Another mill is something else | Hacker Day

2021-12-08 08:15:46 By : Mr. Michael Xu

I will admit. When I first saw Othermill, I thought it was just another factory with cheap Chinese hardware, sold at a premium. I am ashamed to say that I even talked a little nonsense. This gave me another opportunity to realize that I should do research and thoroughly check my hypothesis before becoming an asshole. Even so, it is not recommended. Another machine company kindly let me hang out in my office in Berkeley, California. The CEO [Danielle] led me to complete the design of the factory and the challenges in operation.

Othermill is a serious machine, and it will only get better with the recently released Othermill Pro. The components are not a bargain basement. This may be more obvious, but it is made almost entirely from parts sourced in the United States, including custom stepper motors. No ball bearing will start to make strange noises within a year. It can now cut 6 million traces on the PCB all day. Put it in perspective. The cost of Othermill Pro is one-third of the price of an equivalent LPKF machine, and it has the same features.

The Othermill was originally a DARPA grant researched at Otherlab. They hope that every classroom has a cheap, durable and easy-to-understand CNC that has the same functions as a laser cutting machine, but without toxic gases or fire hazards. This resulted in a strange looking machine. This machine works exactly like a vinyl cutter with a spindle instead of a blade. The sheet is fed into the drum, which moves the material back and forth until it is finished. I have some doubts about the design, but [Danielle] assured me that it works well. Since she has a PhD and is the CEO of a CNC machine tool company, I still tend to believe her.

However, this machine is not the one we see today. As always, the government was erratic, seeing a newer, brighter button on the floor, staggering, running, throwing Othermill's research project from its squishy fingers. Almost all the funds were used up, and other machine companies should give up. Instead, they reorganized and accepted some work just to keep normal operations and work towards Kickstarter.

The next iteration of their machine, and the machine shown in the Kickstarter video, began to transform into the other factories we see today. Interestingly, this machine has no fasteners at first. This is a cool design choice and has some advantages, but it is not enough compared to using fasteners. Machining is more expensive, and machines are more difficult to repair.

Throughout the development process of the final version of Kickstarter, the machine has undergone a lot of upgrades. It has grown a handle. It has a closed build volume. The wires are well managed. Most importantly, they added a very good software stack. The level of polishing is impressive.

In the end, it worked. Other machine companies did not close down. It strives to achieve sufficient financial independence, spin-off from other laboratories and owns its own facilities in Berkeley.

For amateurs who stumbled across Othermill, it is difficult to understand why it is so costly. Ebay is flush with 3,020 CNC milling machines from China at one-third the price. Why would someone put the extra cash on a machine with very similar specifications on paper? These specifications are good, but all specifications were written with all specifications aligned, the chief engineer only spent three days adjusting the equipment, the marketing was a bit drunk, and the CEO was grumpy.

Paper specifications will give you an expected indication, but evaluating real-world performance will give you the truth. Even top CNC machines with exactly the same specifications may perform differently in terms of cutting, noise, vibration, surface finish, and speed. If this were not the case, they would not endlessly pester the company with salespersons. They just post the lowest price and people will buy it.

Vibration is a subtle thing in CNC machine tools. By its very nature, the machine makes a lot of noise, throws chips everywhere, and usually makes a mess. If you put a good CNC next to an equivalent bad one and run them side by side with the same settings, it is usually difficult to immediately notice the real obvious difference. However, when it is necessary to assemble two parts together or check the surface finish of the parts, the truth becomes obvious. Vibration is very important.

As shown in the picture on the right, it is easy to see the effect of vibration in the sister machine 3D printer. The dynamic forces on the frame all add up to produce repeatable ringing in the plastic. You can actually see the nodes and antinodes on the printed wall. By changing the speed and acceleration settings, users can reduce these forces on the printer until a smooth effect is printed.

Now, add a rotating end mill and see intermittent loads of different sizes, depending on the entire variable from material type to moon phase, and vibration issues in CNC milling machines become easier to see.

Mentioning the 3020 mill again, here is a great slow motion video where the spindle will occasionally deflect and vibrate back to zero. It is difficult to detect this behavior with the naked eye. Keep in mind that this device is expected to achieve almost the same positioning accuracy as Othermill, however, it usually deviates from the spindle load by more than 0.01 inches.

The main shaft on the 3020 is a cast and lightly machined bearing housing, press-fitted to the front of the brushless motor housing. Any vibration generated inside the motor will directly affect the parts. In addition, the rolled sheet metal shell does not have enough metal to provide sufficient resistance. This video explains how some serious design flaws in these spindles can cause big jumps. It also mentioned that it is possible to destroy these spindles in about 4 hours, and the cutting machine should be a milling machine. There is a reason why most (but not all) sellers' markets are CNC engraving machines rather than milling machines.

Othermill has a custom machined spindle housing with top-of-the-line chuck with fixed drill. The spindle has a set of correctly matched precision ball bearings, which have been correctly preloaded.

By using belt drive instead of direct drive, the motor is separated from the action of the end mill. These belts must be carefully selected and will eventually wear out due to the heat and mechanical stress of daily operation. This small compromise (the belt is cheap and easy to replace) is worth it. The Othermill also recently manufactured a customized spindle motor for them, which is higher performance and quieter than the R/C motor they used before. Someone told me that their new motor meets the same dynamic balance standards as hard drives.

All these add up to make the spindle quiet, precise, durable, and capable of withstanding amazing loads for such a small machine. The actual runout of this spindle is significantly lower than that of the Chinese spindle.

Okay, but the Chinese factories are made of aluminum, while other factories are just some crappy plastic. There is no doubt that aluminum is an excellent material for rolling mills. This is not true.

The frame Othermill is made of machined HDPE. According to the aluminum alloy to which it is compared, HDPE can be stronger than aluminum while offering many obvious advantages.

