What do you mean by “Precision Machined”?
The majority of time and effort in developing the Kewb was dedicated to the underlying engineering and repeatable production of the mechanism, the puzzles and aesthetics were pretty straight forward by comparison. The Kewbs needed to move and feel as good as they looked. As you make moves with a puzzle cube you are transitioning one bearing surface onto another while constraining the rotation of a moving face precisely; any slight variation of surface position is fed back as a “snag” or “catch” to the user. The denser the material used, the stronger the springs required to hold the puzzle together… the stronger these springs are, the more amplified the “catch” feels.
No part can be made to precisely match design dimensions but we can account for this by specifying a “Tolerance”. We are basically saying the manufactured part will still work if its within the a small range of dimensions. After countless revisions we found that a tolerance range of about 0.002” was the upper limit of what felt right for the main block elements and about 0.0005” for the cylindrical bearing components. Now putting that into context… the average human hair is 0.004 to 0.006” and the average white blood cell is 0.0007”!
This kind of precision is unlike nearly any other metal puzzles, they need looser fits to allow them to be dismantled or moved easily. This kind of accuracy can not be achieved economically though powdered metal sintering, die casting, 3D metal printing or any other addative manufacturing technique. These parts can only be made by traditional subtractive machining methods. Although tolerances like these are held regularly in modern CNC machine shops, they are still considered “tight” and are priced accordingly. It is a time consuming challenge to hit these using the current equipment in our studio, to say the least. There is good reason no one has offered a precision metal puzzle cube for sale in the last 40-50 years!
Are Kewbs the first metal puzzle cubes?
We believe we the are the first to develop the design of a fully functional precision machined metal cube and optimize it for production. The first to make them available to collectors and enthusiasts around the world. And of course the first to layer some of the world's most challenging 3x3 puzzles onto them.
However, we were not the first to make a precision machined cube from bar stock material. We have huge admiration for the likes of Lu Laboritories and Penelope Jamieson, they made beautiful pieces using only manual machining techniques! Honestly, their plans online gave us valuable insights and a great starting point.
Additionally, several limited edition puzzles from major manufacturers have real metal outer shells on them. There are also some fully functional die cast cubes on the market as well. There were some artistic pieces made years ago that had 3 locked layers that could rotate. And of course there are some... lets just say... questionable items floating around eBay.
Does "Made in America" mean what I expect it to?
Absolutely! Phil, like many naturalized citizens, is fiercely loyal and proud to be an American; he wasn't born into it, he chose to be part of it. After being raised in a family that constantly moved around the world with his father's career and being an enthusiastic traveler in early adult life; he has seen much of the world. Life simply doesn't get any better than living here in the Blue Ridge Mountains.
We have a simple rubric, can we get it locally? Is there an American company that makes it to our standards? If so, thats what we are using, period. Walnut, grown and seasoned locally. Leather from one of a rapidly dwindling list of American Tanneries. We need to source some Wave Springs, thats easy, the inventors are based out of Lake Zurich, IL.
We can confidently say Kewbs are 100% American sourced & made. Almost all of our sourced items are also made in America as well but there's a couple of pieces that we are still struggling with. Anyone know an American based manufacture of Aniline Cord? With any luck we will also be able to find a 6-32 Flat Head SHCS thats still made here to hold the stand together.
How long does it take to make a Kewb?
Since the journey began, we have made continuous improvements to our processes and optimized the production steps as best we can. Currently the time from bench of material to finished Kewb is about 26 hours. A good part of that is "machine time" or the time it takes to produce the component parts, followed by the hand work of multiple finishing steps, stand production, leather working, inspection and final assembly. The quick part, at about 2 hours, is the engraving.
Why did you choose Brass to make the Kewb with?
Choosing brass wasn't particularly difficult.
First we eliminated all metals that could corrode or rust. This left us with alloys of stainless steel, titanium, aluminum and the "Red Metals".
At its core, a puzzle cube is just a combination of segmented thrust & radial bearings. As such we eliminated any alloy that would easily gall or cold weld. Now we were down to a few brass alloys. Brass machines beautifully, is dimensionally stable, and lasts for decades. This is the same reason brass was the material of choice for scientific and engineering instruments during the Industrial Revolution. The tiny amount of lead in brass also acts as both a long term lubricant and a self-healing element, ensuring smooth operation for generations to come.
