Dobsonian Telescope Collimation Cheshire Eyepiece

This is a very useful tool to Collimate your telescope. You can add some tin foil to the diagonal to make it more visible. or paint it white. I just used glue stick and some aluminum foil.   

To get the Cheshire to print well. I added a modifier in Cura to print at 20% speed for those few layers. Depending on how well your printer bridges this may be unnecessary.  Just pull it down through the bed in the slicer if you want to test print it. 

Designed for 0.2 layer height. but just look at the way the slicer is printing the cross lines, and make sure it's not going to be thinner lines than the nozzle width. And it should be fine at other layer heights.