The SPA Telescope


9. Make Mirror Clips


Make wooden clips, with slot slightly larger than mirror thickness. Check tube and mirror diameters to find 't'; allow 1 mm extra distance so as not to grip tightly. Glue felt to inside of slot.

10. Drill clips


Drill 1 mm holes in backs of clips to take 3/8 in. No 2 woodscrews. Assemble in place in tube, without mirror, to check they are secure.

11. Install mirror


Locate clips in appropriate places around mirror and push home. Do up loosely.