Freesteel Blog » 2008 » January
Just before new year I was in Berlin for the Chaos Computer Congress. The video-casts of that event are finally coming on-line here, or, if you don’t like that, you can pick from this chaotic list of about a hundred conference recordings, where they don’t tell you which ones work.
I got featured in a podcast by bicyclemark — which I’m not going to listen to because it’s my own voice, which is even more excruciating to me than reading my own writing — that I’m told is not bad. I also showed my undemocracy.com site at a lightning talk, which is not on-line. Maybe I have to trawl through the hundred unofficial recordings to find it.
I did see some very good talks at the 24C3, which I can share with you from the list:
- Open Source Lobbying, tips from the trenches – From one angry e-mail to writing national policy on open source – The campaigners in the Netherlands won the case outstandingly. It’s very important to build up a dossier of irrefutable facts that are easy to digest by politicians. They want to share their materials, which are available here.
- The Arctic Cold War – bicyclemark It’s a 45 minute talk (don’t waste your time with the questions) about all the military hardware being moved into position by Canada, Denmark, Russia, etc, and the shenanigans over each country attempting to claim the polar sea according to the shape of the continental shelf, and this business about planting flags by submarine. To get the spirit, check out this long wikipedia article about a rock between Greenland and Canada.
- It was a bad idea anyway – The demise of electronic voting in The Netherlands The performance is just as bad as in America, but without the gratuitous complicity of the government using it for political power. It’s a catalogue of jokes. The speaker said: “You can laugh now, but your government (Germany) is bringing the same companies here.”
- What is terrorism? – And who is terrorising whom? – A talk by blogger whose husband has been picked up by the German terrorism police and is being subject to a state of unreasonable intelligence surveillance. This too was a complete joke, except for being real.
Those are the main ones that spring to mind. I might trawl through and list some other that were good, and watch the talks I didn’t mean to miss. Maybe I can go through the videos of the conference next year and not need to go. Howzat for using the internet to reduce travel, rather than as a tool to find yet more travel opportunities you would not otherwise know about.
What we need is to hold a post-ghost conference where you get a bunch of friends for two days and watch all the videos hourly on separate screens according to a strict timetable and discuss what you’re seen while having a beer in between sessions. You sometimes watch the same thing, or different things.
The groups who do the ghost conference before you can thin out the crap so when it’s your turn you get all the best bits only, and all the talks are outstanding. You could arrange to have the speakers on-line at some point during the day through their Skype connections and take questions.
I want to see people arranging conferences as a visual unit. Maybe the talks of the past three chaos conferences could make one kick-ass day long sessions all perfectly programmed on a timetable because you know what they are like now they are recorded on disk. Then we hold it, much like those Star Trek festivals where it’s every episode back-to-back over 40 hours. Same deal, but with conference material. If it’s worth travelling to, it’s worth doing this.
Tuesday, January 22nd, 2008 at 6:03 pm - Machining
Right, I’ve been at this algorithm continually since before I went to Euromold at the start of December, and I’m bored now. It doesn’t crash. It runs twice as fast. It now has the capability of operating in parallel on multiple processors — which I thought it did before, but I had made a mistake.
There’s still lots of cruft, unnecessary functions, code that needs to be cleaned out, and improvements on the fact that, in the pictured example, if doesn’t operate perfectly when two sides of the collapsing toolpath appear on the same vertical wall, but who cares? This needs to a major rest and reprieve to collect some further bugs.
Meanwhile, our colleagues are at SolidWorkWorld showing off the new Solid Gold Star Partner Solution Product HSMWorks. The other two Golds in the sector are called SolidCam and CAMWorks. All we need now to complete the picture is a new product called “SolidHSM” which, for the sake of symmetry, would have a similar performance. Later, a Chinese hacker would merge them all together into one single categorically superior multi-kernel system called “HSMCam” which everyone could download for free but didn’t because they preferred to use MasterCam.
There’s a SolidWorksWorld podcast, which I have now downloaded. I wonder what it’s going to be like to listen to.