HDPE suppresses damping better than aluminum. All these tiny vibrations will accumulate in the machine. HDPE can convert some of these vibrations into heat. In contrast, aluminum will transmit most of the vibration rigidly, just like a spring. This means that the forces and oscillations of the cutting and movement of the machine must go somewhere. Usually this is the joint that enters the machine; that is the end mill and the bearing. If not handled properly, this can cause anything from poor surface finish to premature failure of the machine. For Othermill, this leads to quieter and more accurate operation.

They also used flexible joints to align the smooth rods, cleverly taking advantage of the greater flexibility of plastic. One rod is fixed in the frame, and the other can be moved from left to right, but not up and down at the other end. Compared to the load that the machine will see, this is actually a very robust structure that prevents any misalignment static friction problems or premature wear that may occur with the linear guide bearing setup

HDPE is much lighter than aluminum. This is a good thing for the spindle bracket and other moving parts in the mill and the portability of the mill. The heavier the bracket, the stronger the dynamic force on the frame. The gantry design of the Chinese rolling mill moves a considerable amount of weight for such a small machine. When the machine is moving fast, this will cause a lot of vibration, noise and more deflection.

Of course, as shown in the spindle assembly above, where aluminum is required to have higher rigidity, Other Machine Co chose it as the material. HDPE can cause a bad spindle housing. It expands too much when it is hot. It deflects too much to accurately keep the bearing.

HDPE is cheaper than the equivalent aluminum alloy. This reduces the cost of the machine. Since plastic is cheaper, they can use more plastic. In terms of volume alone, the othermill uses much more material in its frame than the 3020 mill. This results in a machine with a very strong, light and closed frame.

HDPE is not only cheaper, but it cuts like butter on a correctly set machine. This allows them to perform very complex cuts, which are too expensive for metals. We will see later. They can even cut grooves in the walls of the machine to achieve very neat wiring.

For the sturdy frame and spindle, the only significant mechanical element that needs to be compared is the linear motion mechanism of the respective CNC machine tool. The 3020 mill is known for occasionally offering ball screws and linear guides in its price range. However, it is well known that a ball screw is a difficult object to manufacture, and as many people have experienced, if it cannot be rotated, it is of little value.

The 3020 factory varies from seller to seller. Some provide ACME screws, others provide, usually, C7 precision ball screws or ground ball screws. Adding the complexity of a ball screw to such a small mill is not necessarily a selling point. One of the advantages of ball screws, especially in large machines, is the low friction under load. However, the drives of these large machines are so large and the moving weight is so large that the inertia of the screws and the vibration and noise from them become negligible. Generally, compared with 3020 mills, ball screws can better prevent grinding particles.

Othermill uses Teflon-coated precision rolling screws from Koco Motion in the United States. With the correct matching anti-backlash screw nut, they can match the performance of the C7 ball screw without any complicated shortcomings of the ball screw. The Teflon coating eliminates most of the driving force differences between the two.

Although the Othermill and 3020 both use circular linear guides, the 3020 usually uses roller bearings, while the Othermill uses more expensive PTFE-impregnated acetal bushings. When preloaded correctly, these bushings are not only the same or more accurate. Likewise, compared to roller elements, they have far fewer noise issues, wear issues, maintenance and vibration issues. This can be seen in the comparison video below.

It is easy to assume that a $600 factory will have very cheap electronics. All of the electronics in these factories are designed to run on parallel port computers. Therefore, with your purchase, you must find a suitable old computer to actually run the factory's Mach 3 software. (LinuxCNC is also possible.)

In addition to higher power consumption and higher noise caused by lower PWM frequency, both Mach 3 and Linux CNC currently support S-curve acceleration without some serious hacking attacks. As this video shows, this can make a big difference for a machine in motion. Not only will the load on the tool be more uniform, but also the vibration of the machine will be smaller.

TinyG is also a tried-and-tested motherboard that has received a lot of support. The Chinese factories will be equipped with electronic devices that have undergone the heaviest bean counts and only the roughest tests. Under normal use, they are likely to be damaged. We have introduced a user's experience with the electronic equipment of the 3020 rolling mill. The first thing he must do is to completely replace the power supply. Some excavation and hacking are needed to enable functions such as spindle speed control that should have been enabled.

Finally, the electrical connection of Othermill is more reliable. 3020 factories usually need to route and terminate a certain length of wire in the cheapest DIN connector they can find. These are hardly reliable connections for milling machines.

Othermill's goal is to be a portable machine, so a lot of work has been done on the correct wiring and termination of the correct wiring. There is a lot of work to be done. For example, if you are just trying to use standard Belkin Telecom cables or ribbon cables for CNC machines, you will soon find that the wires are disconnected intermittently when they are moved anywhere (look at your Makerbot!). Wiring must be designed for flexible applications or they will break. This costs money, and the company will do all kinds of things, from special plastic structures and complex braided wires to placing Teflon powder between conductors to realize flexible cables.

The final difference is one of QC. Importing factories will definitely need end users to do some work to get close to the promised specifications. We have seen users do everything from replacing all electronic equipment to replacing more expensive spindles. The machines are likely to be uneven, and it may be very difficult to adjust one of the machines.

Like most high-end/domestic-manufactured products, Othermill has undergone more testing and calibration before leaving the factory. The mill is moved and the bed is ground to be completely parallel to the stroke of the machine. Electronic equipment is checked and everything is tracked. The level of support provided by other machine companies is higher than the level of support provided by Chinese manufacturers.

The last thing worth mentioning is Othermill's software stack, especially PCB. This is one of their most touted selling points. See it in action. It can definitely be used as an advertisement, and if they make circuit boards, it will especially make their lives easier.

However, in the case of regular machine work, LinuxCNC or Mach3 is not difficult to master. In the final analysis, having any type of CNC still requires some technical knowledge and the ability to read documents. Once all the settings are completed, it's basically just a click.

