The inlet nozzle is one of the most critical items of the Tesla Turbine. This is because the nozzle shape determines the fluid velocity, and  the fluid velocity SQUARED determines the power of the turbine.

So, fluid velocity is very important. The fluid velocity can be increased (up to a point) by using a smaller hole for the inlet nozzle. The exact nozzle size is determined by the number of discs used, the pressure and volume of fluid available, and whether air or water is the fluid. So, for example, a 1/16 inch to 1/8 inch nozzle hole size might be appropriate, but a 1/2 inch hole size probably won't work at all.

The magnets can be bigger, but quality usually beats quantity. Big magnets means more internal resistance inside the turbine, which might result in less power. I use the N50 grade neodymium magnets which are very powerful. The lighter the magnets, the better for turbine performance, but they aldso must be strong enough to work as a magnetic coupling for the device you are connecting to such as the generator.

Good luck with your turbine and let me know if you have other questions!

The "Orbit Watermaster" is simply a tapered plastic nozzle that goes on a pipe. It's used to flush out dirt or move gravel.

As long as your pipe ends with a 1/16 inch hole size directed at the discs, that is the most important thing. It doesn't have to be a tapered nozzle, but tapered is more efficient. Drilling a 1/16 inch hole into a pipe plug at the end of the pipe, would work too. Or you can glue or screw smaller pipes together to reduce them to 1/16 inch opening.

Increasing the number of CD's will increase power up to a point. You need to have a few discs (say, 5) as a minimum.

Any problems can be solved through communication ;)
Have an enjoyable learning experience!

Tell me more about your project turbine. Did you add discs to the turbo shaft? Lots of turbos spin over 100,000 rpm and some of them go up to 220,000 rpms! Any pictures you could post?

The magnets have several functions. The smaller 1/32 inch thick magnets are used as spacers between the discs to maintain the optimum disc spacing and for ease of assembly. The larger 1/2 inch neo magnets on the top disc of the turbine are the drive magnets to enable an external magnetic coupler to turn by the magnetic coupling. Also, the magnets are a rotating magnetic field, which can be used to obtain electrical power from the turbine as an alternator directly. And, finally, the magnets are also part of a plan to magnetically levitate the turbine disc pack, thereby enabling a bearing-less, shaft-less and seal-less turbine! This is not free energy, and is like any air motor in the sense that it will require more power to run it than what you get out. The air compressor will need more energy to compress the air than what comes from the alternator. The Tesla Turbine is an underdeveloped design whose time will come again because of the modern materials available today. I believe it has the potential to be the lightest, most powerful and efficient fueled engine possible. Thanks for your interest! Any more questions let me know.

I was forced into it! Seriously! I developed severe allergies to my work as mechanic, lost my business and declared bankruptcy. I spent my last few dollars on magnets, to try to rebuild my life doing something different. I made a decision to be an inventor of magnetic things, and to promote the name of Tesla, and the Tesla CD Turbine was born! I've always wanted to be an inventor, but was too busy working to follow my passion. Sometimes having your life turned upside down can be a good thing!

The 1/8 inch cubes were N48. The 1/4 inch spheres at the top of the inside disc pack were N38. The magnetic coupler I first used had 3 of 3/4 x 3/8 inch N42 neodymium magnets. I currently use 3/8 inch x 1/32 inch N42 spacer magnets and 6 of 1/2 x 1/2 inch N42 top magnets. The current magnetic coupler uses the same 1/2 x 1/2 N42 magnets. Generally, I would go to stronger magnets (N50) for heavy-duty use...and weaker for kids or less demanding applications.(N38)

rimar2000, I have 3 instructables on this device, with lots of pictures, words, and videos:
Build an Amazing Tesla Cd Turbine
and Tesla CD Turbine With Scary Steampunk Laser PumpkinCutter Attachment
and
Turkey Time Tesla CD Turbine .

I made this video before my 3 instructables. It shows the initial thought process for inventing and prototyping. Guess I'm an idiot for thinking it would be appreciated. I guess intelligence isn't your specialty, either.( "instructuble" is spelled "instructable".)

Hmmm, good constructive idea, rimar2000. Thanks, I'll think about that!