Our out-of-his-depth Prime Minister, Gordon Brown has hit the news with his support for permanent membership of India on the United Nations Security Council:
Britain is pressing for the Security Council’s five permament members to be increased to include India, Japan, Germany and Brazil, plus an African country. Diplomats refused to say which, for fear of offending the chief contenders: South Africa and Nigeria, both regional powers, and Egypt, which is backed by Arab states. One possibility is a permanent African seat rotating between three or more countries.
Under Mr Brown’s plans, the new members would not initially win veto powers similar to the existing five – the United States, China, Russia, Britain and France. Instead, places on the Security Council would be offered without blocking powers in a first phase, followed by subsequent changes that included veto rights.
The Ambassador from India spoke at length on the subject last November, referring extensively to the book, Surrender is not an Option (Defending America at the United Nations and Abroad), a recently published tome by John Bolton that has had rave reviews from the forces of war.
There are many intelligent things which one can say about the dysfunctional workings of the Security Council, but none were said during those three days of debates.
The first thing to note is that the Security Council is the single body whose resolutions have the force of law regarding war, peace, and international economic sanctions. It is within the treaty obligations of the United Nations that members must respect the Chapter 7 resolutions passed by the Security Council.
Obviously, certain powerful nations with their “manifest destinies” aren’t going to put up with this type of thing, and have negotiated an exception to this rule for themselves. If there is any resolution about to come out of the Security Council which they don’t like, they can strike it out with a unilateral veto. Even if they are in a minority of one, the resolution will not pass, which makes them safe from any ruling. Technically, a nation with this veto power must be on the Council at all times, otherwise the world would merely have to wait until they were rotated off to pass any sanctioning resolutions against them. That is why they are known as “permanent members”.
The veto can also be used to prevent resolutions that “determine the existence of any threat to the peace, breach of the peace, or act of aggression” by an ally of the permanent member. That’s why Israel doesn’t violate very many Security Council resolutions: the United States vetoes them out of existance. Remember that when the next politician proves that Israel is more peaceful than Iran by counting the number UN resolutions against the respective countries. The judge is demonstrably corrupt. A raw count of the disproportionate attacks on neighbouring states gives a better picture. After all, it’s those which draw blood, not the resolutions in condemnation.
We can be pretty clear that had Iran been a permanent member of the Security Council, no resolutions would ever have been held against them. Iran was an ordinary member of the Security Council in 1955-56. In case you’re wondering what democracy has to do with the Security Council, their CIA backed coup d’état against their elected government was in 1953.
The five permanent members of the Security Council are: China, France, Russia, United Kingdom, and the United States.
In the meantime, there is another important component of international law known as the Nuclear Non-Proliferation Treaty, which makes it illegal for all nations in the world, except for five, to develop or possess nuclear weapons. These five nations are: China, France, Russia, United Kingdom, and the United States.
Clearly, as with United Nations Charter, at least one these five nations doesn’t feel it confers any obligations upon it with regard to disarmament. And another openly flouts the letter of the treaty which in Article III (2), says:
Each State Party to the Treaty undertakes not to provide: (a) source or special fissionable material, or (b) equipment or material especially designed or prepared for the processing, use or production of special fissionable material, to any non-nuclear-weapon State for peaceful purposes, unless the source or special fissionable material shall be subject to the safeguards required by this article.
Those safeguards are embodied by the IAEA and the Non-Proliferation Treaty.
And this is where it all comes full circle. The equivalence between the Security Council permanent members and the nuclear states is not an accident. Only three nations did not sign up to the NPT: India, Israel, and Pakistan. (North Korea withdrew in 2003 during the process of its largely irrelevant political narrative.) Israel, for all purposes, already has the representation of a permanent member. Pakistan built their bomb in response to India and is in record that they would disarm immediately once India does so. Which leaves India as the main front for nuclear proliferation. As a government official once explained
No-first-strike’ policy does not mean India will not have a first-strike capability.
So, what’s the conclusion?
I don’t know. I am not a professional journalist with access to politicians and in a position to bring important questions to the public’s attention, but choses not to. Questions like:
(a) Is Security Council permanent membership simply a nuclear club?
