Activity 002: Supervised Resin Print Execution

Activity ID: U2M3-ACT-002 Duration: 45 minutes Objective: Students will execute a complete resin print from file preparation through print completion, performing all safety and quality checkpoints. Group Size: 2-3 students per printer (instructor supervision required) Materials Cost: ~$3-5 (resin for small print)

Overview

Students apply their slicer skills to prepare, start, monitor, and complete an actual resin print. This is a hands-on execution activity where each student performs specific roles (file preparer, machine operator, safety/quality monitor) and rotates through each role. Instructor supervision is mandatory throughout.

Materials & Equipment Needed

• MSLA resin printer (one per group, instructor-supervised)
• Standard resin (405nm, pre-filled in vat by instructor)
• Provided or student-prepared STL file (small model, <30mm tall, <20 min print time)
• Resin slicer software on computer
• Nitrile gloves (multiple pairs per student)
• UV-blocking safety glasses (one per student)
• Lab coats (one per student)
• IPA wash station (for post-print)
• Paper towels
• Scraper/spatula
• Print execution checklist (printed, one per group)

Instructions & Procedure

Phase 1: File Preparation (10 min) Role: File Preparer leads, others observe and verify

1. Import the STL file into the resin slicer
2. Orient the model at 25-35° tilt to minimize peel forces
3. Hollow the model if wall thickness exceeds 4mm (2mm wall, drainage holes)
4. Generate medium supports with 0.4mm tip diameter
5. Manually review supports: remove from critical surfaces, add where needed
6. Set exposure parameters (use manufacturer recommended settings or calibrated values)
7. Set layer height to 0.050mm
8. Slice and export the file to USB drive or send to printer via network
9. Record estimated print time and resin volume on the checklist

Phase 2: Pre-Print Setup (5 min) Role: Machine Operator leads, Safety Monitor verifies

1. All students don PPE: lab coat first, then safety glasses, then nitrile gloves
2. Safety Monitor verifies: ventilation on, eyewash accessible, SDS available
3. Machine Operator inspects the resin vat:
   • Check FEP for damage, scratches, or stuck cured resin
   • Verify resin level is 40-60% of vat capacity
   • Gently stir resin with the provided silicone spatula (NOT metal)
4. Machine Operator inspects the build platform:
   • Clean and dry surface
   • Properly leveled (verify level procedure was performed at start of day)
5. Load the print file onto the printer

Phase 3: Print Execution and Monitoring (20 min) Role: Safety Monitor leads monitoring, all participate

1. Start the print from the printer's interface
2. Layer 1-3 checkpoint (first 2 minutes):
   • Listen: gentle suction release is normal; loud pops indicate excessive peel force
   • If using a transparent vat, observe the first layers forming
   • Record: "First layers started successfully" or "Issue observed: [describe]"
3. Layer 5-10 checkpoint (minutes 3-5):
   • Pause the print briefly
   • Tilt the vat slightly to check if material is adhering to the platform
   • If nothing on platform → cancel immediately, troubleshoot
   • If part visible on platform → resume print
   • Record checkpoint result on checklist
4. Mid-print check (every 5-10 minutes):
   • Listen for unusual sounds
   • Check resin level visually
   • Look for any cured debris floating in the vat
   • Record: "Print progressing normally" or describe any concerns
5. Continue monitoring until the print completes

Phase 4: Print Removal (10 min) Role: Machine Operator leads removal

1. Once the print finishes, allow the platform to remain raised for 2-3 minutes to drip
2. Verify all students have fresh nitrile gloves on
3. Remove the build platform from the printer
4. Hold the platform over a drip tray to catch excess resin
5. Using the scraper at a shallow angle, carefully remove the print from the platform
6. Place the print in the IPA wash bath (3-minute initial wash)
7. Clean the build platform with IPA and paper towels
8. Replace the platform in the printer
9. Cover the resin vat with the protective lid
10. Remove and dispose of gloves using proper doffing technique
11. Wash hands with soap and water

Discussion Points

• What did you learn from monitoring the print that you could not have predicted from the slicer preview?
• Were there any moments where you considered canceling the print? What informed your decision?
• How would you change your approach for a larger, longer print?
• What would you do differently if you were printing unattended?

Expected Outcomes

• Students should successfully complete a resin print with proper PPE throughout
• All checklist items should be documented
• Students should correctly perform the early-layer inspection pause
• Part removal should be accomplished without resin skin contact

Assessment Rubric

Criterion	Excellent (5)	Proficient (3)	Needs Improvement (1)
PPE Compliance	Correct PPE worn throughout, proper donning/doffing, no contamination transfer	PPE worn but minor protocol deviations	PPE omitted or incorrect, contamination events
Pre-Print Inspection	All checklist items inspected and documented	Most items checked, some documentation gaps	Significant items missed
Print Monitoring	All checkpoints performed on time with documented observations	Most checkpoints performed	Checkpoints missed or not documented
Print Removal	Clean removal with proper technique, no resin contact with skin	Removal successful with minor technique issues	Resin contact with skin or improper technique

Safety Considerations

• Instructor must be present and supervising throughout this activity
• Nitrile gloves mandatory for ALL resin contact — no exceptions
• UV-blocking safety glasses must be worn whenever the printer lid is open
• If any student experiences skin irritation or allergic symptoms, stop immediately and follow emergency protocol
• IPA wash station must be away from the printer (>1 meter separation)
• Dispose of all contaminated materials per the waste disposal protocol

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Last Updated: 2026-03-19