THE COLLECTORS LOUPE

The “collectors Loupe” was designed as an object for the adventurous at heart. Presenting itself in the form of an ancient temple or rotunda, the small building conceals a 10X triplet loupe as well as a timepiece in the roof top. At rest this small wonder begs further investigation drawing us in  as a curiosity. Once revealed, the temple becomes a beautiful tool with a wonderful 19C flavor and playfulness.

The loupe is entirely handmade in 18K gold and platinum with hardened and blued steel screws and springs. A cabochon sapphire is set in the crown and just to the right of it is a small diamond push piece to open the roof top, revealing the watch. The loupe measures approximately 45mm wide by 55mm high. steel embossing dies were made for the roof sections which emulate tiles.
   The exploded view shows the 45 components that make up this piece. With an average of two parts per component, that makes a total of roughly 90 parts to be made and assembled.

   The dial is engine turned silver with gold chapter markers. The threads on the barrel for the optics were thread milled, a process which I will discuss in a later posting. The hands are handmade, hardened and blued. All flat surfaces were hand lapped to a final polish, as the polishing wheel cannot impart a "mirror finish".


   This piece has been time well spent at the bench and the rewards were great, from the engineering aspects to the final assembly.
  The Collectors Loupe is yet unclaimed, and available for purchase.


 

WATCH CASE THREAD CUTTING

   The need to chase threads on a watch case or any other item can be a challenging proposition. Most instrument lathes have little or no thread cutting appliances, and if they do, the limitations become apparent immediatly. I needed a simple and accurate piece of tooling to achieve this and my attention was drawn to a memory of a sort of thread-follower set-up I had seen in an old engraving. I set to work developing this attachment to fit the Derbyshire 10mm Elect. This tool took roughly fifteen hours to complete.

   A brief description of the tool is as follows. A bushed carrier is mounted to the lathe bed behind the headstock. In the carrier, a ground rod is able to slide with great ease and precision. On the far end of the rod is mounted a slide with a tool post, in the tool post, a hardened and ground thread follower is mounted. This follower rides against a threaded die that has been mounted on the headstock spindle. On the other end of the rod is the cutter arm. As the whole assembly is rocked forward, the follower picks up the threaded die and carries the rod with the cutter towards the headstock, creating an identical pitch thread on the work. As the follower slide is withdrawn, a deeper cut is made, this is the tool in-feed.

   The beauty of this attachment is in the threading dies, any pitch can be made, and the die is made very quickly on a good toolroom lathe. The other advantage is the speed of set-up for any given piece of work. I have made dies with 80tpi that will reproduce very nice threads such as those found on camera lenses.
   The piece being made is a giant 22 size wristwatch case. I will be posting more on this watch again.