This project is for you if you are looking for an inexpensive fixed framed screen and have patience.

BOM:

• 2x  Alu U Profile 20x20x1,5 mm / 2m - cz store link
• 2x  Alu U Profile 20x20x1,5 mm / 146cm - (Just buy two more 2m profiles and cut them)
• 4x  Alu U Profile 20x20x1,5 mm / 27cm - (cut the remaining profiles in half)
• 2x  Alu square tube Profile 20x20x1,5 mm / 1m - cz store link
• 40x 5x5 M3 heat inserts
• 40x M3 10mm flat head screws
• 11m M3 VHB 5952F 19mm - yes it a lot and its not cheap but its good stuff
• 2x screws to the wall (i used Fischer N6 x 60/30 mm S)
• 2x 100" White grid projection screen from Ali (one is just too thin, or you can use different fabric as first layer, or maybe some dark foil) - ali, test of the screen fabric: youtube
• 3D printed parts - use 4 or 5 walls and 25% or more for infill
  • 4x corner-joint
  • 4x 45-brace-joint
  • 4x 45-brace-joint (mirrored along y axis, look at images)
  • 4x brace-joint
  • 2x wall-mount
  • 2x profiles-drill-guide (one is as spare)

Short how to (for more guidance look at images)

1. Cut profiles to BOM specification
2. Drill profiles with drill guide (there are two hole spacing's, closer together are used for brace joints and further away for corner joints, drill holes in same face !)
3. Push heat inserts to the 3d printed parts (flushed with the walls as possible)
4. Screw together frame (ideally on floor, too much flex can break 3d printed corners)
5. Screw together 45-brace-joint and 27cm U profiles
6. Screw together brace-joint and 1m square tube profile
7. Apply M3 VHB tape to brace joints, on slightly recessed faces (before apply, use IPA for cleaning)
8. On main frame clean inside the U profile with IPA
9. Guide and push corner braces (45) in to the frame (repeat in all corners)
10. Guide and push big braces in to frame, each one about 80cm from corners of the frame.
11. Now you can flip frame on back and use M3 VHB (not on whole frame just 10cm tape strip every 20cm) on front to secure first layer and cut it around the frame (its a pain job, maybe you can use black foil with adhesive as better replacement)
12. Now you can apply tape on side of the frame and around full frame.
13. Prepare white grid fabric (use iron and steam for flattening it as much as possible, give it time)
14. Secure fabric at the top first. Then try fix the frame as much possible and on opposite side try stretch it and stick it to the vhb tape, go slowly max. 50cm at time.
15. Now you can try sides with same technique, look from the side for ripples and try tension it. Additional hands are always useful. Dont rush it.

Its not the best design but it works and final price is around 110 euro. But if you are not that crazy you can buy 100" Aveli (EU) for about same price and if you want to use white grid fabric, just buy 120" variant and try stretch it on Aveli frame