(b) Would India be willing to trade its illegal nuclear weapons for its permament seat, or is the world offering it for free?
(c) Why does the world need the UK on the Security Council at all?
Sometimes it’s hard to believe the Cold War actually happened, with all this continuing military build-up and mass threats of nuclear-death. It seems as if the process doesn’t require an terrifying enemy to stimulate this reaction — our dysfunctional political class seems able to prepare for armageddon all by itself. They’re clearly insane.
On the other hand, one wonders what the hell is going on inside the minds of the engineers who are still devoting their lives to putting these bombs together. Are they doing it only for the money? No way can they believe what they’re doing is helping the world. What do they think they’re doing?
-  Gordon Brown supports permanent seat for India on UN Security Council, 21 January 2008, The Times.
-  Mr Sen (India), 13 November 2007, United Nations General Assembly.
-  Screw The U.N. (before they screw you) blog, 3 January 2008
-  1953 Iranian coup d’état, Wikipedia.
-  Brown backs Trident replacement, 21 June 2006, BBC
dunno what technorati is, but I’m s’posed to include the following text into a post:
Friday, January 18th, 2008 at 5:50 pm - Whipping
I have reported before about the awesome debacleness of UK government computer projects, but I never known why it had to be so bad. Now I’ve seen a clue in the response to an FOI request about the “future development path for Parliament’s Enterprise Architecture”.
-  Look what I found looking for more info on the e-Envoy, 27 November 2006, Freesteel blog.
-  PICT agreed set of priorities and programme of work for the period up to 2009/10, 17 December 2008, FOI archive.
This document is one of the worse I’ve ever read. Everyone who’s seen it has had their brain scrambled. Here’s a sample
PICT Priority 2007 – Performance optimisation
Objective: to establish efficient and effective service management within PICT to identify and reach external benchmark standards of ICT service provision, and provide capacity and capability for sustainable ICT within Parliament This work will include:
- the development of definitions of Requests for Change (RFC’s), and ITIL based processes relating to requests for change
- working with Gartner to establish ITIL compliant process and practice in problem and incident management, developing benchmark performance targets and establishing activity to achieve these across PICT directorates.
- the development and use of the ITIL Service Management Toolkit processes to monitor customer experience proactively
- developing KPI dashboards as a management tool, and for monitoring performance targets across PICT directorates.
- knowledge transfer across staff for more generic working (to include documentation management and configuration management)
- developing a culture of matrix working (sharing responsibility for service levels across PICT directorates) and managing the interface between network, servers and applications
- developing and implementing a 24×7 support service
And I’m wondering, ITIL?
Aparently it stands for Information Technology Infrastructure Library, for which the UK government claims the credit. The Wikipedia has been infested with cruft about it, but there is one very short quote at the bottom of the article:
ITIL manuals are like kryptonite to enthusiasm.
- Service Strategy
- Service Design
- Service Transition
- Service Operation
- Continual Service Improvement
When I saw this, I recalled something from that brain scrambling document. Chopping out everything but the headings, we get:
Our strategy is to develop and improve our capability in the core areas which we believe are necessary for us to deliver what Parliament expects. These core capabilities are summarised under Objective 5. At the same time we aim to make tangible improvements in our service within a broadly neutral cost framework. Performance measures and targets are included in the plan.
Objective 1: Improvement of Infrastructure and Desktop Environment
Objective 2: Architecture and Applications Delivery
Objective 3: Improving Members’ Services
Objective 4: Improving the Customer Experience
Objective 5: Improving PICT’s Use of Resources
Yes I know they don’t match up with the core texts, but there’s a sense of an echo. Each heading is divided into two parts called “Context” and “Aims”. For example, the “Aims” under Objective 4 are:
PICT Performance Optimisation Programme specific include aims:
- Service Best Practice
- Service Standards (ITIL based)
- Service Knowledge
- Service Performance
- Service Response
- Service Flexibility
- Service Integration
- Service Expansion
This development will be initiated in 2007-08 in a structured ‘PICT Performance Optimisation Programme’, consisting of focussed projects in each area. Each project will consist of key stakeholders, process owners and implementers, made up of PICT staff, and will be managed to agreed timeframes with high quality risk, communication and change management.