After all, all of this adds up to a machine that cuts in the same way every time. As an added benefit, it will also be much quieter than other options. When performing circuit board wiring operations without hearing protection, I was able to sit next to it. A well-structured machine is durable; so far, I have seen four other mills in the wild, and they are all used extensively. They can mill a variety of materials with precision, and occasionally perform maintenance, they should last a long time before major failures occur

On the other hand, in theory, import factories can adopt the same specifications as Othermill (thus matching their promised specifications). However, this will require a lot of time and money investment.

Mechanical engineering is a completely different beast. Interestingly, when researching for this article, I saw that some of my assumptions before writing this article were not as correct as I thought. For example, I think that any grade of ball screw will outperform ACME threads. I believe that many of you have more experience and education than mine. Looking forward to comments.

Disclaimer: When looking for something to write, I asked other machine companies if they could visit their offices. I currently do not own other factories, and other factories have not given me any benefit of writing this article. All the subjective and objective views in this article are my personal views as a working engineer who happens to write for Hackaday. Hackaday does sell Othermill in its store and has one in the Supply Frame Design Lab, but this has nothing to do with my writing. I do think that no one has thought about giving me at least a ridiculously sized bag of cash (rejecting of course) to get a positive review, which is rude. This is just polite.

Praise the hatred of the Chinese.

Every country has its share of idiots.

We have a small Taig CNC milling machine in school and we know why carbon steel is better than aluminum/plastic/wood/dog shit construction technology.

Yes, all that is missing is a huge American flag in the background of the page.

This great American entrepreneur has built some reputation for "quality", before they fire everyone, outsource to China and get extra lucrative profits until retirement. But when "hackers" like to be fooled by every new startup that feeds on nationalism, why stop?

It would be great if the "Maker" movement could make America great again.

I have no idea. If this machine is as reliable and repeatable as the article says, it will become a prototyping tool for all other companies, whether it is a start-up company or a company with mature engineers. 3300bux is a very, very small price to pay for reliable things in a business environment, which can make up for the labor cost of this machine and the $400 3020 machine in the real world far more than the cost of a machine like this. A typical hacker in hell will buy a Chinese one, even if it's $400, while the lower quality is $350. I suspect this is something a timid hacker would buy, hell most hackers would not even buy $400, they still develop pcbs or use through-hole breadboards and solder their lives. I know that I cannot prove the reason for owning a dedicated PCB factory. Can you?

totally agree. The price of this CNC is 10 times that of the Chinese CNC. If we compare $1 to $10, the whole discussion will be meaningless, but in the range of $100 to $1,000, the situation is different. Is it really worth paying 10 times the price? What is the credibility of Western arrogance? We keep repeating this mantra: Our trash is more expensive than China's because China makes trash.

I don't hate China. Read the article. Look, these kits are sold at the lowest price and there is no long-term support. This is the goal of their manufacturing process, and they want consumers to understand where costs are being cut. Now, other companies like Up!, Marriott, Rongfu, Xiaomi and Rigol are great. no problem. When I was arguing at http://hackaday.com/2016/01/18/whats-in-a-tool-a-case-for-made-in-usa/, I was not actually against China. I am opposed to separating your manufacturing from the part of the company that knows your product. Take Othermill as an example. Because their output is so low, but the equipment is very sophisticated, it is absolutely meaningful to establish close partnerships with domestic suppliers. They can handle smaller orders, interact more closely with outsourced engineers, and generally maintain a higher level of control over their products.

"I have some doubts about the design, but [Danielle] assured me that it works well. Since she has a PhD and is the CEO of a CNC machine tool company, I tend to believe her."

The logic fails. Appeal to the authorities

I don’t remember how to post pictures...

Mod Edit, I got fam

http://i3.kym-cdn.com/photos/images/original/000/995/552/169.jpg

When I read that sentence and looked at the author, I was not surprised. This is the writing style of Gerrit Coetzee. If I only need a PhD, I have a cool bridge, and I am crowdsourcing on kickstarter. I have a doctorate with nonsense.

If (! Logic) {printf("article"); exit("hacker day homepage");}

If it’s attractive, credibility helps. https://othermachine.co/company/about/

Thank you for your laughter. There is nothing better than a 2/3 female engineering team, but an old feminist slogan.

It doesn't matter who the engineering team is. I think the whole problem with this is that there is prejudice and selling things that shouldn't even be considered hackers. This really shouldn't be an article, I would rather add it as a supplement.

What I am even more annoyed is that the actual good hackers/modules/novel ideas on this website are completely reduced, and product advertisements or tore up Reddit posts 2 weeks ago. New toys are one thing, but they cannot solve the problem, nor can they provide anything for people to learn. If I look back a few pages, most of the articles I see are about new circuit boards, clumsy products, and crappy redesigns of things designed for "hackers" (the "manufacturers" of marketing cartels).

This is another kind of "nerdy cool" type of thing, someone will buy, play for an hour or two, and then throw it on their resume, saying that they are "experienced CNC machine tools." Thanks to Gerrit for another very biased product placement article, it has no educational significance to anyone.

Seriously, if you want to have a "new" or "coming soon" product, please have a separate code on the homepage. Call it the "coming toy". This way, you will still get whatever income and things they will pay you, but this content will be filtered out of the actual "hacker" and then linked to the upcoming related products so that people can see the entire competitive environment . New 3D printer? Use 3D printing to place it in the new toy part. This way people can compare it with other printers in the past, and real specifications and figures are coming soon, rather than the hype and marketing that some PhDs have said. In this way, you can obtain real specifications and conduct real reviews without clogging the rest of the article because ad-based spam is used as a "hacker". I know you need to run a website, which is a business, but you are severely stifling your bottom line here.

