NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
AH - sandwich (working concept)
From: Igor S.
Date: 2020 Mar 4, 15:45 -0800
From: Igor S.
Date: 2020 Mar 4, 15:45 -0800
Here is two photo's of the so-called artificial horizon (AH) "sandwich". Front side is for day and back is for night observations. Base material is 12mm-plywood disc (d = 160mm). 4mm-plywood rings are glued on both sides in order to hold mirrors in place. In the end it is covered with epoxy (colored in light grey).
Front-side is float glass (5mm) which was covered by a black spray-paint at its rear ( it is not exactly what I wanted https://NavList.net/m2.aspx/ novel-material-for-mirror-AH- IgorS.-aug-2019-g45615 but still better than nothing ).
Back-side is a self-made (see my older post: https://NavList.net/m2.aspx/ Home-made-FSM-for-AH- idxmirror-IgorS.-sep-2019- g45840 ) 5mm FSM mirror (it get yellowish with time but for night sights it really does not matter).
Both mirrors (d = 130mm) were cut with circular glass-cutter from pieces which I got for free from a local glass distribution company (discarded glass).
Mirrors are centered inside the plywood rings with some little space in between. This space was filled with a black rubber-like glue to hold mirrors in place permanently.
AH resides on three M3 brass screws (sharped at one end). The knob is a piece of brass tube (13mm) filled with lead.
Thread for the screw inside the plywood is created by filling a drilled cylindrical hole (bath) of a bigger diameter with thickened epoxy, while the body of the screw is positioned in the center of the bath. Upon solidifying it creates a thread which match with the screw perfectly. This creates a tight fit so that the screws move strictly in vertical direction.
NO tap or metal M3-bushing/spacer is required !!!
Leveling is performed with the help of circular bull-eye level (from www.leveldevelopments.com) by placing it at the middle of the mirror face.
kind regards,
Igor