Roof Mass Ledger R1.

Research record

The detail behind
the study.

Source-linked work for this revision. Reported checks describe the stated model or test; physical qualification and applicability to the current retrofit remain separate.

Roof-frame mass and clearance ledger

At the current 6 mm reinforcement allowance, the nine frame members contribute 44.29 kg and the six wraps 14.35 kg, using the source study's assumed 1560 kg/m³ density. The modeled bondline adds 0.90 kg at a separately assumed 1200 kg/m³.

The frame-plus-wrap subtotal is 129.26 lb, leaving only 3.04 lb in the old 132.3 lb allocation for the complete structure. This is insufficient evidence that the center support, rim, wall/base frames, partitions and hardpoints can fit that allocation. The former 451.9 lb whole-tank planning total cannot be carried forward as the current design's weight.

The finished conservative opening remains 931 × 547 mm before a collar, seal or closure. The 3 and 4.5 mm cases show sensitivity only; neither is a selected or strength-verified alternative. No thickness may be reduced solely to recover weight.

The ledger measures CAD solid volumes, not manufacturing waste or weighed parts. Resin-rich zones, corner fillets, ply transitions, skin, seats, hardware and protective layers are not silently included. Adhesive mass uses an estimating assumption pending material selection. This is a partial estimate, not a BOM or a complete tank mass claim.