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Explore Community Submit Build a 15,000 rpm Tesla Turbine using hard drive platters by sbtroy on May 25, 2006 Table of Contents intro: Build a 15,000 rpm Tesla Turbine using hard drive platters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 step 1: Make ventilation holes in the platters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 step 2: Make or reuse spacers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 step 3: Make the shaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 step 4: Make collars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 step 5: Rotor assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 step 6: Make the chamber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 step 7: Make the side panels (stators) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 step 8: Assemble everything . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 step 9: Complete turbine and movie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 File Downloads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Advertisements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Customized Instructable T-shirts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ intro: Build a 15,000 rpm Tesla Turbine using hard drive platters Here's a project that uses some of those dead hard drives you've got lying around. In the Tesla Turbine, air, steam, oil, or any other fluid is injected at the edge of a series of smooth parallel disks. The fluid spirals inwards and is exhausted through ventilation ports near the center of the disks. A regular blade turbine operates by transferring kinetic energy from the moving fluid to the turbine fan blades. In the Tesla Turbine, the kinetic energy transfer to the edges of the thin platters is very small. Instead, it uses the boundary layer effect, i.e. adhesion between the moving fluid and the rigid disk. This is the same effect that causes drag on airplanes. To build a turbine like this, you need some dead hard drives, some stock material (aluminum, acrylic), a milling machine with a rotary table, and a lathe with a 4 jaw chuck. Wikipedia has a good review article (http://en.wikipedia.org/wiki/Tesla_turbine), as well as articles about Nikola Tesla (http://en.wikipedia.org/wiki/Nikola_Tesla), the boundary layer effect (http://en.wikipedia.org/wiki/Boundary_layer), and Reynolds number (http://en.wikipedia.org/wiki/Reynolds_number) (which determines if the fluid flow is laminar or turbulent). I run my turbine on compressed air (40 psi), and it easily reaches speeds of 10-15,000 rpm. While the speed is high, the torque is low, and it can be stopped with your bare hand. I have more details on my webpage (http://staff.washington.edu/sbtroy/turbine/turbine.html). UPDATE (27.MAY.2006): I have a video on my webpage now. It's a 22 MB DivX .avi file. I couldn't get the link to work properly, so go to my webpage above and scroll to the bottom. NOTE: As of 25.October.2006 I lost my student webpage. I have moved everything to http://staff.washington.edu/sbtroy/ Image Notes 1. After spiraling inwards, the fluid passes through these vent holes. 2. The fluid of choice is injected through these ports. By adjusting the relative pressure between them, you control the rate and direction of rotation. I only have one port on my design so it can only spin in one direction. http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ step 1: Make ventilation holes in the platters Step 1 should probably be to disassemble some hard drives but I assume that if you read Make, you've already figured out how to un-Make a hard drive. The easiest way to make vent holes in the hard drive platters is with a milling machine and a rotary table. Center and clamp a stack of several platters to the rotary table and then you can cut any radially symmetric pattern fairly easily. Just be sure that you use aluminium platters because ceramic platters will shatter when you drill into them. I made two sets of platters; one with a radial array of holes, and one with radial arcs. The platter with radial arcs in the picture was on the top of the stack and took the most damage. The platters beneath it have very little tear-out and look much better. Image Notes 1. The platters beneath this top one didn't have this tear-out. step 2: Make or reuse spacers The ideal spacing between the platters depends on several variables including the fluid viscosity, velocity, and temperature. You