I have a 6″ can light installed in the ceiling, which has been working fine. But I have been upgrading all my bulbs to Nanoleaf Matter controllable bulbs, and they only make a 4″ canless downlight. This, of course, does not fit into a 6″ hole. I could repair the hole, but then I’d have to cut another smaller hole, which would be a problem as drywall repair for larger holes uses a metal mesh to hold all the goo in place. So I think this is probably a fairly typical situation, and I’ll just pick up an adapter plate. It turns out I was wrong. I was not able to find an adapter to do it. And since necessity is the mother of invention, I decided to make my own solution. OpenSCAD to the rescue. When printed, it’s a snug fit; you can adjust the value of light_hole if needed.
// Recessed light adapter plate for Nanoleaf 4" downlights (and other 4" canless lights)
// v2024111101
// by Scott Garrett
// Sizes in mm
light_hole=104;
outer_ring=185;
inner_ring_height=22;
wall_thickness=3;
difference()
{
// Create a circle the size of light_hole plus wall_thickness
cylinder(h=inner_ring_height,r=(light_hole/2)+wall_thickness,$fn=128,$fa=0.01,$fs=0.01);
// Subtract out the base size, leaving a hole the size of light_hole
cylinder(h=inner_ring_height,r=light_hole/2,$fn=128,$fa=0.01,$fs=0.01);
}
// create a circle, and extrude it. the scale call creates the sloped edge to make it look prettier
linear_extrude(height = wall_thickness, center = false, convexity = 10, twist = 0, $fn=128,$fa=0.01,$fs=0.01,scale=[1.025,1.025])
difference ()
{
circle(d=outer_ring,$fn=128,$fa=0.01,$fs=0.01);
circle(d=light_hole, $fn=128,$fa=0.01,$fs=0.01);
}