In terms of knowledge and insight, you are sitting in a bloody gold mine for yourself and the entire community here, and you are panning for gold in a river a mile away. I think on behalf of most people here, we are happy to support a website that has hacks, but there is also an organized way to view products with real data before we buy. If you can do it, everyone will win. You already have a platform, a community, and even a storefront. What else do you really need?

I don't know where you got this kind of bitterness, but anyway. Personally, I would buy a Taig because I am a robot and I want a throwing knife, but it will still make you flinch. Although cemented carbide is very cheap now, my first trick is to put a $300 water-cooled high-speed Chinese spindle and vfd combination on it for fun. The difference is if you want to optimize the cost for several days and get the same result: buy a Chinese factory. If you want to take it out of the box to work, buy an Othermill, used lpkf, or roland or something.

Hackaday did not get a "cut" for this article, nor did I. We do not do this. I originally planned to write a shorter article, but then I went into technical comparison because I guessed I was a huge nerd and was taken away.

@Theo-I hope I disagree with you, but I really agree. Before I put in the time to actually read and absorb the content, it is frustrating to have to browse the article in question to determine if it is a blatant advertisement. I am not a person who usually complains; I admire the site and (most) community members, but feel that I have lost some management perspectives in the rush to get a lot of content on the treadmill and before going out. I don't have a solution, but can someone edit these posts for grammatical and spelling errors at least before they go live? Excellent performance in simple things!

Hey Hubert and Doub, the 1800s are called... they want to restore their perception of women.

I know, I am super handsome;)

but. You hear the name of a woman, look up their photos, and then use their appearance to discredit them. Maybe you need to do some introspection.

I am replying here because there does not seem to be a reply button on other replies.

When you talk about technology comparison, I haven't seen any comparison based on quantitative evidence. There is no review of the "Made in China" CNC and this CNC. No analysis, but waved again to state the "this looks cool" style response.

"Hackaday didn't get a'cut' for this article, nor did I. We don't do it. I originally planned to write a shorter article, but then I went into technical comparisons because I guessed I was a huge nerd , And then was dazzled."

I am an electrician and I don't know which part of the engineering world you come from, but there is no analysis in that article and no analysis. When "you are a huge nerd and get overwhelmed", this will make you look like little people.

I am not saying these words to disappoint anyone. I say this because the content written completely devalues ​​the content of this website. People who don't know enough will come here to stroll around, buy one of the many products that "you are dazzled", and find that it's nonsense compared to the ones there, and then never return to this website. To make matters worse, you look like a liar, and anyone with a technical background will be angry with ad-based content in the form of articles. Not only that, when you don’t even compare the content of technical articles objectively, you can’t consider the fair analysis you write. Unless the goal is to make Hackaday the next Buzzfeed, no one will care and leave.

"Thank you for your feedback. We will look into it." Maybe this is why the reply button disappeared. Again, you really only need to scroll down and see everyone who has been reading content every day for years and they are very annoyed at this point.

Hey site editor: I looked around for a link to the tag guide. Either I am blind (very likely), or the link is not obvious enough.

Just use HTML. img src works, href works, bold and italic works. This is what you really need.

She literally built things on the table. what should I do? Ask her to open and test a machine that has been in use for five years? She said it was effective, and I believe it was effective. When I have my doubts, I don't think they are worth calling her entire career. Instead, I chose to trust the assessment of another technical expert.

I understand logical fallacies, but there are also civil fallacies.

Pro tip: If you don't want to be mentioned, please don't write. I think this is no longer entirely your fault. In a large number of online and print publications, editing is a lost art. A suitable editor would simply delete these two sentences without causing any loss to the content or validity of the article (read: "The Fashionable Way of Writers Today"). Or lose the credibility of the author.

I understand to criticize any article, including this article, and I agree with the civil boundary. Remember, the comment area of ​​hackaday is the shark tank

I cannot avoid feeling that the price of this machine is too high. It's a bit unfair to compare it to those Chinese routers that cost $500-1000. For $3,000, you can buy things like G0704 (about 350 pounds of cast iron drills) and parts for CNC conversion (I mean decent parts).

I also don't understand what an impressive abgout milled PCB is. 0.006 inches is not that small, and the amount of material you remove is negligible.

However, for plastic toy factories, 6mil is quite impressive. Compared with ordinary CNC, this is of course ridiculous-there are tens of microns (~0.5-1mil).

The 6mil specification has nothing to do with the resolution or repeatability of the machine. When you get ultra-fine marks, they are really easy to lift. Remember, you are using a rotating cutter to try to remove copper from the substrate tower. Physical abuse is too much for very fine traces.

I use this machine to mill circuit boards almost every day. I have done toner transfer and amateur level lithography, and I will never go back. I have learned the quirks of using this tool to make circuit boards, and I only slightly changed my design to accommodate them. I soon have a finished board without chemicals. After the prototypes are completed, I will make them professionally manufactured. Now, when I reach that stage, they are right and I have full confidence in them.

Of course, I know this difference. The point is that the capacity of 6 million PCBs is touted as something amazing-but that's not the case.

Glad to see it useful to you, but I will continue my etching and board room. It took an hour or more to mill a circuit board the size of a Eurocard, no thanks.

seriously. I paid less than 2k for my shapeoko xxl. I know this might be better in details, but the raw materials are much less. For 2K, I got 3 heavy aluminum rails with a length of 1 meter.

I'm not sure what price it should be, but 3k is too much.

It depends on what you want to do and what uptime and support you expect from your machine. For micro-circuit board or precision milling operations that are performed every day, this is not a bad choice.

6 mil is not small enough for a circuit board! The trace itself is usually 8 million or less! Let's see what we can get at about 3K...

http://www.ebay.com/itm/Emco-PC-Mill-55-Trainer-Countertop-CNC-Milling-Machine-/191915844175?hash=item2caf13624f:g:lcAAAOSwFNZWxc44

3.5k is used for "real" things (I know, it's not Bridgeport). We should trust the manufacturing knowledge and experience of the past 200 years instead of investing in the latest start-up companies. For a long time, the manufacturing industry has been committed to solving production and cost issues.