could go through the calculations (http://en.wikipedia.org/wiki/Navier-Stokes_equations) and make a set of spacers, or be lazy and just reuse the spacers from the disassembled hard drives. I was lazy and reused the spacers that were originally in between the platters. The advantage to this is that they'll have the same inside diameter as the platters. They're about .050" thick where the ideal spacing is closer to .012" but the increased distance doesn't make that big a difference in this case. http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ step 3: Make the shaft This is just a piece of aluminum stock turned on a lathe. The center diameter is about .98" (which is the inside diameter of the platters) and about 1.77" long (so it will fit in a piece of 2" thick acrylic). The thinner sections on each end are turned to fit the ball bearings I pulled from a box of scrap. step 4: Make collars The collars are made from more aluminum stock are wider versions of the platter spacers. The inside diameter is also .98" but they're about .3" thick to hold a #10-32 set screw. http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ step 5: Rotor assembly Center the platters, spacers, and collars on the shaft and tighten the set screws to hold everything together. I used 11 platters, and 10 spacers. Try to line up all of the ventilation ports. If there isn't enough tension between the two collars, the platters can rotate around the shaft instead of with it. step 6: Make the chamber This is a 4.75" x 4.75" x 2" piece of acrylic that was bored out on a lathe using a 4 jaw chuck. The intake hole is taped for a 1/4" pipe fitting and all of the other holes are 1/4 - 20. I used acrylic because it's what I had around and because it's going to be used for lecture demonstrations. You can use metal or even wood. However, if you plan to use steam instead of compressed air, wood might expand too much. http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ Image Notes 1. Air flows in through this port causing the rotor to spin clockwise. step 7: Make the side panels (stators) The side panels are 4.75" x 4.75" x 0.47" acrylic with untaped .25" holes to screw to the main chamber. The center hole is 0.6" and the counterbore is 0.28" deep. The two 0.6" holes (one on each side) are the ONLY exhaust ports. The air spirals inwards across the face of the platters, through the ventilation ports, around the air spaces in the bearings (2nd picture), and finally out through these two holes. However, more exhaust holes in the side panels might improve efficiency. http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ step 8: Assemble everything http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ step 9: Complete turbine and movie I couldn't get the link to the movie to work so go to my webpage (http://staff.washington.edu/sbtroy/turbine/turbine.html) and scroll down to the very bottom. Please post (or email me) any questions or comments and I'll do my best to answer them. Thanks for reading, Steven http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ Image Notes 1. 1/4 - 20 socket head cap screws with plastic thumb screw knobs. File Downloads Turbine_CAD.dwg (70 KB) [NOTE: When saving, if you see .tmp as the file ext, rename it to 'Turbine_CAD.dwg'] Turbine_CAD.pdf (22 KB) [NOTE: When saving, if you see .tmp as the file ext, rename it to 'Turbine_CAD.pdf'] http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ Related Instructables [blog 2006-0615] Instructables Project Contest - April/May 2006 Results! by instructables-dan The Making of the Prototype Tesla CD Turbine (video) by mrfixits Create A Beautiful Vortex (video) by mrfixits Recycled OffGrid Tesla CD Turbine PowerBoost Blender by mrfixits SinkScience with the Tesla CD Turbine by mrfixits Tesla turbine from old hard drives and minimal tools by gerrit_hoekstra Build an Amazing Tesla CD Turbine by mrfixits Tesla CD Turbine With Scary Steampunk Laser PumpkinCutter Attachment by mrfixits Advertisements Customized Instructable T-shirts Comments view all 161 comments 50 comments Add Comment Steam Head says: Oct 27, 2008. 9:10 PM REPLY How would steam be as a motive power? That would give the turbine some extra "grunt" I would think. Fantastic Instructable. IceCadavers says: Oct 26, 2008. 