LESTRADE 3D Stereoscope (Stereo Viewer)

Hi,After buying some 3d stereoscopic cards in a second-hand shop, I purchased on internet a used Lestrade stereocope.Instead of buying a second stereoscope in order to offer it to my niece, I decided to design my own stereoscope. This explain why I used the pink color for the one I printed ! Here a website explaining the 3d stereoviewers : 20th Century Stereo Viewers - www.viewmaster.co.uk, and the version that I use : Lestrade Stereo Viewers (viewmaster.co.uk) or Lestrade Standard & Simplex Stereo Viewers | 1950s 1960s 1970s France — Vintage 3D (vintageviewers.com) Here a example of the Lestrade cards : Design and chooses :I haven't design a bracket or level to scroll down the card (like there is on the original Lestrade stereoscopes), so you will need to do it by hand (pushing from the top or pulling down from the bottom).There is a “clic" system to stop the card each step where there is a picture to look at. This system is made of 4 magnets (2 stacks of 2) and two CHC screw