## Step 2: Calculations

Before we could begin to manufacture the screw, we had to do calculations for the optimum angle of the screw to sit at and for the pitch of the blades.  For this we referred to 'The Turn of the Screw: Optimal Design of an Archimedes Screw' by Chris Rorres.
Our results gave us 40 blades with a pitch of 30mm and we kept our angle flexible at this stage.

http://www.cs.drexel.edu/~crorres/screw/screw.pdf
hey can anyone post me a mail fpr this i cant get the pics plzzzzz ia m in a seroius need of the archimedes screw and if anyone has another model with metal plzzz plzzzzzzzz plzzzz send it to this mail<em> saisriharsha39@gmail.com</em>
thanks thanks thanks ....1000times... <br> <br>you saved me
You could also seal the outside of the blade to the casing by using it as designed, to pump a small quantity of thick paint (or runny sealant) - this would presumably set wherever the liquid had been.
This is awesome! Good work; Archimedes Screws are interesting. You're lucky to have access to so many tools!
Very nice work,helps if you have all the right tools. <br>If building for actual use,rather than training purposes, you could use an old grain auger for the screw. Also works best if the angle of the pipe is kept between 5 - 15 degrees from horizontal,least amount of slippage.
Thiss looks brilliant welldone!<br><br>High five for all of you<br><br>
Thanks!
This is a very useful Instructable!
Thank you :)
I am by no means belittling your excellent effort BUT you could have achieved the same result, in much less time, with much less equipment and at a much lower cost by wrapping a wide bore PVC tube round a central cylinder. Turning the cylinder cause water to flow up the PVC pipe.<br> <br> <div class="media_embed"> <iframe frameborder="0" height="390" src="http://www.youtube.com/embed/of-14LGhx60" title="YouTube video player" width="480"><br> </iframe></div> <br> <div class="media_embed"> Sorry about the video - suggest turn sound off.</div>
We actually ended up having to do this for the final event so that we had a pump that would run off of our motor, it was always our back up but we didn't try to do it in the beginning because we wanted to challenge ourselves with seeing if we could build the Archimedes Screw. The one you've posted works really well!! Ours worked okay, it managed to lift 5 litres up a height of 60cm in 4.5mins so it wasn't bad. Thanks for the comment!