The PICT Strategy Board will approve proposals, changes and govern progress. Developments are planned to continue into 2008-09.
It’s important to read bits of this document out of context to appreciate the awesome futility of life that it represents. The words leave you with nothing; no questions, no comments, no arguments that you respond with. It’s a work of abstract poetry.
Here’s a couple more snippets:
independently of the organisational context, ICT moves on with new opportunities, new skills required, new ways of doing things better
people work best when they are well matched to the tasks in hand, neither uncomfortably overstretched, nor feeling under-challenged
What can one do now? One of the problems is that the writing and design of the UK government software is often contracted out on what is a basically cost plus basis. No one loses money. There is no incentive to produce anything that works. This ITIL system gives the appearance of progress all the way through to the end of the project when the big chicken finally lays an egg, and it turns out to be full of dust.
At the bottom of it all, these projects are supposed to produce software that works. When the government contracts a company to build a school, you expect to see some construction works on the ground at half-time. The visibility of it keeps the process somewhat honest. If the owner doesn’t know what’s going on, he can hire an independent experienced builder to tour round the site and check that it’s all up to scratch.
A good move would be for all Government IT projects to copy their code onto a public server, like it was a building site with peep-holes through the barricades. Then we could glance at it to see what was happening, and if any work was actually being done. The code, ultimately, is final the result of the project, once all the organizers, accountants, and designers have walked away. There’s no reason we shouldn’t see the work in progress.
This press release about the winner of Mori Seiki’s Cutting Dream Contest (news inexplicably released from “Gloucestershire, UK”) cites WorkNC as the CAM system of choice by Kawanami Ironworks of Kyoto for cutting their amazing metal jacket.
So much for my recent rant about what appeared to be the effects of WorkNC system in Berlin.
The engineer responsible at Kawanami Ironworks explained the process. “The model was entirely made up of free form surfaces, so the most difficult task was planning the sequence of operations and positioning the job datum.” The ultimate aim was to produce a finished product which properly represented the look and feel of the jacket. He continued, “The majority of the part was cut with WorkNC’s machining between two curves strategy. We found that this gave the best result for expressing the softness of the fabric.” Kawanami Ironworks’ engineers also used many of the other finishing toolpaths in WorkNC, these enabled them to pick out the fine detail and access confined areas without tool or holder collisions.
I stand in awe. However, this is clearly in the 5-axis department. I am a 3-axis expert, although getting a bit tired of it now. Eventually I will get all the programming I need done and then I can move on. 3-axis is special because there is no more than one cutter location for every point on the model. This means the field isn’t endless because the basic algorithms and geometric structures on which everything else is built can be counted on the fingers of one hand (even if the most fundamental one is generally overlooked by academic study). 5-axis has two degrees of freedom for every point on the part. This makes the whole business a lot less obvious.
What’s missing is a good video on youtube of the winning entry. WorkNC, at least, has some videos of small operations on their webpage. (Not all of them impressive, but it’s moving in the right direction — video is the natural media for promoting these products.)
Their Digital Technology Lab (DTL) in California has…[link]:
pioneered in proactively working with the following CAM software vendors in helping them develop post processors for Mori Seiki machines. Through this collaboration our mutual customers will now be able to get reliable post processors as soon as they purchase Mori Seiki machines, hence jump starting their productivity. Working with several top CAM software vendors enables our customers to choose the CAM software(s) of their choice and be able to fully utilize the machines. DTL provides post processor specifications, requirements, testing and consulting support to the CAM software vendors. DTL also provides assistance in creating realistic machine solid models to our partners, so they can build Machine Simulation solutions as an added benefit for our customers.
About time too, I’d say.
