音交互的机智，都超过了我在CES上看到的机器人。   泰坦也被称为“地球上最大的艺人”，身高达2.4米。曾周游美国、澳大利亚、阿联酋、泰国、越南、卡塔尔、爱尔兰、西班牙、法国、荷兰、德国、捷克、土耳其和丹麦等多个国家，这次是在中国首秀。“第十六届深圳机械展”今起至4月2日在会展中心盛大举行，对机器人感兴趣的赶紧来看吧。下面我给出一组图来秀秀“泰坦”，但这些静止的画面绝对没有面对对看到时震撼。我在微信朋友圈发了两小段视频，大家都发出惊呼。（后来得知他是一个由真人演员穿戴的机器人道具，也称为高仿机器人，主要部位由人体控制，其余部位遥控，如果哪一天真的机器人到这种智能与灵敏度，那人类是不是就会受到巨大挑战了？） 这个就是全球著名的“超级机器人” Titan。别看他身材魁梧2.4米，但是行动绝对自如灵敏。       Titan泰坦舞姿优美，模仿这个舞者惟妙惟肖。     深圳市副市长陈彪出席了今天下午举办的“第二届机器人应用技术主题论坛，他对于Titan的喜爱与兴奋，大家从他的脸上可以读出吧？这时，TiTan还说：“请给我点二十个赞！”哈哈，好风趣的Titan！   小标题：工业4.0与火爆的CNC   除机器人外， 这次 深圳机械展， 工业4.0与CNC相关的内容十分火爆。环球资源《世界经理人》的发行人裴克为作了有关“工业4.0"市场的主题报告，他指出，工业1.0是机械化生产，2.0是更多的设备自动化和大规模生产，3.0是设备互联网化，那么4.0则是云计算和大数据为基础，同时针对小批量买家提供更定制化的服务。顺便提一下，我们公司老外的流利普通话，不输下面的听众哈。     另外，随着智能手机追求更纤薄的机身与更细腻的手感、更酷眩的外观，CNC加工也成为此次展会的大热点。国际厂商与本土厂商的很多技术创新也围绕它展开。   比如这个三菱电机推出的新一代M80生产管理设备，就是可以通过抑制机械振动，使得转角可通过速度UP平滑动作，提升良率和效率。   这家名为刀豆科技的公司，通过提供高技术刀具与综合加工的办法，解决CNC加工面临的效率与客户严苛的质量挑战。

Good grief--how time flies! I first determined to build my Bodacious Acoustic Diagnostic Astoundingly Superior Spectromatic (BADASS) display way back in the mists of time we used to call April 2014, so this project has already been running for around two thirds of a year.   On the one hand, this does seem like a rather long time. On the other hand, when I think of how much is involved, and also how I'm interleaving this with a bunch of other projects, it really doesn’t seem all that bad.   In this column I thought I'd bring you up to date with the current state-of-play, and also explain the comedy of errors I've been making recently. But before we plunge into the fray with gusto and abandon, on the off-chance you aren’t overly familiar with this project, the following table of article links will describe how we've gone from an initial concept like this...     ...to the present incarnation of my little beauty, which looks like the following (note that this image was taken in my driveway after I'd finished working on it this past weekend, which explains the houses in the background):   Phew! When I come to look back on all of these articles, I think it's amazing I've come as far as I have in only eight months (LOL). And so we come to the recent series of mishaps that I've been fighting my way through.   Here's the main cabinet sitting on our back porch. I brought it outside because -- for some reason -- I couldn’t manage to take a decent picture inside. I routed out the main panel in the middle, while my master-carpenter chum, Bob, made the surrounding cabinet.   I must admit that I was quite proud of this because it was the first time I'd ever routed anything. The only slight slip-up was the left-most vertical channel in which I set the jig up the wrong way, but since this won’t be seen by the user, I'm not losing any sleep over it.   In the image below we see the large display panel and the smaller control panel -- both made out of hardboard (pressed-board) painted to look like brass -- attached to the main front panel. This scene all looks so innocent, doesn’t it? In reality, however, there were numerous "gotcha's" that reared up to bite me.   Let's start with the display and control panels. Initially, I created these out of 1/8" hardboard, which I lovingly crafted to fit into my routed front panel. I'm not a woodworking expert, so this took me quite a lot of time. When it came to drilling the holes for the acorn nuts around the edges and the array of lenses in the middle, I worried that there would be small but annoying errors if I did this by hand. Thus, my chum Willie whipped up an engineering drawing to drive a CNC machine, and my friend David at a fabrication facility just down the road ran the panels through his machines.   Unfortunately... David made a similar mistake to mine -- he subtracted 7/32" instead of adding it to the 0,0 point, with the result that all of the holes ended up 7/16" out of whack.   "Oh dear," we both said (or words to that effect). This was a bit of a blow, and no mistake, but these things are sent to try us, so I got another piece of pressed board and we tried again. This time David drilled the holes first, and then carpenter Bob shaped the panels to match the routed areas.   Now I ran into a new problem, which was that the original hardboard was 1/8" thick, while the new sheet was 3/16" thick, which meant it protruded in front of the main front panel by 1/16" instead of being flush. "Oh, well," I thought, that doesn’t really matter. Actually, if the truth be told, having the display and control panels protrude by 1/16" actually looks rather good. "Things all work out well in the end," I said to myself, cheerfully, little realizing the horrors that were to come... Just to remind ourselves, we left the cabinet in the state shown below, with the display and control panels attached to the main front panel using brass acorn nuts. Ah, if only that were all that was holding things together. As fate would have it, however, before I attached the acorn nuts, I realized that the hardboard was bowing out a little in the middle. "I'll never need to take these panels off again," I thought, "so there won't be any problem if I glue them to the main front panel."   