Friday, April 6, 2018

Main plate holder [watchmaking]


The purpose of this quick report is just that - to provide an update to those who follow our watchmaking progress. Also, we feel that sharing our trials and tribulations may one day help someone on their own watchmaking journey.
Last week we started to prototype the main plate. The main focus was on positional tolerances and working out the 'perfect' press fit for the main train jewels. But it wasn't long until we figured out that we are wasting too much material; precisely over 60%. In addition, our work holding method was excellent in relation to rigidity, however, our solution would be very inefficient for mass production - even a quantity of just a dozen pieces at a time.
We had two options: To continue with prototyping or to pause and find a better clamping solution before we go any further. I voted for the first option: to keep learning and not to worry about waste. However, I was quickly outvoted by Josh (who already had Andrew on his side). The final straw was a video which clearly shows a very effective mainplate holding solution on Willemin Macodel CNC, as demonstrated at Baselworld in 2015.  Here is the link to it.  Definitely worth watching:
In just 3 working days, putting in a solid 50 hours of work, Josh and Andrew designed, coded and manufactured our new 'clamp'. The benefits are already paying off: 
- we can use a smaller blank than before, while there is no compromise on rigidity;
- the brass waste is now below 50%
- the new work-holding piece allows for both sides milling plus 90 deg side cut without having to re-clamp the piece;
- and, most importantly, the new blanks could be clamped directly without pre-machining preparation which saves 25 minutes per piece!



Thursday, March 29, 2018

4-Jaw Chuck

Some hobbyist machinists love it - and others hate it. And, I guess, it is fair to say that those who hate it have actually never got around to learning how to centre it properly. Which is rather a shame because there are countless YouTube videos out there dealing with the subject. 
Our Schaublin 102 is still somewhere south of Suez, but the 4-jaw chuck arrived separately this week. It was a 'non-catalogue' accessory supplied by Rohm. This was a bit of surprise - after all, Schaublin is a work-holding specialist themselves. However, the 4-jaw chucks are a much different beast than collets.  
Rohm is a German family business which specialises in chucks. They've been making lathe chucks since 1909 and they are regarded as the world's leading chuck manufacturer. And that's all they do. (Have you noticed that the O in Rohm is actually a chuck?). This German company is very proud of the fact that they can manufacture work-holding pieces up to 4 metres in diameter and weighing 25 tons! When it comes to production capacity: Rohm can assemble 92,000 chucks in 5 days. 
There is something mighty powerful about German manufacturing - and we are proud to have a piece of it in our Sydney workshop.

Tuesday, March 27, 2018

Baby steps



The inner bearing surface of the watch jewel is one of the most 'perfect' surfaces on Earth! Made of synthetic ruby, jewels are laser-drilled, then polished with tungsten wire and diamond paste. Both the inner and outer diameter are perfect as well. This one is R=0.500 mm and the inner radius is just 50 microns. However, the modern jewels are still the pale shade of jewels used in the finest 1800's marine chronometers which were made of real diamonds, hand-drilled and hand-polished - and still perfectly functional today!

Last week we started machining our first watch main plate. The challenge: to figure out both jewel hole sizes and the distances/angles between the jewels in the main train. These are watchmaking machining fundamentals - and yet another of the many best kept secrets in the watchmaking industry. While you can tell your mill where to create a hole, and while you know what the outside diameter of the jewel is, finding the 'perfect' friction fit between ruby and brass is something you can only figure out after a number of attempts. No machine or software can tell you how 'just right' feels like; it is the years behind the watchmaker's bench which ultimately determines the outcome.

The bottom line is this:  If your shaft is the size of a hair, how much off centre can you afford to be?

After last week's exercise, Josh started making a bold prediction how soon we could potentially have our in-house movement. I am still very cautious and conservative, and reluctant to be drawn into speculation, but there isn't the slightest doubt in my mind that one day we will have a true made in Australia calibre. Exciting days ahead!


Friday, March 23, 2018

What others call fine-gloss finish we call roughing



Yesterday we undertook a practical exercise; the roughing of a piece of 316L steel.  Roughing simply means removing the top layer of material rapidly in order to prepare a surface for machining.  In other words, think of it as levelling your block before starting the build of a house.  

The tool of choice was a 4mm end mill.  The machining was done in the Kern Pyramid Nano and it was Andrew and Josh's first job in the workshop.

After the milling operation the surface finish was so smooth and even that it left them speechless.  Actually it's so good that the process can be applied straight away to watch bridges and finish.  
We can only imagine what kind of surface we will achieve with a diamond or ceramic tool.  

