GuideHardware
3D printing replacement parts: what works, what lasts, what is legal
Printed parts are weakest across layers: Bambu Lab PETG Basic pulls 51 MPa in XY and 35 MPa in Z; Prusament PETG's interlayer adhesion is 18 MPa against 47 MPa flat.
Tagged “home-repair”
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AnswerMaterials
Are 3D printed parts safe for food-contact appliances?
What Prusa Research, FDA 21 CFR 177.1630 and EU Regulation 10/2011 say about printed parts that touch food: layer grooves, nozzle lead, uncertified pigments and coatings.
AnswerHardware
How to match tolerances on a 3D printed replacement part
Design in clearance instead of copying the measurement: 0.15 to 0.20 mm for a snug fit, 0.20 to 0.25 mm sliding, 0.30 to 0.40 mm loose, then check with a tolerance print.
AnswerHardware
Which print orientation makes a replacement part strongest?
Lay the load along the layers: Bambu Lab PETG Basic pulls 51 MPa in XY and 35 MPa in Z, and CNC Kitchen's PLA coupons gained 27 percent tilted to 45 degrees.
AnswerBusiness
Is it legal to 3D print replacement parts?
What utility patents, design patents, trademarks and copyright each cover on a replacement part, the term of each, and how the repair doctrine applies to printing one.
AnswerHardware
How to measure a broken part for 3D printing without a scanner
A digital-caliper procedure for outside, inside, depth and step measurements, with Mitutoyo's ±0.02 mm accuracy set against Prusa's 0.3 mm printer tolerance.
AnswerTroubleshooting
How to remove or straighten a crooked heat-set insert
Reheat a tilted insert at 20 °C above printing temperature (240 °C for PLA) and press it flush, or pull it out on a screw in about 10 seconds; drill 5.6 mm for an M4.
AnswerMaterials
Which filament survives a dishwasher?
Manufacturer HDT and Tg figures for PLA, PETG, ABS, ASA, nylon, PC and PP set against the 150 °F dishwasher sanitize rinse, with margins in °C.