The "original" ruby-tipped spin tops: crafted without compromise
Kickstarter Original : This is the original design from my Kickstarter project. I still think it's the best. For me good design is all about balance and simplicity.
Making a good two-piece top is also exceedingly difficult. I retired the design for over a year and spent hundreds of hours prototyping to maximize consistency and performance. The tolerance level on both the spindle diameter and bore of the ring are necessarily held to +/- 0.0001 inches...basically the minimum tolerance the lathe is capable of.
Holding this tolerance requires inspecting every 5 parts to make sure the machine is on size. Over the course of the day, the machine will drift up to .002 inches as air, machine and coolant temperature changes. You'll note this is 20x the allowable deviation. Making parts this precise comes at a cost. If you'd like to geek out you can refer to this article on "The High Cost of Tight Tolerances" on the CNC Cookbook blog.
Even with all this effort, the simple act of mating two separate parts together always introduces some amount of error and imperfection. What most makers won't tell you, is you might get a "perfect" top...but you might not. It's become clear that performance falls within a statistical distribution and making every top absolutely perfect simply isn't a realistic expectation. That said, the new two piece top should (on average) spin even better than the original, and that's why I'm bringing back. This is as close to perfection as my current skills, knowledge, and equipment allow.
Materials: The C145 TeCu (Tellurium Copper) used in this variant is copper alloyed with .5% Tellurium for hardness and machinability. C145 is a "free machining" material, which means it machines VERY consistently. Materials are rated for machinability on a 100% scale. C145 is approximately 85%. Tougher materials resist cutting which wears the tool faster and leads to less uniformity and "out of tolerance" conditions.
The 6061 aluminum spindle is strong, light weight, and raw machined aluminum. I normally nickel plate all of my aluminum parts, but it's just not necessary here. I also really like the contrast of the "cool-colored" aluminum next to the warm brass.
Contact Point Options: For complete information, please see the "contact points" tab on this page. Of course the ruby is the ultimate in performance and awesome...can't beat that combination. It's a little bit fragile if you compare it to a Mac truck, but a little bit of knowledge and care will keep it spinning for a lifetime. I mean, it's nearly as hard as diamond and those are "forever."
>>> Broken contact balls are not covered under warranty. NEVER drop the Lambda top onto a tile or granite surface or the ball may shatter. Contact points can be replaced in tops that have hollow spindles (all current models)...assuming there isn't other significant damage to the top. <<<
To be honest, I'm just as surprised as you are. My friend Joe, from Scout Leather Co., has been telling me for months that I should make a top. My response was always, "I make tools, not toys." But I was intrigued. Who doesn't like tops, right? Please check out the Kicstarter video just below :)
One afternoon I had a few hours to play around on the lathe. I had no plan, I was just cutting a top free-hand on the lathe. No measurements, no design drawings. Instead of cutting a cone for the tip, I dug around in an old project box and came up with a ruby sphere I bought for another job. The first time I spun the top it was obvious that I created something totally different in performance and physics from anything I had seen before. I showed the prototype to a few people and the most common response was, "Wait, it's still spinning? Are you sure? It doesn't look like it's moving.There is no way it's still spinning." No one else had seen anything like it either. I thought that was pretty awesome, and I believe awesome is worth sharing.
Packaging: Every Lambda comes in a snap-top box that serves double duty as a storage container and a display stand. Please be careful when you "present" this top to someone. You might preface the gesture with, "So I'm NOT asking you to marry me right now. I just want to show you this top." Or if you are actually going to use the Lambda as a token of your everlasting commitment...then you are the most awesome person ever. Send me photos.
If you know my work, you know I don't mess around. The Lambda is not intended to be a record breaker, but rather an expression of how I see the world: the ideal balance of performance, physics, and aesthetics. However, you are going to have a really hard time finding something is the same size/weight class that will outspin this top.
Enough chit chat; I present the Prometheus Lambda top.
Yes this is a video...it's not a still image! If you stared at it for a few seconds and then said "woaaah," we are on the same page. Welcome to my project :)
The secret ingredient (beyond a solid design based on Newton and "the physics") is the instrument-grade ruby sphere. You heard me right, I said ruby. This type of manufactured ruby is used in things like Rolex watches, super-precision measuring instruments, fiber optic transmission lines, and other really expensive and/or sciency stuff. The hardness is 9 on the Mohs scale. Diamond is one of the few harder materials and scores a perfect 10. That alone is awesome!
From the manufacturer: "This material has five times more abrasion resistance than carbide, zero porosity, high temperature tolerance, extreme chemical resistance, and extreme hardness." I know, I know. How tough is it? THIS tough.
