Possible source of 3 3/4 inch flat mirrors: a dead hard drive

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  • Member since
    March, 2009
Possible source of 3 3/4 inch flat mirrors: a dead hard drive
Posted by wa2ise on Monday, February 17, 2014 4:55 PM

Anyone who has had computers for the past 15 or more years have or had old computers where the hard drive has died, or just obsolete.  Taking a hard drive apart, you'll find one or more disks where the data is stored.  As the bits are very tiny, and the disk/s spin very fast, they need to be very flat and smooth, kinda like telescope mirrors, though telescope mirrors also are curved.  To my untrained eye, most hard drive disks look chrome colored and I don't see any distortions.  These disks have a 1 inch hole in the center.  Maybe you could use one for the diagional mirror for the eyepiece...  I don't know if you can cut these without bending them. 

Tags: flat mirror
  • Member since
    August, 2010
Posted by PeakOilBill on Tuesday, February 18, 2014 4:47 AM

Even if you could cut them, the cutting would probably result in them being distorted. They are a lot thinner than flat telescope mirrors, so keeping them perfectly flat in a telescope would be difficult, if not impossible. And because something looks reflective, doesn't mean it is reflective enough to use efficiently in a telescope. Those little suckers are expensive for a reason. But I'm no expert. It might work. 

I would love to see someone mold a plastic telescope mirror then overcoat it with metal. If that could be done, big telescopes could be made cheap enough for the masses. 


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