So that's that I did. I lay the whole cabinet on its back, glued the display and control panels in place (using the four corner bolts to lock in the alignment), and weighted everything down with books until the glue had set. Then I removed the books, stood the cabinet up, and attached the remaining acorn nuts and bolts, leaving things as shown above.   It was only then that I turned the cabinet around to look at things from a rear perspective. You can only imagine my disbelieving horror when I observed that the vertical channels I'd routed were obscuring the edges of the holes for the Fresnel lens/LED assemblies as shown below.   "Well, that's a tad unfortunate," I said to myself (or -- you guessed it -- words to that effect). Now, it wouldn't have been a major effort to widen these channels in the main panel using my router, if only some plonker hadn't gone and glued the display panel onto the main panel (sob sob).   This is where another Bob comes into the picture. (I'm like the little boy in The Sixth Sense movie -- "I see Bobs everywhere"). This Bob is ensconced in the office next to me. While I was bemoaning my fate to Bob, he explained that he is a master at making mistakes, which has helped hone his skills for rectifying them again. After I'd explained the problem, Bob helped me to devise a solution.   In the image below we see the simple jig Bob and I concocted to allow me to widen the channels without having to remove all of the acorn nuts and bolts. The router bit is set to such a precise depth that it completely removes the main panel material whilst leaving the rough backside of the hardboard totally unscathed.   Now we were really cooking on a hot stove, as it were. The following two images show the cabinet with its 16 x 16 = 256 array of Fresnel lens/brass washer assemblies attached (once again, both of these images were taken in my driveway after I'd finished working on my little beauty this past weekend, which explains the houses in the background).       Well, when I say "attached"... as fate would have it, there's a teeny-weeny problem. The body of each plastic Fresnel lens is threaded, and each lens comes with an associated plastic threaded ferrule-type thingamabob that screws on behind the panel to hold its lens in place.   Initially, I was thinking that these ferrules would be all I would need to attach the lens-washer assemblies to the display panel. The thing is that the brass washers hold the lenses a little way in front of the panel, so only a small portion of the threaded backside of the lens protrudes through the back of the panel. If only the panel were 1/16" inch thinner -- but no, some drongo had to go and replace the original 1/8" thick panel with a 3/16" version.   Isn't it amazing how little decisions can come back to bite one downstream in the development process? The end result is that I now need to glue the ferrules onto the backside of the lenses. The ideal adhesive should be something that works with hardboard and with different types of plastics (including PVC derivatives, which is what the ferrules appear to be made out of). This adhesive should be thin enough to be applied with a paintbrush or by dipping the end of the ferrule into it. It should give me a "work" time of say 20 to 30 minutes so I can pour some into a small bowl and work with it without it drying out too quickly. It should dry white or transparent so as to not absorb any of the light from the LEDs, and it should not dry brittle because I don't want it to crack if I move the cabinet around. Do you have any suggestions?   I don't know about you, but even with these little "gotchas," I think this BADASS Display starting to look very, very cool. The next step -- after I've finally fixed the lens-washer assemblies in place -- is to add the LEDs and the control electronics. I have all of this standing by. I really think there is a good chance I will have everything completed by the end of the Christmas holidays (apart from the final programming, of course). Watch this space for ongoing developments...

第一部CNC 應不應該自己製作呢? 因為想自己做CNC, 所以有幾點考慮: 1) 精準度 - 第一部CNC是買的, 可作為參考及比較! 2) 成功機會 - 買的CNC是一定會動!  3) 容易度 - 有了買的CNC, 就容易生產自己設計的CNC. 以上考慮 對嗎? 想請教大家!!