3:01 PM REPLY I might have missed something here, but I don't think I've seen any suggestion of using this type of turbine in a Stirling engine? That's essentially the concept Iamdenteddisk was referring to, an engine that uses the heating and cooling of fluid (and thereby expansion and contraction of said fluid) as an extremely efficient source of mechanical energy. The difference is that Stirling engines move a piston, not a turbine... anybody more educated in these things know if this could be more or less efficient than a piston? iamdenteddisk says: Sep 8, 2008. 9:57 PM REPLY hi luke luck and all you tesla turbine viewer's I wanted to post an idea I had about the turbine being used in a free energy project I would love to build one but cant afford it or a copyright of my idea but here it goes.. are you familiar with the hand boiler or love meter? ifso we need to try piping one of them in large scale to the turbine A worthy experiment Im sure someone who has a prebuilt turbine can do. I attach a picture of the boiler and P.S the colored liquid is methanol or comercial grade alchohol available as dry gas at the auto parts Im all about free energy and a thermal fuelless engine sound like a winner to me..iamdenteddisk@yahoo Suarve says: Sep 24, 2008. 10:19 AM REPLY iamdenteddisk - I can see where you're going with this - check this out http://www.youtube.com/watch?v=aQmfRNzLNQs I think this is the type of thing you are on about? by using the cooling properties of even just a slow moving body of water you should be able to get the methanol shooting around the tesla turbine... http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ iamdenteddisk says: Sep 8, 2008. 10:19 PM REPLY se both my first and second post, if the methanol boiler eperiment is a success then my next offering would be to connect this dc motor via a sleeve and setscrews and you have a high voltage dc genorator or add the charge controler to have a thermal electricity genorator add some black paint a parabolic mirror and insulate here and there you got a marketable and patentable product for the masses ...P.S im a physics guru and would love to colaborate on this proj if any takers! iamdentededisk@yahoo wjbombo says: Apr 14, 2007. 9:47 PM REPLY Could you combine this with a magnetic alternator as an input to create electricity? wjbombo says: Apr 14, 2007. 9:57 PM REPLY To be more clear, could this tesla turbine spin a platter of permanent magnets (like the windmill project http://www.instructables.com/id/EDTMO3QLQIEP287OGM/ ) and extract the energy (some of which could power the air pump) ? How many watts is that air pump using in this experiment? wjbombo says: Feb 29, 2008. 9:03 PM REPLY Someone please show me where I asked for anything in violation of the law of conservation? I specifically asked what the energy usage was to determine how efficient this electrical generator could be... given the setup I describe. If there is a very limited loss of energy and this is highly efficient, isn't it worth considering looking into to determine if could be a better alternative to coal, oil and other old energy technologies currently in use? So the original question remains unanswered... How many watts is that air pump using in this experiment? Peace. allElectrick says: Sep 5, 2008. 9:01 AM REPLY your 100% right wow-amazing says: Jul 28, 2008. 7:57 PM REPLY Tesla turbines and electric generators are very efficient. If you where to power an optimized turbine driving an optimized generator, you would only lose about 15% of the original input energy. That wouldn't be a bad idea for a power plant. Full Frontal Graphic says: Apr 1, 2008. 2:22 AM REPLY I think they are objecting to: "extract the energy (some of which could power the air pump) " because the air pump is providing the force that turns the turbine, the air pump, no matter how efficient, cannot run on the amount of energy this puts out if the only input power to the turbine comes from the air pump. it would be similar to the perpetual motion machine where falling water turns a wheel that lifts the water... or a generator that charges a battery that runs the generator or using hydrogen power to crack water into hydrogen and oxygen or a clock that uses a pendulum and falling weight to raise the falling weight one notch each time it falls one notch or a photovoltaic panel powering a lamp that shines on the panel and creates electricity to power the lamp or using steam power to to generate electricity and then using the electricity it produces to run the electric heating coil that heats the boiler to produce steam or a city where streets are one way in alternating directions, and the streets are all downhill, so you can coast your bicycle downhill wherever you go or a fan powering a windmill that generates electricity to power the fan ... sorry, I'm not being nasty, just providing a bunch of examples so you can pick one that's the most understandable. all of those "violate" a principle of physics (specifically thermodyanmics) that is called "the Law of Conservation of Energy" . Nobody is accusing http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ you of anything criminal. kscience says: Jun 29, 2008. 