Oh, and the last technical gold nugget, HDPE has an elastic modulus of 0.8 GPA, while aluminum is 68 GPA, and cast iron (such as the rolling mill in the link) is 130 GPA. She must have a Ph.D. other than engineering to miss this simple fact. I fully understand whether they adopt it for business reasons, but remember that companies sell a lot of garbage to make money. They obviously did not make quality their top priority. In my opinion, this is an overpriced and poorly designed toy.

– Believe me, I have a PhD in engineering (not really, I have!).

6 mils is 8 mils or less (here "6 mils" refers to the trace width). I think you confuse the trace width and the space between traces with the accuracy of the milling machine's X/Y positioning. They are different. I also criticized their design choices, but I think I should help clarify this.

About 6 months ago, I bought another mill at work. I like it very much. I have milled many circuit boards and even quite a lot of aluminum. I successfully burned the first bad motor, but the new one is great! The only thing that is a bit bad is that I want to buy one home, but I can't. The othermill pro is still in pre-order, and the standard model has been sold out. :(

If you haven't seen it yet, Danielle's presentation at Supercon last year was great-many details about implementing a quality control system using some very beautiful software tools. Looks like a great product, 6 million is impressive!

https://youtu.be/LNidIy7t0DQ

6 million is not something impressive, especially 3,200 dollars...

If it is "as good as the Ultimaker" (it is very similar), then it will be "as good" as a US$400 Chinese machine with roughly the same parts in the same location. China... $3,300! Ha ha. Yes.

As someone who deals with PHD all day-they are usually good at mathematics, but anything else they claim is an arrogant appeal to authority. You must be skeptical, but you must not show skepticism, otherwise the subtle PHD will change Get weird and yelling.

O. ... K. ... Now, where is the hacker? It's about proper engineering and elegant product design, when you have a wide selection of materials and manufacturing services that are beyond the resources of personal hobbyists at your disposal. I welcome it, but I can do nothing but save more income from my daily work and eventually buy me another factory. Isn't it a challenge? If we have money, all hacking attacks are basically a waste of time. We will become Elons Musks, not hackers.

It is a tool for people who want a small CNC that works out of the box, works well and is reliable, has simple software, and is a means to the actual production goal-not the project itself. I think this is a valuable article on hackaday, even if it does not cover an actual hacking project.

The hacker is asking the taxpayer $ to design a small and expensive cnc device, mainly using offshore components and as many open source starting materials as possible!

A hacker to be proud of!

The problem with this article is that it is basically an unmarked ad.

It omits some important details, you have to search for them on the website. The point of this article is to prove that some dubious design choices are correct. For example, there is a reason why the machine tool is not made of lightweight plastic—the weight of the machine tool is important to suppress vibration. I believe they have a good understanding of the physical principles of HDPE structure, but it is a bit unwise to fire competitors who use aluminum (or cast iron on real non-toy machines) without knowing this.

The comparison with China 3020 is also a bit small. We are talking about a working space of 300x200mm, while Othermill’s 140×114mm and 3020 also have a larger size, up to a working space of 600x400mm. Oh, 3020 is 600 US dollars *shipped from China*, and the pre-order price of Othermill Pro is 3,200 US dollars (excluding shipping). More than 5 times the price difference-smaller working volume, plastic chassis instead of metal (sorry, metal will hold shape and wear longer than any HDPE), bushings instead of ball screws (they do work, but they are one A cheap solution). For this price, I would be happy to put a RAMPS board or something in there to get rid of the stupid parallel port interface. Upgrade boards for these machines can be seen everywhere. The same is true for spindles-there are several solutions available and some aftermarket solutions. Even with the upgrade, it is still cheaper than other mills...

To be honest, I don't care that Othermill has custom spindles and custom steppers-this is actually more of a burden than an advantage. If the machine breaks down in the future, I will not be able to find spare parts except the manufacturer, and standard size NEMA motors can be seen everywhere.

You can buy a used full-size CNC milling machine on eBay for only $3,000. If you want to buy a smaller CNC and don't want to buy a Chinese CNC, then the cost of this German Proxxon is about US$1500: http://www.proxxon.com/en/micromot/24340.php

Proxxon still has a larger working volume, can fit a 4th axis, and is very sturdy-that thing can machine steel! Good luck in doing this on Othermill. In addition, Proxxon is a mature German machine tool brand, not a start-up company that will disappear tomorrow (I wish you find spare parts for the machine...)

Another option is one of Shapeokos-even the largest one, the price is still about half of the price of Othermill, and the working space is much larger.

By the way, buying very expensive desktop CNC routers to make PCBs (which seems to be their main sales focus) is just stupid. Even home-etched toner transfer boards can easily reach a resolution of 8 million, and in most cases, when the CNC finishes it, I have etched, drilled and filled the board in half. Reduce confusion (FR4 dust is *cute* carcinogen!) and noise-this is important if you work from home. The *slow* of CNC milling PCB! If you need a track/gap smaller than 8/8, then you most likely also need a solder mask-and then you have to transport it to the board room anyway. The milled PCB is mainly used to make prototypes of microwave filters, etc.-but this is not something that ordinary Joe would do.

This machine is an expensive solution to the problem, IMO.

I think Proxxon sounds great, but I can only find it for around $5,000. 1500 dollars, where did you see it?

Oops, you are right-$1500 is the non-CNC version. Mea culpa, you should look more closely. On the other hand, manual CNC conversion kits are very cheap, and there are many items on the Internet (for example: http://www.instructables.com/id/Easy-CNC-conversion-of-a -small-mill/?ALLSTEPS) Complete CNC The price of the 5k version is because Proxxon sells it with their CNC software, not anything.