Why is there a hole in my Kewb?
In short, for accessing a precision shoulder bolt during initial assembly and servicing if ever needed. Twisty puzzles are a series of interwoven, segmented bearings. In order to hold all these components together and allow for free moment, the center square on every face pulls inwards towards the core of the cube, using springs. Usually the last few pieces of a regular cube can be snapped into position by extending all of the springs and creating just enough space. A Kewb generates approximately 50 lbs of pull force holding itself together; the standard method of assembly was never going to work.
How should I take care of my Kewb?
We strongly advise against polishing your Kewb. Ever. Polishes usually contain small abrasive particles which will destroy the precision bearing surfaces of your Kewb. We cannot service a Kewb that has this type of damage. We do recommend you lubricate your Kewb using a sulphur free, food grade mineral oil. Nearly all white oils used to protect wooden cutting boards are liquid parafin and will work great. How often do you need to lubricate your Kewb? Well it depends on how you are using it... If you are on mission to solve then perhaps every 5-10 hours of manipulation. If its mostly a display piece, then once a decade will be fine. Only 2-3 drops will ever be needed. Afterwards wipe away any oil on the surface of the Kewb; they were designed to patinate and oil will halt this process.
How do you engrave the Kewbs?
We use a technique called "V-Carving". A pointed cutter with a 90 degree included angle is spun at high speed and moved under computer control to simulate the movement of a "graving tool". The tip of the tool is approximately the width of a human hair, providing unmatched detail and surface finish. This is not a quick process, with a tip that small we are only able to cut at about 3 inches a minute. Techniques such as deep laser etching are what's known as 2.5D operations, burning away material layer by layer leaving stair stepping behind. Think the inverse of FDM printing. V-Carving is a true 3D operation which produces seamless depth changes across the cut and this best replicates traditional hand engraving. This traditional craft takes years to learn as a skill and decades to perfect as an art. V-Carving gives the Kewb this traditional aesthetic with modern precision.
How do you make the leather bag?
For the bag, we chose the highest quanilty full grain pull-up leather. Pull-up leather is a centuries old technique, perfected in America that stuffs the leather with oils and waxes. They are constructed on two industrial walking foot machines that date to the early 80’s; the same vintage as the Rubik's Cube, and the bag maker. A flat bed machine sews the vertical seams and the top edge is finished on a cylinder arm. The design of these machines have remained unchanged for over 70 years. They are stitched with heavy duty nylon thread. The edges are skived for smooth seams. The rivets are set with a mechanical kick press. In short the bag is made by hand, by us, with techniques that have remained unchanged for nearly a century.
How was the line art for Ernő created?
The artwork on Ernő presented a unique challenge. The original patent drawings were created by a professional architect and draftsman entirely by hand. Tory also has a background in traditional drafting, and we wanted to preserve the character of those original drawings as faithfully as possible.
That turned out to be more difficult than expected. Every letter and every number in the patent is subtly different, reflecting the imperfections and personality of hand drafting. V-carve engraving, however, requires precise vector geometry.
We meticulously traced the original drawings on a tablet, then refined every curve and every anchor point by hand. Each character was carefully scaled and adjusted to fit the proportions of a Kewb face while preserving the feel of the original patent.
There isn't a single font anywhere on Ernő. Every line, every curve, and every point was placed intentionally to capture the soul of the original patent drawings.
Why bother with a Kickstarter Campaign?
The founding principle behind the Kewb was to create a puzzle that could legitimately share a shelf with similar objets created by the very best contemporary artists; GarE Maxton, Rainer Popp & Felix Ure to name but a few. As much as I admired and desired their creations, it was a long time before I could afford to own them. It is simply a matter of premium materials and the time & craftsmanship that goes into them. The cost of a Kewb would be well into 4 figures if we continued with the process we are currently using.
Was there a way to move beyond the high cost, boutique production, limited run paradigm that constrains the high end puzzle market, while maintaining the hand crafted details? Could we somehow lower the financial bar of entry into our world of Kewbs?
After carefully considering all our options, the only solution we saw to maintain our standards while being financially viable was to invest in a production grade multi-axis machining center for our own studio. This would free up our existing machine for dedicated engraving, use the new machine to continuously produce components, and allow us to turn our full attention to the hand work. This is exactly the scenario that crowd funding was originally created for.