2:39 PM REPLY Ah yes, the laws of physics. Elegant, repeatable. Not like the fools errands we live with daily "laws" produced in the congress and senate, or by executive order..... ;>) Full Frontal Graphic says: Apr 1, 2008. 2:25 AM REPLY "or using hydrogen power to crack water into hydrogen and oxygen" ... and using the resulting hydrogen to power the "hydrogen cracker" cholo71796 says: Apr 24, 2008. 7:10 PM REPLY Sir, I think you've misunderstood Wjbombo. The way I viewed his comments states that he is curious as to, if possible, go about harnessing the energy created by the turbine and using it to power some of the turbine. See, here he says "and extract the energy (some of which could power the air pump) ?" darthdavid says: Apr 23, 2008. 4:44 PM REPLY You're thinking of the Second Law of Thermodynamics, which states that over time the total entropy of a closed system can only increase. In basic terms, nothing is perfectly efficient so unless you have external input of energy to a system it will wind down or become more entropic. i make shooting things says: Feb 29, 2008. 6:59 PM REPLY the law of conservation of energy states that energy can not be created or destroyed; when ever there is movement friction with air or other object is created this causes heat which "waist energy " or at least it cant efficiently be returned to the system. This is why perpetual motion is impossible. harleyloaf says: Mar 6, 2008. 11:08 PM REPLY Actually the law of conservation of energy states that energy can not be created or destroyed, it can only be changed from one form to another. e.g. friction turns kinetic energy into thermal energy. James (pseudo-geek) says: May 7, 2007. 1:32 PM REPLY sorry, but that idea doesnt work. you cant get more power out of something than you put in.......... unless its that one guys experement with alternating magnets....I'de have to go get the stuff out of my room to show you and I'm too lazy. holomorph says: May 9, 2007. 6:13 PM REPLY But you could run the turbine off steam rather than an air compressor. James (pseudo-geek) says: May 9, 2007. 6:42 PM REPLY I think you missunderstood his point. I think hes trying to make a prepetual motion machine. The Fallen says: Dec 20, 2007. 11:37 PM REPLY that's kinda impossible, but still cool to see how far people can get on those machines craz meanman says: Feb 29, 2008. 2:50 PM REPLY it is impossible. you can make things like perpetual motion machines but energy is always slipping away and into different forms... James (pseudo-geek) says: Dec 21, 2007. 4:26 PM REPLY agreed Car Dude says: Mar 9, 2008. 2:39 PM REPLY know what I've been thinking... a really good perpetual motion machine is, a hydrogen car, water in, water out. you know, with the electrolysis process and all. the exhaust is steam. so it should work... Dungeonbrownies says: lol, good one http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ Apr 2, 2008. 9:48 PM REPLY Full Frontal Graphic says: Apr 25, 2008. 12:18 AM REPLY yeah yeah it's just water... but think how expensive water would become if we used that idea. ;-) -Aj- says: May 10, 2008. 11:34 PM REPLY only prob is theres a bundle of energy lost in the mean time. youd need to split the water into hho first. which requires energy. if done inside the car then solar or something. in which case whats the point of the hydrogen part at all? powering a car on hydrogen, hho or batteries is only an alternative storage medium as opposed to petroleum. if your using a coal power station to extract hydrogen or to charge the batteries then theres no point because the coal power station is still producing the greenhouse gases the car would. (although they are more efficient then a car, so take that into account) splart says: Aug 26, 2008. 8:27 AM REPLY Great project!!..................Now give us all a list of green recycle sustainabilty applications for this baby using ...say compressed air ...or whatever. This would make it all the worth more while. b-train says: Apr 21, 2008. 