The first post of this forum has to start with the adhesion issue: about 3 years ago, an angry customer filed a case on Ebay, alleging us for sending him a defective bottle of castable resin. This was because he tried our resin several times, and could not get anything stick to the build plate. According to him, he was apparently quite experienced: having owned 3 LCD printers and played with other brands of resins for more than 2 years! Therefore, he derived the above conclusion quite easily. If he kept getting failed prints one after the other, it must have something to do with our resin.
Sounds reasonable, right?
No, not so fast!
Conventional non-castable products are generally near transparent, thus making them have relatively long optical pathlength. Our castable resin, particularly the one for jewelry casting, however, contains some large percentage of wax, and the UV light has very limited pathlength in it. Consequently, it poses a higher requirement on the build plate eveness and surface cleaness.
For successful printing, one will need to do the following:
1) Make sure that the build plate is even and starts from a proper height. Recalibrate the buildplate, if necessary. If the build platform was not properly leveled or started from an improper height (i.e. too high from the vat FEP film), it would be difficult for layers to stick onto the build platform, and they tend to stick onto the FEP film instead. This link is a good example for build plate calibration. Similar technique can be used for other common LCD printers, such as Anycubic Photon, Longer Orange and Phrozen Shuffle, etc.
2) Roughen and clean the build platform. Too dirty or too smooth surfaces can make it difficult for the cured photopolymer to adhere to. Use a P150 sand paper to roughen the surface and use isopropyl alcohol to do a thorough cleaning afterwards. Doing this can help enhance the layer adhesion to the build plate.
3) Use proper support settings. A lot of inexperienced users typically overlooked the importance of supports for resin- based 3D printing. If the supports are too small or the density is not enough, they may fail to grow on top of the base layers, thus making it impossible to support subsequent 3D model growth. Choose either "medium" or "heavy" supports in your settings to print jewelry and dental parts.
and 4) Use the baseline parameters recommended by us:
Layer thickness: 0.05 mm
Base Layer Number: 10
Base Layer exposure time: 100 seconds
Normal layer exposure time: 18 seconds
Bottom light-off delay: 1 second
Light-off delay: 1 second.
For 0.05mm thick layer, the exposure time for the base and normal layer should be 100 and 18 seconds, respectively. The number of base layer is very important! At least 10 layers are needed, sometimes, users may even need to set it to 20 layers. A larger number of base layer can help minimize/eliminate issues caused by plate uneveness.
The good thing is that the angry customer was willing to work with us and take the above mitigation actions. In the end, he was very satisfied with our products and have became a very loyal customer for many years!