JP ASTROCRAFT, LLC.   

The Twenty-Five    Sweet 16's     Custom Mirror Cells     Custom Projects     Telescope Page    Contact

 

 
Welcome to JP Astrocraft, my little astro manufacturing company.  I'm John Pratte. I spent over 40 years as an engineer for a large manufacturer.  I recently retired and can now devote more time to my telescope making activities.  I've made telescopes for over 50 years, including mirrors up to 20 inches.

 The Sweet  Sixteen
In my search for the perfect size personal telescope, I designed and built a 16" F4 which became nicknamed the "Sweet Sixteen".  Well, actually I built four.  Two are currently available for sale.  The 16" aperture provides enough light gathering, and the F4 optic allows an eyepiece height of about 62" at the zenith.  The compact design is several inches smaller than most other 16" scopes.  Refer to the telescopes page for specifications and construction details.  You will see why I am proud of the Sweet Sixteen.  It is available with a mirror from Mike Lockwood or Dick Wessling.

 

For the discriminating observer desiring more aperture than the Sweet Sixteen, we are introducing The Twenty-Five. Same fine craftsmanship, more innovations. Click on The Twenty-Five tab to see all the details.


Three focal lengths

The Twenty-Five is available in (from left to right) an f/5, f/4, and now the "No Ladder" f/3 configuration. All feature Lockwood primary and matching  secondary optics.

20 Inch Tip-out Mirror Cell

 Custom Mirror Cells
I have also built a number of custom mirror cells over the years.  My cells mount the mirror on it's own support framework and use a pivoting support at the mirror edge to prevent binding. I do not believe slings or glued on supports are the best way to support the edge.  The larger cells feature spherical bearings at the support triangles to reduce slop in the pivot.  The sweet sixteen cell uses channels that are shaft mounted for the levers, further controlling slop.  This frame is spring loaded with stainless Belleville washers to the mirror box frame. This construction results in a strong, easily collimated cell that resists collimation change as the scope is moved while properly supporting the precision optic.

 

 

Partial View of Machine Shop

Custom Projects

I was fortunate enough to have acquired a reasonably complete machine shop for my telescope making activities.  It is great to be able to make the proper part for a scope rather than having to adapt hardware store or commercially available parts.  See my shop section for  my equipment and custom projects for pictures of special stuff I have done.
 
If you are interested in a finely crafted "Sweet Sixteen" telescope, special mirror cell, or have a unique need please contact me at:

astrocrafter[at]consolidated[dot]net.

 

Thanks, John

The Twenty-Five     Sweet 16's    Used Telescopes    Custom Mirror Cells     Custom Projects     Pricing     Contact