9:24 PM REPLY hi i am sorta confused with the idea of tesla turbines, i understand how and y they work but not y you wld want to build ur own mini tesla turbine, wat wld u use it for? is it more of a novelty thing or do u guys power stuff fans n stuff from water hoses? thanks wow-amazing says: Jul 28, 2008. 8:00 PM REPLY It's mainly a novelty, but it would be and interesting project to turn into a high powered fan. MY says: Jun 29, 2008. 11:34 AM REPLY Tesla's bladeless turbine design is an excellent method of converting fluid momentum (water, steam, compressed air) into rotational force which can drive motors, generators, etc. If PROPERLY designed (both rotors and nozzle) it's efficiency rivals far more expensive designs such as the steam turbine . That's the beauty of the Tesla Turbine...the elegance of it's simplicity. For more info you might consider joining the Tesla Engine Builders Assn. bedeboop says: Jul 26, 2008. 3:23 PM REPLY At the risk of offending...could I, at home, use this somehow???? I read about making the Tesla...just not sure why I would make one at home and if it has a practical use for home I would love to know. tater_3001 says: Jul 16, 2008. 11:36 AM REPLY if you were to add a connecting piece to connect the platters like a water wheel except in a spiral fashion down the spindle, would the platters move faster and create more energy? kscience says: May 1, 2008. 7:47 PM REPLY This is a great proof of concept piece; however, in the Tesla Turbine book from Lindsay Publications I had, the one he built was 100 lbs, and 10 hp. The discs were some nickel silver alloy and were quite heavy. This was for a reason; it is important in a motor to have a flywheel, to gain some moment of inertia, a way to store the energy. HD disks are perfect for demos but no energy is stored in them over time, sadly. But you can run em on a desktop or feel their gyroscopes in your hand. The guy holding the original turbine for the photo did not look happy about it... a sort of "exponential horn" in reverse between the circular tubing input to a uniform slot covering all the discs in the stack would certainly up the efficiency as well. MY says: Jun 29, 2008. 11:50 AM REPLY As others have already said, Tesla's claim was 10hp per pound, but to your point about the necessity of a flywheel - Tesla himself arrived at that same conclusion as is evidenced in his last patent application. His submission to the British patent office clearly shows the addition of thicker outermost discs, tapered inward. The central star washer/hub and cross-plate rivets can be disregarded as they were clearly attempts to work around imprecise manufacturing equipment and inadequate raw materials. Tesla was so far ahead of his time that most people are still not aware of his contributions. He totally spanked Thomas Edison on many issues (Tesla often derided Edison's brute force techniques as wasteful and unnecessary). In fact, Tesla was an Edison employee until he couldn't stand the close mindedness any longer. I believe their falling out was over Tesla's idea that AC current was the wave of the future, while Edison and his team remained sold on DC. Look it up for yourself - it's fascinating reading. tdbrady says: Jun 30, 2008. 10:15 AM REPLY The "falling out" was caused when Edison refused to pay the $50,000 bonus he promised for a performance design improvement on one of Edison's designs. Tesla promptly resigned when refused payment. http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ kscience says: Jun 30, 2008. 11:21 AM REPLY Sigh; some things just don't change. George Westinghouse continued the tradition of ripping Tesla off as well, ignoring his ideas that Westinghouse wanted to keep down, as his tooling was already making him rich with his existing machines...... kscience says: Jun 29, 2008. 3:00 PM REPLY And while the ruthless Edison did Animal Experiments to try to discredit Tesla, whose power runs our grids worldwide today? The most efficient one, which happens to be the easiest and cheapest to scale. Viva Tesla...! wow-amazing says: Jun 4, 2008. 6:19 PM REPLY That's strange, nine times out of ten, I've read that Tesla's turbine produced ten hp per pound, but you could be right. Also, the tesla turbine didn't need a flywheel because it was self starting and had significant torque at zero rpm's, so the only real requirement for the disks would be that they're strong. I could be totally wrong, but that's from my experience. kscience says: Jun 4, 2008. 