Sandcastle Rule: If this structure was made of wet sand, would it break?
There's a part in the production process for stainless steel 3D printing during which the model is fragile and brittle. It's basically like wet sand. When you design, ask yourself this question: if I made this out of wet sand or brittle clay, could I lift the design without it breaking? If the answer is "no," then your design might break in production.
Stainless Steel varies in color
During the production process, the steel gets infused with bronze to give the material strength. Parts closer to the bronze pool will absorb more bronze. This means depending on where your part is placed, it may absorb more or less bronze than other parts. Because our bronze infusion process cannot guarantee even infusion, you might get Stainless Steel products with slight variances in the color.
Walls under 3mm might be printable depending on your design’s structure
In general, if your model is well supported (thicker walls weave in with thinner walls), or your thin walls are small relative to your structure (small rings and cufflinks), then you could print down to 1.5mm thin walls. To learn more about this, take a look at the next few design tips.
Weave in thicker walls to support thinner walls
In certain structures, thin walls of 1.5-3mm are printable as long as there isn’t a long stretch of thin wall. If there is a long stretch of thin wall (i.e., a big, thin, flat area), then it will break. In this ring, the thin walls can be around 1.5mm thin given the high density of thick walls (extruding checkboards) around it.
Smaller models are printable at 2mm wall
A simple ring (like a wedding ring model) can be 2mm thin since the wall extend over a relatively small area. Rings less than 2mm would likely break. A larger bracelet will be less stable at 2mm. Thinner walls for smaller models may be possible.
Add more layers to support thin walls
Thin layers are printable if they are supported by additional layers of material. This ring is printable because of the double layers of mesh structure (though mesh structure is under 3mm).
Thin wires are sometimes OK if they are well supported.
Thin wires in the 1.5-3mm range are printable if they extend only a little before encountering thicker walls for support. If there is a long bar with no support, the model will fail to print. In this image, even though the wires are thin, this model can be produced since there are no long stretches where the wires are unsupported.
Hanging structures are more likely to break
Any structure that has a hanging structure is like to break. This includes the end in an unsupported, heavy object, as pictured. Another example of something that would break is a miniature of a person holding a guitar with one frail arm held straight out. The frail arm would break.
Difficult to reach places will not be polished
The media we use to get a really good polish is roughly 13-15mm in size, and any area that is smaller than that will not get a good polish. First, engraved areas in your model will remain rough because the media we use cannot reach the crevices in these structures. Second, insides of a mesh or wire structures will also be rough because the media simply cannot reach inside.
Be careful engraving and embossing details and text
Engraved details (or holes) in the surface should be wide enough to prevent trapped media. We recommend details minimum of 0.5mm wide (size 10 Arial bold), and of 1.5mm deep. Details under these measurements might get corn cob media stuck in them. Also, you might lose part of the text detail if the size is too small. Embossed details should be thick enough to withstand the media, and so we recommend to make embossed details at least 0.8mm. Otherwise, you risk your details being worn away by the media.
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