Made from an old 4" Sony VTR head that has been begging to be put back in service. I did some drawing on the cad program and discovered that six 1x1x.5 inch N48 neos fit perfectly.
![](http://www.otherpower.com/images/scimages/5769/G4no1.jpg)
There is a machined 1/4" steel backing plate added behind the magnets. The plate also builds up the height flush with the top ring. A close up shows the spacing between the magnet corners.
![](http://www.otherpower.com/images/scimages/5769/G4No2.jpg)
No machining of the head had to be done so the initial balance was retained. My first tests on this setup at 7200 rpm ran smooth as glass. I will do some coil design tests with the head this weekend and post the results. This last picture is a side view and the head spinning.
![](http://www.otherpower.com/images/scimages/5769/G4No3.jpg)
Now to wind some triangular coils.
Joseph.