7:54 PM REPLY Umm, if anything in physics allowed us 10hp per lb, or 7500 watts per pound, I imagine we'd be using it. Its amazing what is on the Internet that gets read, spread, and believed. There are books out on Tesla's turbine. They tell a truer history than suggesting 10hp/pound. Solid fuel rockets maybe. Google turbines to see that they are fast, not torquey. The STP indy turbine car needed a huge transmission....! Finally, the Tesla turbine is a flywheel, really, isn't it? A distributed one, but it is a wheel that flies on its bearings. Big enough to store energy, if not made of hard discs. wow-amazing says: Jun 5, 2008. 6:00 PM REPLY You'd think so, huh? Yeah, this is everywhere. Have you ever read a 60 year old book talking about the tesla? And yes, I know turbines aren't torquey, but relatively, the tesla is pretty torquey. BTW, tesla turbines can very easily be over 90% efficient because of the way the energy is transferred to the disks, and gasses moving at the velocity they are out of a jet engine have quite a bit of energy. To answer your last question, no, a tesla turbine isn't just a flywheel that stores energy. The amount of energy you could store in a flywheel is minimal and hardly usable. Also as a side note, you'd use hydrostatic transmission instead of a mechanical one to reduce the speed. bwcbwc says: Jul 26, 2008. 2:12 PM REPLY How would you scale up the model to increase the torque without increasing the weight too much? Presumably an air pressure increase would be required to provide the additional energy, but would you get more torque per mass from larger-diameter disks (anyone have some old 12" laser video disc around?) or by adding multiple channels of airflow and multiple pairs of disks along a shaft? wow-amazing says: Jul 27, 2008. 8:48 PM REPLY Powerful tesla turbines spin so fast that gearing them down to a reasonable speed produces incredible amounts of torque (for their size and weight). kscience says: Jul 27, 2008. 9:47 PM REPLY Its been years since I heard about the magnetic power transmission developed in the northwest; I suspect it was bought up by this companyhttp://www.dextermag.com/MagneGear-RMG.aspx google keeps leading me to this site. Magnetic transfer is more efficient than friction laden gears, though, it seems. So do not neglect trying this newer way of speed reduction/torque magnification.... kscience says: Jul 27, 2008. 9:24 PM REPLY Thank you, wow-amazing. This is so true. There is also magnetic coupling, as is being manufactured in Port Townsend Washington, which is more efficient than gearing. Still, Tesla made his turbines to run on highly viscous fluids, like Steam, not Air! If air is all you have, compressed and frigid, at least input it with a venturi to mix it with ambient temperature air to get some modicum of condensation...! Its still not as good as steam for motive transfer but its better than cold dry air...... wow-amazing says: Jul 28, 2008. 7:51 PM REPLY I think part of the reason why tesla turbines are so genius is because of their versatility of compatible powering fluids. The tesla turbines' design could be optimized for use with all sorts of fluids, which made the turbine very efficient and powerful. BTW, the magnegear is a very good idea, and one that I have had recurring thoughts on as how to incorporate that with a tesla turbine. rainCheck says: ANY spining disk is a flywheel http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ Jun 27, 2008. 4:24 AM REPLY wow-amazing says: Jun 29, 2008. 12:54 PM REPLY But often times can't store enough energy as to be practical, which kscience claimed. kscience says: Jun 29, 2008. 2:33 PM REPLY Sort of like in old vacuum tube amps with old filter caps; they not only filter out the 120hz hum, they store the energy the amp needs to deliver power chords and hard stacatto notes. Old caps are analogous to an internal combustion engine whose big flywheel is now the size of a glazed donut. Having said that, the Turbine has most of its power in the Velocity term of squarede=mc; Traditional engines have it in the mass term, or the flwheel, crankshaft, etc. This is why I try to distinguish that torque is not a relevant term to use with turbines. Torque will be available with a radical reduction scheme to yield lower rpms, though. kscience says: e=mc2 may read better; the squared was in parentheses after the formula when I entered it........ view all 161 comments http://www.instructables.com/id/Build-a-15%2c000-rpm-Tesla-Turbine-using-hard-drive-/ Jun 29, 2008. 2:34 PM REPLY