# Micro turbine



## Florian (Sep 10, 2008)

Hi together

I think its time to show you my newes project: 

Some time ago, i've had an idea how to make the turbine blades on a turbine wheel. Of course, everyone who has a cnc-mill can make them. Or you can build some special tools to make them. But i wanted to make them without cnc and without additional installations. 
What came out is a special cutting bit which makes the shape of the single blades.
I made it from silver steel and hardened it after machining. The first one broke after 14 cuts because i forgot tempering. 

Now here's the second version:
4mm outer diameter, 3mm inner diameter (first version: 5/4 mm). 












And here's the first "turbine wheel":





Here you can see where the bit crushed:






Now, here's the next wheel. Unfortunately i made a dividing error and the wheel is not usable. 





And finally i managed to machine a complete turbine wheel: 











Just to show you the size of all these things:





What i can say, is that this method allows you to produce a turbine wheel with quite few efforts. I only needed 15 minutes to complete the cutting bit and another 15 minutes to get the turbine wheel. 

Florian


----------



## Florian (Sep 10, 2008)

Hi again

I also machined a casing to get the turbine working:






The hole is where the compressed air (or lateron the steam) enters the jet:






The rotor is finished now and fits tightly into the ball bearings. 





This is how it looks when assembled: 





And the back side:







I have also uploaded a video where you can see or rather hear the turbine running. 
[ame=http://www.youtube.com/watch?v=BL2kg3QS8j0][/ame]
hint: hit the "watch in high quality" button below the window, on the right side.

The rattling noise at the end of the video is my compressor which is actually an airbrush compressor. 




Florian


----------



## kustomkb (Sep 10, 2008)

very clever, sounds great too!


----------



## Divided He ad (Sep 10, 2008)

Now that is cool! Would you be able to make a short vid' of the blade being cut please Florian? 
I would like to see the process, Then I can try it myself ;D 

Even a few pic's of the tool and blade in position would help me get my head around it 




Ralph.


----------



## Florian (Sep 10, 2008)

Hi Ralph

Yes, of course i can make some pictures of another blade being cut. And also a video. As i said, its very easy to do it. 

Florian


----------



## Bogstandard (Sep 10, 2008)

Florian,

Very nice indeed, those small ones sure get up to high RPM.

I was looking on one of the links to bearings that someone had put on, and found some ceramic hybrids that are guaranteed to 300K + , at a very reasonable cost. The limitations on the ones I make is the bearings. Can't chance it over about 45K.

John


----------



## BobWarfield (Sep 10, 2008)

Looks and sounds great. That's a clever bit of tooling to make it too. Even a CNC would make it a lot faster with one of those!

It's not unlike Wes's steam siren in many ways.

Cheers,

BW


----------



## dparker (Sep 10, 2008)

Hello All: That is a really nice model and is quite impressive sounding. It brought back memories of when I was first introduced to model engineering and still single so I bought up most any books that interested me. One of the books was "*Model Steam Turbines" by H. H. Harrison * The "Model Engineer" Series No. 23 from MAP Publications. This book has multiple turbine model designs in it and one of the designs is quite similar to this post. The type cutter Florian shows is somewhat discussed in one chapter of the book. Some day I would like to build a small turbine and this will go on my list of to-do models should I ever live long enough to do all the great ideas I see on this forum.
THANK YOU FLORIAN FOR BRINGING UP OLD WISHES AND DESIRES!
THANK YOU RICK FOR THIS FORUM!
don


----------



## CrewCab (Sep 10, 2008)

That's a neat bit of tooling, and engineering ............. from where I'm sitting 

Florian, I'm with Ralph ................. video would be great 8)

Thanks for sharing the "OUT TAKES" too  ............. it makes us all feel better 

CC


----------



## Kludge (Sep 10, 2008)

I love it!  :bow:

The only thing I can think of that's smaller is a dental drill turbine and I think yours has more torque. OR it should. Of course, now that you have a single stage turbine, you have to start on a multistage. ;D

BEst regards,

Kludge


----------



## Divided He ad (Sep 10, 2008)

Thank you Florian, it will be much appreciated ;D




Ralph.


P.S. Dave.... 





> Florian, I'm with Ralph ................. video would be great


 it's a good thing we know in what context!!!! :big:


----------



## rake60 (Sep 12, 2008)

Very well done!

Rick


----------



## Paul (Nov 25, 2012)

dear florian,
 i am very interested in the turbines you are making for a rc vehicle for my little one, if you wouldnt mind giving me so information on how you build your awesome projects, id really appreciate the help, if you could email me at [email protected] it would mean a lot,
                                                                            Thanks,
                                                                                     Rob


----------



## charlesfitton (Nov 26, 2012)

...but I cannot find the video, which I really want to see.

thanks for the great inspiration.


----------



## skyline1 (Nov 26, 2012)

Hi Florian

Smashing little job.
That looks like a Stumpf type rotor and they are capable of quite phenomenal speeds. In fact I believe (might be wrong though) that the fastest ones ever made were Stumpf type and went in excess of 250,000 R.P.M.

I am also a turbine enthusiast, I find them fascinating, like yourself I suspect, A little scary though especially at full speed.

The main problem with them appears to be getting bearings that can cope at these high speeds and I would be interested to hear what you use

Mine are DeLaval  Turbines which are somewhat slower (and larger diameter) than yours (about 30,000 RPM.) I use small ball races in my latest one but have had great success with plain bearings made believe it or not from Cast Iron.

I fabricate mine but with the small rotors and high speeds you are using milling them from solid, as you have done, is probably the best way to go

A picture of one of mine for comparison. the rotor is 2 1/4" Dia




Nice to see a fellow sufferer from "turbinitus"

Regards Mark


----------



## abby (Nov 26, 2012)

Hi , I too am interested in steam turbines and am attempting to turn this dummy generator into a working model.




 I have only 25 mm available for a rotor but would like to generate enough power to at least light a couple of LEDs.
I was thinking of two rotors and a static between , has anyone any ideas?


----------



## skyline1 (Nov 27, 2012)

Hi Abby

It is perfectly feasible to make small turbo generators I have two of them. Even with a 25mm rotor you should be able to light a couple of LEDs with ease. I would think more like half a dozen. Mine which admittedly are quite a bit bigger Can produce about 4 Watts, enough to drive about 40 LEDs

Here's a pic of one in action.




I don't want to hijack Florian's thread though so if you would like  some further info please P.M. me or perhaps we could start another thread on the subject

Regards Mark


----------



## modeng2000 (Nov 27, 2012)

Excuse me for butting in but a new thread would be most helpful.

John


----------



## d-m (Dec 2, 2012)

Florian
Vary interesting turbine I am hoping to see more on this build. I also can't seem to find the video thanks for sharing.
Dave


----------

