331 Mirror Array (Approximately 22.5" focal point) divided to fit Ender 3 bed)

thingiverse

CAUTION: MAY CAUSE EYE DAMAGE OR FIRE. USE AT YOUR OWN RISK! Update 6: 12/15/2021 I printed out three parts: alternate_border6, triangle5, and alternate_border_hub_small_hole. I hadn't noticed it earlier but I found a fitment issue related to the perimeters that wrap the bases of all three parts. It is too wide for proper mating of adjacent pieces... The problem is that the individual mirror cells overlap and when I separated the cells into parts of the larger array, each cell along the perimenter got the full width base perimeter border and so they bump up against each other instead of overlapping as they do in the model. One solution would be to eliminate the base overhang on the six alternate border pieces because it the alternate border pieces that connect to the triangles and the alternate_border peices also all connect to the hub. The problem with this is that the six alternate border pieces meet on one cell face so eliminating the base perimeter border overhang will leave a gap so it is likely better to get rid of the perimeter base overhang on the triangles and hub. The triangles and the hub do not touch each other so there is no issue there I do not believe. Another solution would be to plane cut the stls horizontally to separate the bases and just scale the bases down for all the pieces so that when reconstructed, the pieces butt up against each yet still have proper mirror alignment... I'll give it some more thought. Update 5: 12/14/2021 I used just 4 mirrors glued on to alternate_border6 to more accurately measure the focal point using sunlight through my window. I held alternate_border6 to concentrate the light on my white vinyl window frame. The focal point looks to be ~22.5" to the mirror closest the center on alternate_border6. The light scattering from the my target (a white vinyl window frame) from JUST four mirrors is enough to leave a hexagonal image imprint visible when I close my eyes similar to if I had just looked at the Sun. I have no doubt that when any part of this array is loaded with mirrors it undoubtedly could damage your eyes from just the light scattering off a target (PROTECT YOUR EYES!) Update 4: 12/13/2021 I printed out alternate_border6 and upon initial observation (I placed 8 mirrors oriented the assembly so that all mirrors reflected the same recessed light), they reflected nicely however it appears that the focal point is at approximately 24 to 27 inches high, not the 12 inches that I anticipated (update: Measured focal point using sunlight was closer to 22.5"). I'll need to confirm that via more testing. It still looks like it will still work but the focal point distance appears to be twice what I had expected... Thinking about it more, it is because I generated the array with a 12 inch focal point and then uniformly scaled the array up to 150% of its original size to fit 1 inch hexagonal mirrors. Since the angles of the mirrors didn't change after scaling but the perimeter of the array larger, then the focal point would move up... hmm... The array had a point-to-point diameter of 362mm before scaling up to 150% scale which then became 543mm excluding the base rim. This would make the scaled focal point 18 inches (but I have now measured it using four mirrors and sunlight at approximately 22.5 inches). Update 3: 12/12/2021 I divided the six borders and the six triangles into seperate stl files to fit on an Ender 3 bed. I decided to use the alternate (longer) border with alternate (smaller) hub. There are several alternate hub choices depending on whether you want a hole in the center or not. Print as as many pieces as you'd like. I will be printing parts to test myself shortly. I'll probably start with border6, triangle5, and one of the alternate hubs to start with. I recommend printing the alternate hub at a lower layer height for more mirror support since the angles are not very steep in the middle of the array. The (6) alternate borders have 24 mirrors and the (6) triangles have 28 mirrors. The alternate center hub can have up to 19 mirrors. Don't burn yourself or damage your vision as this can be very dangerous! Keep your eyes away from the focal point to avoid vision damage/blindness and be careful that it is stored out of sunlight. Update 2: 12/12/2021 I ran into a couple issues with some mirror cell bases not slicing correctly on the borders after splitting up the sections. Repairing the stl in Fusion 360 via "Wrap" resolved the issue. I posted the six border files that have been separated and repaired which I see slice correctly now. Update 1: 12/12/2021 I added an alternate longer border and smaller hub options that I like better than the original shorter border and larger hub. The alternate borders do touch their adjacent borders on one hex face but it makes the hub smaller. As the focal point is 12", the hub would benefit from being printed at a lower layer height for precision and it is smaller this way saving print time and it should be easier to align the borders. The wedge slices do not change. -- These are the parts of a 331 (or less; you choose) mirror array that was separated into chunks to fit the pieces on an Ender 3 or Ender 5. The focal length is 304.8mm or 12 inches above the center of the array. I created a few options for the hub which could be printed at a higher quality than the rest which may help with mirror alignment. Keep in mind that the mating parts have no tolerance built in. It is easy to plane cut the meshes apart in Fusion 360 and is the next step to fit pieces onto print bed. based on my mirror array experimentation here: https://www.thingiverse.com/thing:5158449 and https://www.thingiverse.com/thing:5162096 All of which is very much derived from the excellent design here: https://github.com/bencbartlett/3D-printed-mirror-array My first Thingiverse page above is cluttered so I created a new thing specifically to capture files relevant to this particular experiment.