The history of post-processors, in my opinion, encapsulates everything that is wrong in the CAM industry. There is virtually zero communication between the machine tool manufacturers and the CAM software developers. The language accepted by the machine tools has never been successfully standardized, and continually forks. And the machine tool manufacturers do not take any responsibility for the chaos they have created.
Contrast this with printer manufacturers who will distribute printer drivers for their printers and your operating system without any questions. There are thousands of them. I’ve never known why they can’t all use the same driver since they all do the same thing with the same input, so why not put the transformation which specializes it to the hardware in the printer itself?
With machine tools, the CAM system supplier has to build the post processor to drive the machine. You can phone up the manufacturer, but the most you will get is a copy of the manual documenting thousands of features you never need to use. No working code. Nothing.
So usually in the CAM company someone who doesn’t know anything (for example: me) botches something up to replicate the look of a file which the customer has supplied until he is happy with it. Maybe it sets the feedrate on every single line, or just when it changes. Maybe feedrates are on their own line, and rapid motions are programmed with G0, F9999 or FMAX, you never really know why. But as long as the customer is eventually happy, you never know if he’s losing 15% of the efficiency of the machine because there are too many unnecessary characters and causing block starvation. Amazingly, we heard problems about how machine tools stalled creating marks because it moved faster than it processed the motion instructions. Given that the machine is always varying its speed to go round corners outside of the control of the instructions, why couldn’t it slow down a little to avoid this stalling? Why couldn’t we get a warning? We were in no position to debug it. Usually it needs lots of points to go round corners, so should be going slower anyway. As the speed of processors was increasing faster than the speed of the machines, we ignored this problem and hoped it would go away.
I wrote the postprocessors at NC Graphics for six months before I even saw a machine tool. Even today there’s a man who makes a living by writing post-processors from scratch. Post-processors should be the first place where open-source software gets a foot-hold in this industry. Machine tool manufacturers should write them, distribute them, and maintain them to encourage best performance from their machines.
Mori Seki has a page explaining the status of post-processor development for each CAM system, eg MasterCAM. Unfortunately these link to the CAM vendor’s webpage rather than to a direct download. They seem to be reluctant to step on the toes of the CAM software suppliers. They say:
Mori Seiki or DTL do not recommend any CAM software in particular and it is up to our customers to decide the best choice for their needs.
Why! What are they afraid of? Why don’t they do some benchmarking and give us guidance so that we know which parts of our software are substandard, and which parts are great? Nobody has any idea.
Short record of weekend.
After seeing Ringo Starr sing out of key from the roof of St George’s Hall in town, we drove to Yorkshire where I sat around in Bull Pot Farm till the not-so-wee hours of the morning around the fire with Johny Braindead and had too much beer. He explained how he took his car insurance company to the small claims court one day and won. The process sounds like it could be straightforward enough to work, should I have the cause to use it.
In the morning I had a disproportionately bad hang-over, went caving down Wretched Rabbit in Easgill following Becka and MG to a place near Top Sink for some surveying. I collapsed in a miserable heap for a few hours while they continued on. When I got too cold I started throwing up. It was one of those “I’d rather be dead” days.
Uh? What in earth is going on over at one of my favourite CAM software companies?
New venture for Vero
The company believes that there is a new market in the provision of a graphically enabled Business Intelligence tool that can analyse and present unique insights into very large sets of data. To that end it has licensed the leading data mining solution Mineset… Don Babbs, Chief Executive of VI says, “While Business Intelligence tools have become the norm for the financial and consumer markets the value within the ever increasing data belonging to the manufacturing industry has been largely overlooked. The formation of an experienced data mining team together with our source code applications based on the renowned Mineset engine will see the start of a process allowing manufacturing and industry users alike to unlock the benefits of their data collection systems.”
Deployed network bandwidth grows 3X annually – suppliers and users can’t track all security threats or optimize efficiently. Cyber-terrorism has increased 50% in the last year.
Due to Mineset’s unique ability to manage and visualize vast quantities of data it has become an ideal tool for detecting Network Intrusion:
Network intrusion or ‘hacking’ is a common element of all networks, whether it is malicious or simply just for fun, as is often the case today – it still presents a massive threat to organizations. An article in Network Magazine in May 2002 highlights the potential for not only the immediate cost of a network outage from a ‘Denial of Service’ attack but also the attendant bad press, dissatisfied customers and business partners, and furious executives.
