Earlier this year, we launched Black High Definition Acrylate to our community. The material was such a success, we saw amazing scale model planes, miniature figurines and cool science fiction characters. Our makers were so enthusiastic that we had to rapidly expand capacity to meet demand. Since then, we tested the material to the limits and learned how to make it better through feedback from the community. We are now ready to open B-HDA up for shop owners to make this material available to their customers.
While we expand this material offering, we also wanted to share some changes to our design guidelines based on what we have learned is possible and what is more difficult to print consistently. Updating the design guidelines was important in order to provide more reliable and higher quality prints to shop owner’s customers.
For B-HDA, the design guidelines are driven by the printing process. B-HDA uses Direct Light Projection technology where light is projected through a liquid resin which solidifies each layer of a design on a build platform. As the platform moves up, the next layer is cured by the projected light. To secure your model to the build platform and support overhangs, intertwined toothpick-sized scaffolds are printed to reinforce your structure. Since the support structures are the same as the material of the model, they are carefully removed by cutting and can make certain thin walls/wires or complex geometries more difficult to process.
We found that unsupported wires should be a minimum of 0.7 mm thick and supported wires should be a minimum of 0.8 mm thick for wires less than 35 mm in length. This is determined by our ability to successfully break away support material and clean your model. Wires that are too thin will break during post processing. As wires get longer, they typically need to be thicker in order to maintain their strength. We recommend making your wires 0.1 mm thicker for every additional 20 mm in length over 35 mm to ensure we can post process it without breakage.
We added similar guidelines for wall thickness. Walls under 5 mm in length should be a minimum of 0.5 mm thick. For every additional 20 mm in length over 5 mm, we recommend making supported walls 0.2 mm thicker and unsupported walls 0.25 mm thicker. The minimum wall thickness is determined by our ability to successfully remove support material without breaking your model and prevent the model from warping.
Finally for hollow models we added a requirement of at least 2 escape holes with a minimum diameter of 6 mm each per interior cavity. Escape holes are important for us to be able to clean the inside of the model and remove any uncured resin.
Black High Definition Acrylate has been a smash hit material for scale models and prototypes because of its high detail and smooth surface. It looks great right out of the printer, but also takes well to painting and post-processing. It’s flexible and durable. We have seen some incredible products in our factories and can’t wait to see what shop owners are going to make available for sale.
If you have questions or comments about BHDA please join the discussion in our BHDA Shopper material thread here. Do you have a product you are offering for sale here? Share your photos and products in our feature this forum here.