Hello

I have some minor question regarding the perforation of the stators. You're using a triangle-based tile, which gives a higher efficiency for empty/total area, and also, somewhere in this long thread, there was someone saying that the best/maximum ratio should be 60% (opened area vs total, if I got it right). OK so far, but, from what I see in the pictures all over the thread and mostly "ogling", it shows that the holes are (in general) 2mm diameter and the spacing is (looks like) 1mm. If I am wrong, don't read up the next part

Before I go on, I've tried my hand in some basic geometry and came up with this formula for "x" in the picture: http://tinypic.com/r/102r1cl/9 (can't upload here):

2 * r * { sqrt[ pi/ratio) ] * 1/3^0.25 - 1 }

or, more simplified:

r * [ 1.905/sqrt(ratio) - 2 ]

The ratio is not the percentage but the brute division, as in for 50%, ratio=0.5. This gives the dimension of the spacing required to meet a certain ratio. So, for a 60% opened area and 2mm holes, ratio=0.6, r = 1mm =>

x ~ 1 * [ 1.905/sqrt(0.6) - 2 ] ~ 0.46mm

This can be easily verified with the reverse formula:

ratio = ( 2 * pi * r ) / [ a^2 * sqrt(3) ]

where a = 2 * r + x , which (again, ogling) => ratio ~ 40.3%. Even for a 50% ratio, x should be ~0.7mm, not 1mm.

So, at this point, I'm confused: either the ratio is exaggerated (or I got it the wrong way), or the ratio is good and my ogling should know better. Can someone please provide some measurements for the holes on their stators (and a clarification for the ratio)?

Thank you in advance,

Vlad