The video shows a ruby smashed between the steel top of my bench-vise and a 16oz. steel-faced dead blow hammer. Yes, I hit it really hard. Yes, it did break. It's tough...not indestructible. Just treat it like a ruby and you should be fine. If you treat it irresponsibly...it will break, as demonstrated above :)
As before, avoid spinning on (or near) tile and granite surfaces, both of which have a higher surface hardness than steel. A significant impact (on something that hard) can shatter the ruby.
What's up with the hole in the spindle? That is 100% physics right there. Brass is more dense than aluminum; and making a top out of solid brass moved the CG (Center of Gravity) slightly higher when compared to the aluminum top. If the CG is too high the top will not want to stabilize. I tried a number of strategies to lower the CG on the top.
Nothing was working very well and I had the idea to drill out the core of the top "just to see what would happen." Like the discovery of Champagne, it was a happy accident. I'm a scientist at heart, and that is one perfect, beautiful 0.160 x 1.25" hole because it's EXACTLY what was needed to drop the CG right into the sweet spot for a perfect spinner. I bet you start to see this one on "other" tops out there in top land. It didn't take long for people to catch on to the ruby thing right? I don't mind that (much) but there's still some value in life for being the "original." At least that's what I tell myself.
Through the looking glass: Is awesome a feature? Yeah, awesome is a feature. One additional feature of the Lambda Solid is you can look right through the ruby. This shot is taken looking down the hole in the stem of the top, not looking at the bottom. I've gotten a lot more enjoyment out of watching the ruby sparkle when you hold it up to a light; and I think that's one major thing that was missing from the original two-piece Lambda.
Another added benefit of the hollow spindle is that any contact point can be replaced...assuming there isn't other significant damage to the top.
Sphericity: The "sphericity" of the Lambda's Grade 25 ruby is 25 millionths of an inch. Take an inch. Divide it into one million (1,000,000) slices. The amount of error is less than 25 slices...out of a million. The majority of machined parts are manufactured to within about 0.001 inches. I created the chart below to make blowing your mind easier on your brain.
Yes, I know that's not "perfectly" round, but it makes for good reading right?
Surface Smoothness: Below is an electron micro-graph that will give you a reasonable comparison between a metal "machined" surface and the surface of an instrument ruby. The image on the left is the ground edge of a razor blade. This is probably a much smoother finish that you will see with machining. However, compared to the surface of a ruby sphere at the same scale, it looks like the Grand Canyon.
Let's agree to call it a cone. A cone isn't a very good shape for the contact point because you are always on one side of the point...or the other. This means the top will have a hard time balancing upright, wasting energy during the early spin, and then falling over early during the late spin when the top is losing RPM. It's inherently imprecise.
The perfect sphere means there is always a perfect point of contact with the surface, wasting less energy and spinning longer. It also means the Lambda is better able to spin along its axis; therefore, it does not exhibit the large amount of precession (angular wobble) that you see in a traditional top (above).
The Lambda name is derived from the Greek letter "L" which is the physics symbol for angular momentum; the Newtonian principle that keeps a top from falling over. I'm not a physicist, but Idid stay at a Holiday Inn Express at some point during college. Here we go:
ANGULAR MOMENTUM (L) = RADIUS (MASS x VELOCITY)
This equation is all you need to know about tops. For a given top, the size (radius) and weight (mass) are fixed, so your only variable is velocity. If you want more spin, you need more speed. How fast can you spin it? The (major) factors that reduce spin time are friction and the geometry between the top's "contact point" and the target surface. You get to pick the surface, but I get to pick the contact point :)
POLAR MOMENT OF INERTIA (Ip) = p(r)r^2dV
Don't sweat the details. That just means a unique feature of the Lambda is the use of 2 different materials in the design. It looks awesome and it increases performance. 6061 aluminum is used for the spindle to decrease the polar moment of inertia...in other words, reducing the amount of force it takes to get the top up to a given velocity. If you remember, the more velocity the more angular momentum...and a longer spin time. Solid brass is heavy, really heavy. It also machines beautifully. If you recall, mass is another important component to angular momentum, making brass an ideal material for the outer ring.
It depends...on a lot of different factors. How long "will" it spin is entirely up to you. How long "can" it spin is entirely unknown. My personal record (unofficial) is over 12 minutes. Check out the video below for a "bar-setting" unedited 10 minute spin.