Certainly the credit goes to the hydro-static guides of the Pyramid Nano.






Wednesday, March 21, 2018

Well done Maxx Tooling


We are impressed! On Friday we placed an order for a pneumatic-held vice
and it arrived on Monday. That would be an impressive delivery time even for Sydney metro - let alone for a part which flew in from Michigan US.

MAXX specialises in custom engineered and machined parts and tool holders.
If you visit their website you won’t find much about the company (it’s almost an underground operation!). However, they are very serious about quality and precision.

So what is the benefit of a MAXX solution? We can now machine a part in our 5 axes Kern mill and then transfer the same part holder to our Makino EDM to continue with further operations. One part, one holder, two completely different machines and machining processes - no loss in accuracy.

And yes, the EDM clamp held in the MAXX vice was made in Brookvale, in our
workshop. Good job apprentices!






Monday, March 19, 2018

Heat treatment of watchmaking micro-components




Regardless what kind of metal machining shop you intend to setup and what is your intended product (a car engine or a watch!) your ultimate goal is to enable yourself to do certain tasks and processes. Starting with relatively simple ones: To draw and measure. The ability to hold and grab firmly and accurately is the next goal. Then to cut, drill and tap, weld and solder. From then on, you are moving into more serious operations which require sophisticated machinery: turning, milling, grinding.  Obviously your product has to look appealing so you should invest in deburring and polishing equipment as well. Another sometimes overlooked aspect of metalworking: The ability to soften or harden metal. And this is precisely where we are right now.

A number of  steel watch parts (stem, levers, screws, arbours) undergo both pre-machining and post-machining heat treatments. A typical furnace has to provide not only a relatively high temperature (up to 1100 C) but the temperature has to be constant within a very tight range over a very vast spectrum from 100 C to 1100 C. In addition, the parts compartment must remain oxygen-free during the entire process. A quality furnace would also incorporate an oil quenching tank and shielding with inert gas. Yes, while the basics of metal heat treatment are rather simple and well-known, watchmaking furnaces are fairly complex performance-wise.

Taking into account our low volume and part size we have opted for the smallest furnace by Borel. (Don't be fooled with its size - it weighs almost 200kg!) Borel is a Swiss manufacturer which supplies equipment to all the top Swiss watch brands. The company was founded in 1918 by Dr. Charles Borel. As of last year, Borel is a division of SOLO Group, located in Porrentruy, Jura.

If you are a watchmaker or machinist specialised in micro components which require heat treatment then we would be happy to assist - especially if you have issues with scaling and oxidation.  Contact us at workshop@clockmaker.com.au





Friday, March 16, 2018

An addiction to tools is no different to any other - you just need one more

Last year we put out a questionnaire trying to figure out why you follow us?  The majority of our subscribers are here for the obvious:  A love of watches. However, there is a growing group of subscribers who are fascinated with machining, precision and fine tools. And for them, from time to time,  we include a photo or two to illustrate our journey into the world of 'making'. Disclaimer: since I am not the one who operates the machines, I don't take credit for anything you'll see here – all the credit goes to the kids.
Yesterday’s challenge:  To make a tool 'fixture'. Fixtures are work-holding devices designed to hold, locate and support raw material or parts during manufacturing operations. There is another special property of the fixture: it provides a means to reference and alignment for the cutting tool.

In other words:  The quality of your part is directly related to the quality of your fixture. Or, as machinists say: if you want to make a precision part, you need a super precision fixture.  Which logically brings us to a challenge:  If your part is a fixture, then how do you make a fixture to hold  your first fixture?

To cut a long story short, two pieces of steel were individually  and separately cut, then a number of holes were drilled and taped. Locating and guiding pins were inserted. Then the moment of truth: The pieces were joined together. "Where is the gap?" asked Josh. No-one replied; it was well past 10pm and he was in the workshop by himself.  "I am going to engrave Andrew and Josh on this one" was the first thing he told me after arriving home close to midnight.  "In that order?" I’ve asked.
But he didn't hear me. His thoughts were 17,000 kilometres away. "You know, we need to call MAXX in Michigan. They make a super precision vice, and we need one for Kern." "Didn't we just order one from Lang?” I asked.  "Yes, but we need one more!"

And that summed it up. Addiction to tools is no different to any other:  you just need - one more.




