# Starship 3D

Starship 3D Documentation
Starship 3D

Release status: In Concept

 Description Starship 3D a line of opensource bi-polar 3D Printers License GPL Author User:vtleavs Contributors Based-on Polar Categories CAD Models External Link Firmware

Starship 3D is a line of bi-polar 3D Printers consisting of varying models and sizes. The only model currently in development is the Intrepid Class.

## Classes

Class Radial Axis Length Build Plate Diameter Z Height
Intrepid 6 inches 12 inches 9.75 inches

## Methods

Although still in development, there are a few improvements that this printer will be able to make over cartesian printers.

1. The bipolar printer requires many less parts, as it is designed to use only what is needed.
2. Where on a cartesian printer, the build space can only be as large as the product of the axes' lengths, since the tool on a bipolar printer must only track along a single radius to reach every point on the build plate, the diameter of the build plate can be twice the length of the radial axis. The build space of a bipolar printer, therefore, should be $Z * \pi R ^{2}$. Given two printers: a cartesian with $X = 200 mm$, $Y = 200 mm$ and $Z = 200 mm$, and a polar where, $R = 200 mm$ and $Z = 200 mm$, the build volume of the cartesian would be $8.0 m ^{3}$ and the build volume of the polar would be $25.133 m ^{3}$
3. Some point down the development line, when a true slicer has been added to the Starship 3D family, a method of infill will be introduced, arcfill. This will print infill, structure and faces in an arc pattern, which, while being most efficient for a bipolar printer, is also much stronger. The strongest shape in nature is the arc.
4. Because of the nature of circles, the farther out on the radius the tool is, the greater the arc length. For instance, knowing that the formula for arc length is $2 \pi R(\frac{\theta}{360°})$, then at $30 mm$ from the center, if the buildplate is rotated $1.8°$, the resulting arc length is $2 \pi * 30mm(\frac{1.8°}{360°})$, which equals $0.94247779607$. However, if the tool moves to $60 mm$, then a rotation of $1.8°$ would result in arc length $2 \pi * 60mm(\frac{1.8°}{360°})$, or $1.88495559215$, double the arc length at $30 mm$. Because of this, the typical step angle of an ungeared Nema 17 is insufficient, so a Nema 17 geared $27:1$ is currently being used for design purposes.

## Slicing

The current method for generating g-code for the Starship printers is to translate an existing g-code file into polar g-code (polar g-code is no different than cartesian, just easier for the interpreter to read.

To help contribute to the slicing program, head over to the Github.

## Firmware

The Starship firmware is being built in Arduino for the RAMPS 1.4 control board. The most notable difference addressed in the firmware from that of cartesian printers, is the fact that the farther the tool is from the center of the build plate, the larger each step becomes.

To help contribute to the firmware, head over to the Github.