Can you beat me? It's gotta be on video! Submit your "video response" to my 10 min spin on the YouTube page (link) !Your spin-time can (and will) vary. However, I'll leave you with the guesstimates below. These are based on my personal experience, and observation of other people testing the Lambda. If you can't seem to hit the numbers below, give it a little more "wax on, wax off!" That means "practice" in case The Karate Kid was after your time. Not the new one, the old one :)
Just keep in mind that trying for a long spin is one way to enjoy your Lambda, but it's not the only way!
I tested a lot of different surfaces in search of the best one. I tried marble slabs, granite surface plates, glass dinner plates, ceramic bowls, various mirrors, optical lenses, and chemistry lab glass. The Lambda may spin for so long that you won't have a flat enough surface unless you work in a laboratory or machine shop. After a couple minutes it will "drift" and eventually fall off the edge.
The best thing to use is any kind of concave dish. However, I had a hard time finding anything in my kitchen where the center of the plate/bowl was actually the lowest part. Most had a raised or uneven area in the middle and this throws off the top. Right now my favorite surface is a little 5" shaving mirror (12x magnification) that you canbuy from Amazon. It's a reasonable size, is fairly durable (for a mirror) and has a flat back so you can set it on a table. The smooth curve of the mirror means you don't need a perfectly flat surface, the top will naturally find the lowest point.
Please keep the weight and diameter in mind when comparing tops. These details can be found on the "specifications" tab. Ignoring other factors, increasing the mass and/or diameter will increase the potential spin time. That's just physics. A big top will spin longer than a small one. A heavier top will spin longer than a light one. Materials: Brass ring, aluminum spindle, ruby tip Some of the photos show a black ring. This was an early prototype and not offered as an option.
My prototype tops are manually machined on my Hardinge HLV-H toolroom lathe. Check out the video below for a quick montage of making the very first Lambda top.
The Lambda top is made in-house on the Haas CNC lathe I purchased with the funds from my first KS campaign. All of the raw materials, including the instrument-rubies, are domestically manufactured.
Ruby and stainless tops are carried in inventory. Al2 O3 and SiC tops are assembled to order and will delay shipment by 1-2 days. Now you can choose between instrument ruby, stainless steel, Aluminum Oxide (white), or Silicon Carbide (dark gray). Aluminum Oxide and Silicon Carbide are considered "ceramic" ball bearings.
You will not notice a difference in performance between the contact points, but some people enjoy the difference in appearance, and science behind the materials.
Instrument Ruby is a crystalline form of Aluminum Oxide and called Corundum. Corundum is a naturally occurring mineral, but instrument rubies are synthetic. This material has the distinction of being the very first gem mineral artificially created in a laboratory. A small amount of impurity (Chromium) gives ruby the distinct red color.
Stainless Steel Bearings a good choice if you never want to worry about breaking the contact point. The steel balls used in the Lambda tops are 440C Passivated Stainless Steel. This material is hardened and highly corrosion resistant. 440C is the most common material used in high-quality bearings. It's superior to chrome steel, but not the most exotic steel bearing material.
Aluminum Oxide (Al2O3) balls are classified as a "ceramic" because they are sintered from a powder base. Chemically, this is the exact same material as ruby or sapphire, but it is not a crystalline structure. Al2O3 is most commonly used as an abrasive in the manufacture of sand paper. It is also the coating that grows on aluminum when it is anodized. These ceramic balls are typically used in bearings that see extreme temperatures.
Silicon Carbide (SiC) balls are also "ceramic" and used in even more extreme bearing applications. SiC is heat tolerant up to a staggering 1800*C. It's commonly used in the manufacture of ceramic brake discs, ballistic plates in bullet proof vests, and LEDs. I recommend SiC for the extremely heavy tungsten top because it is the most durable of the three exotic contact point materials.
Durability: Contact points cannot be repaired or replaced. They are permanently press-fit into the spindle to achieve the desired degree of balance and accuracy.
The stainless bearing is the most durable option across the board. Clumsy? Steel. Got kids? Steel. Will you cry if the contact point breaks? Steel.
So why all the fuss about exotic contact points? The difference is the ruby and ceramics are MUCH harder than steel, and will spin more efficiently. It's like the difference between ice skating and snow skiing...both water...both fairly "solid" but which one is more efficient for sliding on?
A ruby is a ruby, and if you abuse it...it can chip. It's like a wine glass; works fine until you drop it. The ceramics can also shatter if subjected to enough force, but are generally tougher than the ruby. Silicon Carbide is the most durable exotic material.
|Material||C145 Tellurium Copper & 6061 Aluminum|
|Where it's Made|