Thursday, March 15, 2018

We told him he couldn't leave until he cut the perfect cube


A couple of days ago we locked Andrew up in the workshop. We told him he couldn’t leave until he cut the perfect cube. Material: stainless steel 316L grade, the same stuff the Swiss watch cases are made of.  Luckily, Andrew didn’t bother asking us to clarify what perfection meant to us. To ask a watchmaker’s apprentice to cut the perfect cube on a Makino U32J is like giving the keys of your brand new Ferrari to a teenager and asking him to find out how fast it can go.

Oh, yes, the first few attempts were rather disappointing but he just kept pushing that pedal harder. On the second day he finally got his parameters right ("I was so excited I almost hugged Josh!") . 

So what is perfection? The short answer is:  We really don’t know. Once again, we have reached sub-micron levels where actual dimensions of a metal cube are no longer stable; where metal expands and shrinks purely due to the change in room temperature; where the measuring machine itself influences the piece measured; and where human error in acquisition of parameters is greater than the machine’s ability to measure the part.

Once again on a 10mm-side cube, to his shock and horror, Andrew has reached sub-micron precision. In Brookvale! 






So what’s next? We are now ready to go to the next level: integration of CAD and CAM software so we can finally start prototyping the most intriguing, irregular shapes. Like, for example, levers and springs pictured below. By the way, these springs come from a junk box of American pocket watches from around 1890-1920.  They do look scary - like an arsenal of inquisition/torturing tools! For us, they are highly motivational - if Americans could make such delicate high precision watch parts back then using 19th century machinery, surely we should be able to at least do the same today.


Tuesday, March 6, 2018

Who do you respect?


***Three reasons why you should invest in an Australian watch TODAY

1. We Respect You
We respect your expectations. There is nothing more annoying and useless than a broken watch! When you invest in a watch designed and assembled in Australia, you are investing in a robust, reliable and repairable watch. Rebelde is not 'just as good as any other Swiss-made watch'. It is a timepiece designed and hand-assembled by a third generation Master watchmaker. There is no such thing as a broken rebelde: every single one of the 600 watches assembled in the past 4 years is keeping time and performing as promised.
2. We Respect You
We know you don't see a watch merely as a sum of finely-machined micro components.  Your watch is an expression of who you are and what you stand for.  And if there ever were a brand with a story to be told - a watch you can wear with pride - then it is your Australian rebelde. We don’t have customers - we only have comrades and ambassadors.
3. We Respect You
Wearing a mechanical watch is an act of rebellion and sophistication! In a fast-paced world where lives are governed by heartless and soulless gadgets, mass-produced by robots, your decision to remain stubbornly old-fashioned and to govern your life by a slow-ticking, mechanical watch means just one thing: RESPECT! Your investment in an Australian watch is a smart investment in the future of Australia. Thanks to project 'rebelde' we now have 3 watchmaker apprentices and one student of mechanical engineering who are committed to spend the rest of their lives designing and making watches in Australia. And if we can add just one more supporter every week, then by this time next year we could invite one more Australian apprentice to join our team. We grow when you respect us back.
To place your order select from one of three stainless steel models listed at https://nicholashacko.com.au/watches
$500 deposit. Delivery time: 3 weeks.

Friday, March 2, 2018

Just another painful blister



After 10 days of assembly the Kern Pyramid Nano was finally alive! On Wednesday night all systems were as per specs, fluids were running cheerfully, and the spindle and 5 axis motion left us speechless.  It was the time for final laser calibration; the moment of truth. With the coolness of a pilot of a fighter jet, Michael 'the German dude' set his Renishaw apparatus and commenced the four hour adjustments procedure.  

Now if you are not an engineer then the next sentence and picture below will make absolutely no sense to you, and that is perfectly fine - so no hard feelings.  The total error over the 400mm table was well under 1 micron and not more than 0.1 micron per 100mm of table travel. "So the machine is well within what could be described as a miracle of mechanical engineering?" we've asked. "Actually I am not sure" said cool Michael. "What we see is not the 'machine error' itself but the error in nano-range is most likely just the effects of environmental temperature and vibration of the building."  And finally, it all sunk in. This is precisely why Kern calls Nano - nano.  Too tired to celebrate, we quietly went home, each of us dreaming our own nano dreams... 



