A common method of hanging stained glass panels in front of windows involves the use of chains attached to the panel frame and to an overhead support. However, a need to hang two fairly heavy ( 11+ lb. ) panels incompatible with conventional mounting hardware and techniques in front of preinstalled and prefabricated (metal and vinyl) windows with unknown framing structure called for a different approach.
Here, we use custom 3D printed mounting blocks supporting aluminum C-channels. The stained glass panel rests in the lower length of channel and is held in place by an inverted duplicate channel above the panel. The mounting blocks are secured to the window frame via screws driven into the 1/4-round trim surrounding the window.
The channel mounting block was designed in Autodesk Fusion 360, sliced in Cura with a 40% infill for added strength and printed with PLA. It features a concave corner surface to accommodate the 1/4-round window framing trim, a 0.55 in. deep rectangular cavity to support the channel ends, and fillets for the caulking surrounding the trim. Of course, the features and dimensions of the STL file below can be modified to suit individual requirements.