No, Jan Ciger, the conversion kit you linked is suitable for the infant Proxxon MF70, not the larger Proxxon FF500. Do you imagine that Proxxon's FF500/CNC comes with "their" software? No, it comes with software and controllers from http://www.max-computer.de, and uses Chinese switchgear. The FF500/CNC vertical Z-pillar with dovetail groove is extruded anodized aluminum. Please don't imagine that German brands mean German products, or German design that makes products "excellent".

I've seen this machine since the beginning of the MIT "Manufacturing Machine" project. This is indeed an elegant idea (a fully-contained desktop, with handles, and inexpensive). I just hope they can use epoxy granite to cast the shell parts and use Slocum's design to realize self-compensating static pressure (true hydrodynamic) bearings. That would be a neat little machine-it can even attack tool steel at the appropriate speed/feed.

If you want, the Chinese toolkit that needs to be patched sounds interesting, but not everyone is interested in using half-baked tools. The advantage of Othermill is that they have a complete ecosystem. You buy a factory and the same company supports parts, machines, software, upgrades, etc. I saw the appeal and value in it, and I don't know why everyone bends so much-of course, a company that adds luster to all these experiences will have to charge more for their machines.

That's fine, no problem. However, in this price category, you can buy larger/better CNC machines (such as Shapeokos) elsewhere, or you can buy similar machines at a lower price. This is the main problem of Othermill.

There are not many types of factories that have a complete end-to-end solution to quickly cut PCBs on the same day. Maybe it's LPKF, that's all I can think of. This machine seems to require minimal training and expertise, and is just a brainless solution for rapid PCB manufacturing. Once the process becomes very difficult or time-consuming, it is no longer worth it-just order the board from the board room. I haven't used it, but I did some CNC machining, which can tell the software to abstract a lot of complexity. From handling gerbers to setting tool height and flipping the circuit board. For a beginner at a level, cutting the board looks very easy.

Shapeoko's are also great (I want a home), but they are bigger and not enclosed, they don't have software to convert PCB gerber to g-code, trim router spindles are very loud, etc. I suspect that milling PCB is feasible on Shapeoko, but it is frustrating.

Are you really aware that there is free software that can convert gerbers to gcode?

I haven't played free things recently, maybe free things are great and easy, maybe it's all buggy bullshit. Don't mind seeing someone comment what there is now.

"Based on the aluminum alloy compared to it, HDPE can be stronger than aluminum while offering many obvious advantages."

For the sake of science, how about using some units of measurement on this "stronger" statement. The ultimate tensile strength of 6000 series alloy is about 256 MPa, while the average UTS of extruded HDPE is 25 MPa, which is for reference only. So I don’t know what you mean by stronger? How strong, what attributes are you talking about?

When talking about material properties, it is best to determine the properties you are talking about and their average values.

You're right. To be honest, I can’t wait to concentrate on one part of an article. I started to make a comprehensive comparison of the materials, and then decided to oppose it. Because for any load, when operating within specifications, any machine will see two materials more or less well. I decided to keep it stronger.

What I am trying to obtain in the most constructive way is that "stronger" is a qualitative word with no empirical measurement unit. Aluminum has a higher tensile strength than HDPE, and we can measure and compare these results. HDPE has higher hysteresis and fracture toughness than aluminum, which is also quantifiable. The word "stronger" is just a marketing term and has no meaning in terms of material characteristics. I will write that line:

"HDPE has certain mechanical properties and is more advantageous than aluminum in such applications."

This will be a good guide for you on the damping part.

You are 100% correct again. Looking back now, I hope I have done it, and I will try to keep the material part of my analysis to a higher standard in the future. Thanks for your feedback.

I know some people won’t like this statement, and it’s not 100% specific to this matter...or you don’t have to get one but...

When did the hacker mainstream develop? When on earth do we give up real hacking together and rely on other people to build dedicated machines for everything we build? When will we become a common market and everything we buy needs to be turned-key (I know that turn-key is not actually applicable, I am not an English-speaking hacker)? What happened to buy crappy stuff at a cheap price and make it better?

Okay, sorry (not really) this is my rant

On the contrary, most people in this thread agree with you, just with less polite words.

The Othermill was very immature in the beginning. I think hearing about unconventional design choices (casing, HDPE frame, etc.) is an interesting material for other hackers' creative process.

Agree with you, cool product, although a bit expensive, but I think I am just dissatisfied with the switch to hacking toolboxes that contain unnecessary high-end tools.

Finally, I checked that no one has a monopoly on the word "hacker" or the level of abstraction at which "hacker" must work.

You want to buy a pre-made arduino board and integrate it into your custom wireless thermostat. This is a trick. You want to build a custom arduino board with your own AVR chip flashed with the Arduino bootloader. This is still a hack. You want to run Arduino code on a Softcore AVR CPU running on an FPGA that is still a hacker; no matter what level of hardware (definitely software) abstraction you are working at.

If we have to build everything from scratch or use incomplete tools, then our ability to build cool things will be limited. MacGyver is a very neat show...but it's not true.

You take this back, MacGyver is a true hero and source of inspiration for all of us. :-P

I think it depends on how you choose to spend your time. Have you built your own: CNC Oscilloscope Soldering Iron Wire Drawing Machine Ore Smelter Some people need CNC as a tool for the task they want to do, and would rather buy it than build it. It's fun to check the toaster project when you have time.

Not a hacker. More like an advertisement. Please resume hacking.

I don't know what all the commotion is about. I don't know much about CNC machine tools, nor do I understand the advantages of CNC machine tools made in other factories and China. But I noticed that more and more people are willing to "cheap" and buy the cheapest arduino clone/breakout board from China, even not considering buying a slightly more expensive board locally. A typical example is to consider buying STM32 bluepill for $2, rather than better support for Teensy3.0 for $18-20 or Nucleo board for $11; the first to support Paul.. an amazing engineer who made The vendor/Arduino community has made many contributions, and the second one directly supports the manufacturer (ST), which makes affordable and easy-to-use circuit boards.