Me, I can’t see anything here that can’t be done with VTK combined with some nimble Python scripts, but not everyone can program.
Sure, you can throw up 3D splatter plots of grand and pointless consumer data, I mean, if the parameters are things like engine size, fuel consumption, acceleration, consumer spending over time by gender and age, the likelihood of having callerid for the various groups such as age, occupation and type of car driven, then this is not exactly going to get us to the future.
Meanwhile, the world-famous visual data animation demonstration is a system known as gap-minder, as demonstrated by this presentation here:
So, given that this is a well developed field, with all its own foibles and plodding development in interesting directions, but with no obvious connections to CAD/CAM whatsoever, why on earth is Vero having anything to do with it? After all, it was dumped by SGI a few years ago because it didn’t fit with their business.
Now, the drive to Camtek, recently acquired, was pretty short too, but at least it was in the same business. Who knows what the rules of business are. Maybe when it’s too difficult to buy up companies in the sector internationally, you simply grab random ones that are in the immediate locale. Who am I to argue with this world? The customer is always right.
The glove box is to give it a good washing. Because it’s not possible to levitate parts of the model above the base, it’s necessary to lay down support material under the over-hangs. In this case it’s a different type of plastic whose residue can be washed off after it is peeled.
These models are for use in some of Becka’s haptic psychology experiments. To the extent that you can identify objects by their shape when you fondle them with your fingers, suggests how you might represent them in your brain. After all, it’s not surprising you can recognize a small horse in a photograph, because often the animal stands far away and doesn’t occupy much area on your retina. However, if you can recognize it’s a horse from a piece of plastic in the palm of your hand that is in no way similar to the size of a horse, then that tells you something else.
While in Tuebingen I did get a chance to witness the most outrageous machine ever, which is being built in this room of the Cyberneum, next to the other room with the big shiny robot arm that seems to serve no other purpose than to fling people around. (I seem to remember some discussion over how to program that robot to make sure that it could never move through a position where it would mangle the human against itself.)
What was being built was a 2-way conveyor belt.
Sadly, I didn’t have my camera with me. But if you can imagine a ten metre long powerful conveyor belt that’s strong enough for a man to walk on, and then stack about 50 of them side by side on rails so the whole chain can wrap round underneath, you have the picture. It’s ridiculous; there has to be a better way of doing it (they tried using a floor composed of ball-bearings, but there was too much friction).
So, that’s the state of Virtual Reality technology today. It’s worth doing it once, just to see if it can work. But all those cyberpunk lost-in-VR SF stories are now looking as quaint as the let’s travel to the Moon stories did when the first thirty storey high Saturn V rocket rolled out onto the launch pad. Since then, gravity has gotten no less, and the energy density of liquid hydrogen has gotten no more, so the reaction is still valid even if there are idiots who forget it.
Here is a detail from the base of the ten metre tall metal sculpture Rolling Horse by Juurgen Goentz (2007) on the flank of the Berlin Hauptbahnhof exhibiting atrocious machining on its the panels, including a full cutter gouge where the tool appears to have been buried 5mm into the surface.
Possibly this was in preparation for clearing the next level, which didn’t happen. Normally you helix down, because this type of plunging motion is liable to break the tool, I am told. Nobody I have shown it to thinks it was left on purpose; there is no artistic appeal here.
The rest of the motion looks like an offset clearing strategy with extra segments in the acute corners to knock off the upstands. This is a pattern I have seen on WorkNC. I should have measured it carefully or taken a clearer picture. Whenever you offset the clearing passes by more than half the diameter of the cutter, you create the possibility of leaving triangles of uncut material at the corners of the contour, depending on how big the offset is. The uncut areas are usually triangular with one side being a concave arc, like the area of unpolished floor in the corner of a room that a circular floor polisher cannot reach.