Around lunch time on Thursday, I got a phone call from Josh: "Bad news, dad.  The x-axis has just disappeared of the screen. It looks like we have a problem with the linear decoder.  We are now disassembling the entire block, Michael has cancelled his return flight and is extending his stay for at least another week. Yes, we need a new encoder, new cabling and Kern is sending a spare CPU unit from Germany, just in case we need it too."  The four hour sub micron calibration vanished with the X-axis without a single part being machined.
The other day, Elon Musk's Space-X launched Zuma, the top secret US spy satellite. But moments after the launch, like our x-axis, the multi-million dollar satellite disappeared - literally vanished off the radar. Yes, engineering on any scale can be heartbreaking and engineering is not for the fainthearted. 
In January 2012, Pat Farmer accomplished one of the greatest feats in human history. He arrived at the South Pole after the longest and arguably most dangerous run ever. Pat ran for 21,000 kilometres - never complaining about being tired nor disappointed, or his painfully bloody blisters, cramps and injuries. He just ran - and that determination - that physical and mental triumph - put him in the company of the world's greatest adventurers and achievers.
And this is precisely what our "Made in Australia" project is all about:  endurance, not giving up, being tough as nails, and being prepared to pay the price.  And we'll enjoy every bit of that journey, even when it hurts.





Thursday, March 1, 2018

Workshop training exercises well past midnight

When asked by aspiring engineers and entrepreneurs for a 'fast track tip' Elon Musk said: instead of 40 hours per week, do 80 hours. All things being equal you will achieve your yearly goal by June. To get there even sooner, do 100 hours. 
It’s funny how time flies when you learn new stuff. Last night we stayed in the workshop well past midnight. The first training exercise: a 5 x 5 mm block with 1 mm gap.  We got within 2 microns on the first go. The second exercise: toothed cylinder, 8 mm in diameter, watch gear profile. Then another cut: its reverse 'image'. Material 316L.
Made in Australia? You bet.

What we have learned:

If you can imagine it, you can draw it. If you can draw it, you can make it.



Tuesday, February 27, 2018

From the world's smallest watch brand: Makino up and running!

Yes, we are happy.  The 50 micron wire cutter has been successfully installed.   Exclusively for our rebelde comrades: here is the picture of a first test cut. For comparison, the top surface is a standard milling finish , the cube itself is cut by EDM. The finish  can be best described like one on the edge of a razor blade. Scary!
The cutting time for this tiny cube: two hours.  Machining cost:   Just over $120. It goes without saying that only the space, medical and watch industries can afford such costs.  Exciting times ahead!





Another week @ rebelde workshop

This week Michael (the German technician who came to install our Kern mill), Josh and Andrew went through hell. After four 12-hour-shift days, the installation hit a wall with great force: the laser adjustment tool required for 'final alignment' is still on its way to Sydney. Obviously, this delay will cost us time and money but we are still conservatively optimistic that by the end of next week Kern will be up and running. The preliminary test runs are all good: the hydraulics, cooling system and electrical/electronic commands and the main spindle 3-hour tests are all OK.
The complexity of the system is mind-blowing and we have learnt that no part of the machinery can be regarded as 'auxiliary'.  Each component and each parameter is absolutely critical.  For example: the oil in the hydraulic system which is responsible for the movement of the main table has to be chilled to an exact temperature of 21.0 C. For that to happen, the Kern is fitted with not one but two “refrigerators”: one which produces a cooling liquid chilled at 11.3C and the other which 'outputs' 17C.  The final temperature is then finely tuned within the 3-tonne iron cast base which itself acts as a large capacitor. 
Such a fine tuning can be only achieved when one cooler is located as close to the machine as possible, while the other is located as far away as you can place it. The Australian summer is not helping either, with temperatures soaring to 40C inside the factory unit.  The amount of heat generated is close to unbearable and in addition, we are drawing so much current. Right now, the entire system is pushed to the absolute limit which means just one thing:  Further reconfiguration, more insulation, better pipelines and a further upgrade to the electrical wiring.
One thing that needs to be recognised, and given credit for, is that these guys below are just Aussie kids setting up one of the world's most precise machines.  These are the future makers of your watch so don't forget these faces.



Thursday, February 8, 2018

Josh Reporting: One crazy hashtag


"Just finished 8 days of training in Germany, at the precision machine tool builder, Kern Microtechnik!  The red machine behind me in the photo below is the most accurate machine tool in the world, holding a scattered position tolerance of 0.3 microns, which is a 3000th of a human hair! In fact, the research and development team at Kern have actually drilled HOLES through human hair with Pyramide Nano - the very same mill to be used in Brookvale #makinginternalcomponentsforthefirstandonlyAustralianmadewatch. Next stop Switzerland!"