Printed lid

FAILS. Warps 3.81 mm off flat, over the 0.8 mm tolerance, with a corner lifting 3.81 mm when it comes off the bed. Confidence: medium. process estimate: the warp model is fitted to 48 measured ABS plates (median error 9%, worst 39%)flatness: 3.81 mmtolerance: 0.8 mmcorner lift: 3.81 mmstress on the bed: 15.8 MPa Checks:  [pass] mesh convergence: flatness after release settled: 3.79 -> 3.81 mm over 2 meshes, last change 0.4%  [pass] hand calculation: a free plate 14.5 mm thick with the same shrinkage curves to 0.557 1/m, 3.62 mm over its 220 by 60 mm footprint; the solve gives 3.81 mm (1.05x)  [pass] balance on the bed: the shrinkage loads itself, so the bed's pulls and pushes cancel to 1.6e-08 of 9654 N  [pass] units and sanity: locked in shrinkage up to 0.72%, largest movement 7.57 mm on a 220 mm part  [fail] flatness: the face on the bed comes off 3.81 mm out of flat, its corners up to 3.81 mm, against a 0.8 mm tolerance  [info] bed peel: while it prints, the corner at (220, 0) mm pulls up on the bed with 336 N, about 0.365 MPa over its 34.2 mm patch Assumptions:  - Wobbl guessed: bed temperature not given, so Wobbl assumed 100 C, usual for ABS.  - Wobbl guessed: no enclosure mentioned, so the part cools in open air at 25 C.  - Wobbl guessed: print direction not given, so the part prints the way it is drawn, layers along z.  - Wobbl guessed: infill not given, so Wobbl treated the part as solid, as the calibration plates were.  - ABS: E 2200 MPa, Poisson's ratio 0.35, expansion 90 per million per C, glass transition 105 C. Tg typical of ABS (Stratasys ABSplus lists 108 C); warp ramp fitted to Armillotta et al. 2018.  - Printed with layers along z, into surroundings at 25 C (an open printer).  - Each layer locks in the shrinkage from the glass transition to the surroundings, up to 0.72%, rising from nothing at the bed to all of it 11.5 mm up, a profile fitted to the 48 ABS plates of Armillotta et al. 2018 (R2 0.94).  - The part is held flat on the bed until the print ends, then released; corners that peel during the print are not followed, so a part that lifts early warps more than this.  - The part is solid.  - Supports, the seam and the cooling fan are not modeled, and the layers are treated as one bonded solid.  - Predicted 9 min for the first 2 mesh levels against a budget of 10 min, so the meshes were left as they were. It solved 2 levels of 26,082, 52,070 nodes in 3 min. The budget can be raised with --budget. Suggested fixes:  - Print in an enclosure near 45 C: The locked in shrinkage runs from the glass transition down to the air around the part, so air at 45 C instead of 25 C cuts the warp to about 2.86 mm.  - Print it in PETG: PETG locks in 0.33% against 0.72% here, for about 1.75 mm of warp, if its strength and heat resistance suit the part.  - Add a brim and keep the bed hot: While it prints a corner pulls up with about 336 N. A 5 to 8 mm brim gives that corner more bed to hold, and a bed near 100 C keeps the first layers soft and stuck, which this model assumes; it does not change the warp after release. Images: warp: images/warp.png, stress: images/stress.png, flatness: images/flatness.pngReport: report.html