Resins for Moai
Moai uses a 405nm 150mW laser and can work with light-sensitive resin designed for said wavelength. However, there are other factors affect print quality and success rate, and we cannot guarantee every resin for 405nm will work with Moai printer.
For optimal results and hassle-free printing, we recommend you use Peopoly resins as they are most optimized for Moai.
OVERVIEW of Moai Standard Resin:
Moai standard resin is a UV curable acrylate-based resin developed for laser SLA printer. It responds to 405nm UV light and has a follow mechanical property:
Hardness (Shore D): ASTM D2240 82 Tensile strength at break (Mpa): ASTM D638M 60 Elongation at break(%): ASTM D638M 8% Young's modulus (MPa): ASTM D638M 830
At 25C degrees, the viscosity is 600cps. Density is 1.13
The ideal printing temperature is 20 to 30C. The higher the temperature, the lower the viscosity and requires less UV energy to cure. Once cured, it can withstand temperature up to 70C before softening.
Shrinkage post cure is 6.5% and is consistent for acrylate-based resin
In the user guide, we recommend laser energy at 61 with default Cura profile. This is selected to ensure high print success rate for new users. Use can dial laser down to increase PDMS lifespan. Using the default Cura profile, the user can print using laser energy between 57-61 for Moai. 57-58 are preferred by experienced users who have been using Moai for production. However, if you find large print not sticking well at a lower energy level, it is best to increase to a higher level. We also have users reported using laser energy at 55/56 but with slower print speed in Cura. Moai is designed for experiments and customizations so find the best settings for your application.
an example of lower laser energy can be found here
Lower energy leads to lower shrinkage during printing and smaller laser spot size.
Resin Exposure Reference
Here is a list of resins that our users or we have tested on Moai.
While resins all have different chemical content, it is important to take safety precautions. Use nitrile gloves when handling resins as it offers better protection than latex-based gloves. Wearing safety goggles is highly recommended. If resin gets on skin, wash with warm water and soap. If resin gets into eyes, washing with warm water and consult a medical professional. It is best to review MSDS document for the resin before printing it for the first time. Peopoly resin MSDS can be found here
Most resin cleans well with Ethanol or IPA. Ethanol works better but is harder to come by in most countries. You can use other types of degreaser to do the job in a pinch, including warm soapy water. It is important to wear gloves when cleaning. For Ethanol, quick bath for 30-60 seconds assisted with painter brush cleaning off uncured resins. A painter brush can significantly increase cleaning efficiency but avoid using toothbrushes as they may damage the surface.
Post Curing can be done using 395nm or 405nm LED lights. You can submerge object in the water to increase efficiency. A good washing reduces a lot of curing time. It shouldn't take more than 10 minutes to cure with right cleaning and the right light source.
Moai resin is not very light-sensitive and can be kept in the vat with vat cover inside of the printer with the door closed for 2-3 weeks without issues. Make sure to mix up the resin and expose the PDMS layer of the vat to air before printing. Please keep environment temperature below 40C for storage with 20-30C being ideal storage temperature. You can find several printable Moai related add-ons, including vat cover in Moai Thingiverse group.
The Moai vat is made of high-grade acrylic that can endure ethanol and IPA cleaning. We recommend ethanol over IPA because it is less corrosive. The interior of Moai vat is lined with PDMS layer. This PDMS layer should last 15-20 prints with Moai resin if recommended exposure settings are used. User can recoat their vat with this instruction from David Wang Honey.