This "enclosure" is designed to nest on top of the Phecda laser engraver machine. Leaving the underside of the machine, with the legs, open to the room. Intended for a 4" duct fan to attach to the top, to exhaust particulates and smoke, blasted off the work piece by the laser head. The duct adapter M3 bolts on to any corner piece, with brass heat inserts.

The colored zones are 250x210mm print bed placeholders. That's how I sized the truss components to fit on the beds, with slot-together junctions, where the print bed sizes overlap.

Requires one thin PET plastic sheet, 16" x 20", cut into four, 4" x 20" pieces. The sheet plastic inserts into the two slots on the corner objects. One larger sheet of plastic goes over the top, and bolts in, with M3 screws into two brass inserts (5mm OD, 4mm deep, M3 threads), in each corner. Then the plastic sheets edges are taped, at the seams, with Gorilla/packing tape. I may decide to design 3D printable objects, to go between the plastic sheet edges.

Update Log:
6/4/2024: Added holes for M3 nuts and M3 screws, to hold the 4x20" PET pieces.
Thickened the "arms" around the PET sheets, and added 2mm of sheet end clearance.
7/28/2024: Added models for a trussed topper, that uses four full $3 PET sheets to seal.
I still need to add the PET sheet mounting holes underneath each piece.
Pieces are designed to fit on a Prusa 210x250mm bed. I have not printed this myself yet.
7/31/2024: New TrussI (rear left) and 4in duct adapter. The duct adapter now screws into the PET plastic sheet, with threaded halves, that slot into and attach to the truss frame.
8/5/2024: Updated all top truss pieces with screw holes, to attach four full PET sheets. For flat truss screws, up to 3mm dia shaft, up 10mm dia pan head, up to 12mm long.