This is not nationalism, nor is it the worship of the flag, founding fathers, queen, and country. This is mainly to support local businesses so that we have a strong local economy that ultimately supports us. Let's face it...Globalization has failed us. We don't do anything anymore! ! ! ! Nothing at all! ! ! ...Except weapons, burgers and pornography...all of these are usually harmful to you...at least in large doses.

Now I am not saying that affordability and cost-effectiveness are not an important factor... but it is foolish to make it the only factor, and it will only encourage a market full of cheap garbage. Even Chinese manufacturers will eventually have to further reduce the quality of their products to meet the prices that consumers want or think are appropriate.

I think we need to re-examine this "cost is the lowest common denominator" purchase method, whether it is for CNC machines, 3D printers, Arduinos or toilet seats.

Some things that we should consider when buying engineering products include (in no particular order).

1- Reliability 2- Supplier/ Distributor Support 3- Documentation 4- Availability of Alternatives 5- Transportation Cost 6- Supplier Proximity 7- And Affordability

I think this is a good strategy. If you disagree, please feel free to criticize it constructively. Please be gentle.

Why would anyone pay more to the distributor for the same product?

I never mentioned paying more to distributors for the same product. My point is that we need to be willing to pay more for official and innovative products such as Teensy 3.0 or Teensy LC or nuclear circuit boards, instead of encouraging the use of cheap Chinese clones/communities in the long run that will ultimately not help our economy ..

I can't stand resellers/distributors who buy arduino clones from China and then upsell them.

"The cost of Othermill Pro is one-third of the price of an equivalent LPKF machine, and it has the same features."

“It’s hard for amateurs who stumbled upon Othermill to understand why it paid such a price. Ebay is one-third the price of 3,020 CNC milling machines from China. Why would anyone give up the extra cash”

For reference only, the total price of Othermill is more than 3 times that of cheap Chinese factories, while the cheapest model of LPKF has better features at less than one third of the price. Maybe this requires more work, but publishing the feature sheet you are comparing will reduce the irony in the comment section that you claim to hate.

For those who don't know, LPKF has multiple functions that double the machine's functions beyond the scope of this small mill. Automatic tool replacement, through the creation of holes that use vacuum and ultraviolet light to pull conductive paste, error handling instead of just error messages, etc. Even though some of these features require additional cost, the fact that they are available is valuable.

I have reviewed all the PCB creation options for work, but still can't find the value. Projects with a short design cycle can easily be satisfied with the overnight PCB rate passed to the customer. Design engineers usually have downtime in terms of code/package/interface/etc, and are making circuit boards anyway.

For amateurs, the price is too high. As the founder said, she realized that her market is universities, where the people who pay are not the people who use the product.

Personally, I will never spend so much money on a CNC router for a circuit board.

But... those 60/40 or any machines made in China are nonsense! You can't repair and "repair" them, the coating is too thin and the bearing is too weak, so the first step to "repair" it is to go through it in the trash can! ! ! That being said, they *may* only apply to PCB/plastics.

It may depend on where you got which one. They come in many variants, and some even have ball screws and lathe chucks/extra shafts installed. Most people don't have any problems with their machinery (unless the machine is beaten during transportation), more electronic devices are definitely "old school", and some of the available spindles are terrible.

On the other hand, these small CNCs are sold as engraving machines for a reason. Aluminum with low feed rate will be its limit. I have watched some videos of people trying to process steel on it, but this is really pushing it. Most people buy them to make plastic and wood, so the structure is good enough.

I have a cnc3040 high-z with a ball screw, a 4-axis controller (parallel BoB), a 4-axis lathe chuck and a 200w spindle with a flexible shaft. The price is about 850 euros, including delivery to my door within three days .

Yes, the terminal switch and wiring of the touch probe must be done by yourself, even ground the AC control box and tighten all screws. But after a few hours of intensive work in the past two years, I am generally satisfied. Some parts are worn out and need to be replaced/optimized. From the first second I opened it, the 200w spindle is nonsense. It was painful to hear its terrible loud voice. So I am very happy that the bearing is broken now, so I have a reason to replace it with a 0.8kw water-cooled VFD spindle. I have been laying it for about a year. And the loose wires of all motors will not last long. I have some coordinates and one of the axes has lost steps. They will be replaced by cables of sufficient quality (Lapp ÖlFlex). The parallel wiring board will be replaced by PoKeys 57E Ethernet motion controller and mach3 together. Maybe it will be a better machine at that time, about 1,200 euros. PCB isolation milling is not suitable for fine pitch smd ic packages! I tried a lot, but I have given up. My old spindle has a big speeding. But I drilled my double-layer board, grind out the outline, and then use UV dry film/etch/solder mask. Before ordering my router, I have read a lot about these cheap Chinese routers. All the existing problems and some of the problems that users are aware of, so I know that some work and money need to be invested. I hope my hobby is cheap and working on the machine is fun. Most of the time I use other grinders to grind larger parts.

Therefore, when I have a larger budget for milling commercial pcb prototypes, I will not choose other factories. For 3-5k Euros, a robust machine equipped with an automatic tool changer has enough possibilities.

Compared with aluminum, the CTE of HDPE is very bad. I know these SF hipsters think they are smart, but no one else uses HDPE to make CNC machines for a reason...

What an expensive pile of nonsense, you can buy a real CNC milling machine from Tormach for a little more money,

It is worth noting that their co-founder, chief technology officer, and most of the core figures behind hardware design left the company last year.

https://medium.com/@mikeestee/confessions-of-a-hardware-startup-b9ca02b01453

From my reading of it: it is a clever design, but it may not scale well, and one of the key people who built it no longer exists. Desktop CNC is a difficult problem to solve, I think Othermill is definitely not the answer. However, I think they have done a good job for this industry. It is only a matter of time before other people release better products that are worth buying based on their ideas.