In this example, the offsets look pretty close to the diameter of that mis-cut hole.
On Machining Strategist, Depocam, HSMWorks, and any other machining kernel that I have had something to do with, the offset Z-clearing strategy checks along each contour, measures the angle of the tightest corner, and offsets the next pass appropriately so as to clear all the material. This means that when the user specifies the step-over, they have to set a minimum and maximum value so that the system has a range to work with. The defaults are minimum = 50% of diameter, and maximum = 90% of diameter. Sometimes there are full-width cuts, which are unavoidable with this strategy, but as long as the minimum is never more than 50% (it won’t let you set it to more), it will clear everything.
This sometimes annoys users who want to give a definitive large value for the step-over and not be troubled with this geometrically compromising min and max nonsense. You will find in the user manuals — particularly for versions of non-MS/Depocam software from five years ago — advice on how to set the absolute offset for the clearing strategy. Users want to set it as high as possible to get the job done in as few offsets as possible, but if they set it too high they run the risk of leaving behind these upstands — and it will be their fault because they picked the number.
If you have a rectangular area whose corners are right angles, my calculations say you can go up to 85.355% of the cutter diameter before you get upstands, because that’s equal to 0.5 + 0.5 / sqrt(2).
The next best thing to choosing the appropriate maximum offset to avoid any upstands (to my knowledge a unique and identifying feature in MS/Depocam, replicated in HSMWorks) is for the computer to notice where they occur and clean them out specially. This is an act of retrofitting a correction onto a flawed strategy. I have seen it implemented in the form of little dashes of toolpath that nip in from the side of a contour one tool diameter away from the corner, and by other dashes that go out from the corner along the bisector far enough to clear all the material. It’s ugly because you get sharp 180 degree changes of direction that are not conducive to smooth high speed machining motions.
The primary example of such retrofitting is in WorkNC, as illustrated on their circa 2004 webpage (hosted by archive.org). The WayBackMachine shows a change to the WorkNC webpage in 2005, where these detailed and clear drawings of their strategies disappeared, so I don’t know if it’s still what happens.
The best answer is to use our now-quite-old-and-stable Adaptive Clearing strategy to make a lovely swirling finish to the part. No self-respecting artist would pass this clearing strategy up — if they knew about it — because it’s clean, unique, and looks good.
Unfortunately, I strongly suspect that the art of machining of metal is something that working artists just don’t know anything about. They most likely contract out the menial work to some tool shop with its cranky old expensive software and then pay no attention to the process, because if they did they would quickly notice how trivial it was, with an enormous potential for making gorgeous textures and strange mathematical shapes using kinder-garden level programming skills and a few days of experimentation.
I’d like to work with an artist on this one day. I’ve got a lot of ideas they could use. I can’t do it myself because I am not an artist — defined as someone who can sell their art. Anyone can make art; selling is the social certification which is not achievable by me. I mean, I find it difficult enough getting respected for writing software of the kind that very few people in the world appear willing to do.
Also seen on one of the Rolling Horse’s metal panels is this interesting spiral shape:
Analysis of the scouring suggests that it has been done from the outside inwards, which is unusual. The best theory I can find is given on page 4 of the WorkNC Version 18 brochure:
New Spiral Core Roughing Toolpath
We have designed a new roughing toolpath to generate optimised fluid toolpaths on core shaped parts. A feature of this toolpath is the low number of retracts due to a continuous spiral trajectory at each Z level. Machining times are kept to a minimum and tool service life is maximised.
although there is no actual core here. Given the quality of the rest of the machining on this base, its aesthetic appeal is probably accidental.
Still. If the Computer-Aided Manufacture (CAM) industry weren’t so invisible, its software development threads couldn’t have survived in such a stagnated state of mismanagement by the entrenched system of corporations, giving me a chance to beat it with code written in a spare room in Liverpool.
We’ll see how the benchmarks perform when I finally get through with this round of constant scalloping stepover work. Often it gets difficult to keep up the motivation to plug at it day after day. Sometimes it takes a dose of big-headedness to get the will to carry on.