What is the Resin Washing Time Calculator?
The Resin Wash Calculator is a post-processing tool for SLA/DLP 3D printing. It determines the optimal submersion time in Isopropyl Alcohol (IPA) to fully dissolve un-cured liquid resin from a printed model without chemically damaging or warping the fragile plastic.
How to Calculate Optimal IPA Wash Times (Formulas)
The washing time depends on the concentration of the alcohol, the viscosity of the specific resin, and whether you are using mechanical agitation (like an ultrasonic cleaner).
- Standard Wash (99% IPA): 3 to 5 minutes with heavy agitation (magnetic stirrer).
- Water-Washable Resin: 5 to 10 minutes under running tap water or in a water bath.
- Thick Engineering Resins: Often require a two-stage wash (a "dirty" pre-wash for 3 mins, followed by a "clean" bath for 3 mins).
Frequently Asked Questions
Can I leave my 3D prints in IPA overnight?
Absolutely not. Isopropyl alcohol is a harsh solvent. If a printed model is submerged for longer than 15 to 20 minutes, the plastic will begin to absorb the alcohol like a sponge. The model will drastically swell, warp, crack, and turn rubbery. Prints should be washed quickly and immediately dried with compressed air.
Why is my cured print sticky and shiny?
If a print comes out of the UV curing station feeling tacky or looking wet, the washing process failed. Liquid resin was left on the surface and partially cured under the UV light. You must thoroughly wash the print until it has a matte, dry finish before putting it in the UV curing machine.
How do I safely dispose of dirty IPA?
Liquid resin is highly toxic to marine life and must NEVER be poured down the drain. To clean dirty IPA, place the clear container in direct sunlight for a few days. The UV rays will cure the suspended resin into solid plastic sludge. Filter out the solid chunks (which can be thrown in the trash), and the remaining IPA can be reused.