What you get at the same price in Germany. Not assembled, but the spindle, motor and controller are still $800. http://www.sorotec.de/shop/CNC-Portalfraesen/compact-line/Compact-Line-Bausatz/Portalfr-smaschine-C-Line-0403.html 2500$

What can it do (larger size, same model) https://www.youtube.com/watch?v=ZO2uw3S_tdk

– I have nothing to do with the company, I just think they do a very useful and great machine =)

– Just to point out that the linear bearing and the rock-solid aluminum frame in the price tag related to the size should be standard.

Gerrit, you realize that you can buy a parallel port add-on card for your PC, right? It is even a recommended option to avoid blowing up one that may be part of the motherboard. According to what I read on the mailing list, the work of the LinuxCNC staff related to building production machines is really like a small Intel board. I believe it is D525 with integrated parallel port.

Ah. Although now I think if you want to make a machine kit or Linux CNC, then one of the shields customized for raspi or beaglebone is the way to go.

After completion, the price of my 1990 Acra CNC knee grinder and 10×50 inch workbench will be close to $0. I bought it at a cheap price with dismantled "old-fashioned" electronic equipment. Strip off and sell all of them.

This is a factory converted to CNC, so there is still a bunch of useless CNC parts in the head. When I closed the variable speed drive for rebuilding, I stripped the excess parts from the head and sold them. Drive reconstruction only cost me 100 dollars for belts and bearings. Not cheap rubbish, I just buy high-quality brand-name parts at the absolute lowest prices on Amazon, eBay and other websites.

Motors, drives and power supplies are where I want to go, and they are cheap. They work, and they have greater torque and speed capabilities than primitive, huge, high-voltage DC motors. But the controller board is from Mesa. This slightly offsets the profit from the sale of removed items.

If anyone wants to make the best* desktop CNC milling machine, please restore the old Light Machines PLM2000 design. (It was manufactured by Intelitek for a while after they acquired Light Machines.) It has an epoxy granite frame, uses circular, fully supported rails, and has linear bearings on the bed and headstock. I paid $2,000 for one of my spare dealers, which is very cheap compared to the price they usually sell. Since I was able to get someone from Moog Animatics to root in some old computer backups, and I have technical information about the servo controller, I should be able to get Linux CNC to run it without having to use the old MS-DOS software. The stepper motor PLM1000 has Windows software, I don't know why they have never done it for the servo motor PLM2000. What makes a PLM factory an excellent factory and is still highly sought after? quality. The mill weighed nearly 400 pounds. They have a working load of up to 100 pounds. There is no such high-capacity factory on the market. There are some smaller factories, but the production capacity is much lower. There are several sizes that are close to the same, but although they are all metal, they are lighter and cannot move under a load of 100 pounds. Then the next jump is that the machine is too big to be considered a desktop machine.

Then all the parts built around Sherline parts. They are only suitable for small projects, but can be very precise on small projects. The prices of some CNCs are ridiculous and higher than the commonly used PLM mills.

But wait! There are crazier higher prices. The basic price of the aluminum frame rolling mill produced by Minitech is US$12,000. Then you can add CNC systems, spindles and other options. However, they are made of a large number of 3/4" aluminum plates and double THK linear guides, 4 blocks per axis, and very high-precision ball screws. They are still much smaller than PLM, especially in terms of spindle capacity. I know one that has People from Minitech Mini-Mill/3. He wants to sell it, it’s too small. Only $1800. I have an old Flashcut system, and I use a computer old enough to run Windows 95. Why? Because Flashcut owns ( Or it will be owned by anyone) The only software that supports the 401A box is 16-bit and can run on Windows 3.1, but 95 runs Win 3.1 software better than Win 3.1.

Or how about Emco F1 CNC milling machine? The table is smaller than PLM, and the load capacity is not so high. Original equipment steppers are terrible, with only 75 steps per revolution-but they have a very sturdy headstock, a powerful motor and a #30 taper capable of using industrial tools. Most F1 car owners have upgraded their stepper motors and electronic equipment, and their mills are better than any similar products currently produced in terms of size and capacity.

Put the #30 taper spindle on the copy of the PLM, this will be the ultimate skill of the desktop CNC bed milling machine.

Those light machines are great. I want to say mechanically, EG is something very cool.

"But it's almost entirely made of parts sourced in the United States." Oh, yes, overpriced hardware made of condor beaks and gun parts. Out of principle, I will take anything from China at any time, not from the United States.

I want to know why it is compared with CNC3020 ($500), while the price of other mills ($2000) is in the range of CNC6040 ($1500). For example, CNC6040 spindle is much better than CNC3020, and its working area is much larger than other milling machines.

Hey-is this another factory based on MIT's MTM work? look alike

Yes, it does. If you go here you can see the evolution (scroll to the bottom of the page): mtm.cba.mit.edu. The MTM project really gained attention in the 2009 Neil Gershenfeld's "How to Make Almost Anything" course. Around that time, Jonathan Ward designed the MTM AZ, and then together with Nadya Peek developed the MTM Snap on which Othermill is based. To be honest, if other machine companies recognize this tradition somewhere, it might be good.

Forgot the ":" in the link... mtm.cba.mit.edu. In fact, there is a thank you section on the Othermill website with the names of hundreds of Kickstarter supporters who "helped to build" the company. Not to reduce the contributions of their supporters, but if this is a barrier to recognition, I think they should mention Jonathan Ward and Nadya Peek, whose open source work has made such a critical contribution to the company.

I would rather own a vertical mill from the 1950s

http://i1.kym-cdn.com/photos/images/newsfeed/000/181/932/tumblr_ln5lgh9OPi1qd8gt3o1_500.png

It’s really frustrating to see the number of professionals spreading misinformation and so-called SEO professionals

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