A prototype is a preliminary model of something. Projects that offer physical products need to show backers documentation of a working prototype. This gallery features photos, videos, and other visual documentation that will give backers a sense of what’s been accomplished so far and what’s left to do. Though the development process can vary for each project, these are the stages we typically see:
Proof of Concept
Explorations that test ideas and functionality.
Demonstrates the functionality of the final product, but looks different.
Looks like the final product, but is not functional.
Appearance and function match the final product, but is made with different manufacturing methods.
Appearance, function, and manufacturing methods match the final product.
Are you tired of having failed prints? Confused by the inaccurate fit of printed parts? At 3DFacture, we have identified two key problems in desktop SLA 3D printers on market today:
1. There is no optical lens to ensure a uniformly sized laser spot in a large print area, resulting in an elliptical or diffused laser spot at the edges, causing a loss of printing resolution and part stability.
2. The distortion in either a DLP projected image or a laser galvanometer optical path leads to parts printed with inaccurate dimensions.
To make a higher precision, large format professional 3D printer, we have designed “Weaver”, the first desktop SLA printer to incorporate a F-theta lens.
A laser beam usually has a Gaussian intensity profile - intense in the center and reduces towards edge. Optical lenses are used to focus the beam from a few millimetres in diameter where it exits the fibre, down to a narrow waist where it intersects with the build plate. As we move away from this focal point, the beam's cross-sectional area increases, reaching twice the minimum size at a distance along the beam called the Rayleigh length (ZR in the diagram below):
The Rayleigh length is proportional to the square of the waist diameter. The smaller the waist diameter (which is desirable for producing detailed features) the shorter the Rayleigh length and the more sensitive the system will be to focusing precision. If our focusing is inaccurate and we are a Rayleigh length away from the true focal point, then our spot area will double and our energy density will fall by 50%. In Weaver's laser with a 50 micron diameter waist, the Rayleigh length is very small. This means that our optics must be able to maintain focus within this range as the laser spot moves across the build area.
Galvo Laser Positioning and Focusing
Laser SLA printers use galvanometric ('galvo') mirror systems to direct the laser beam to different locations across the build area. A pair of mirrors are positioned above the centre of the build area and these direct the beam at a range of compound angles to the required XY positions on the build plate. The beam therefore has to travel different distances before it strikes the build plate as these angles vary. The further away from the centre of the build area, the longer is the laser beam path from the galvo mirrors to the build plate. This means that the laser beam focal length has to be varied precisely with the beam angle - otherwise the laser spot size and shape vary over the build area, which is the case for all desktop SLA printers on market.
A laser spot projected by a galvo mirror system is round in the center of the printing area, but loses focus and becomes elliptical further to the sides. This cause two serious issues. First, you can never get a focused laser spot except right at the center of the area. Some printers list a 70 or 140 micron laser spot size, which might be true right at the center, but will be far-off at the edge. That's why a well-known SLA laser printer claims a 140 micron average laser spot size. Second, the non-uniform laser spot size also makes the light intensity non-uniform, leading to frequent print failures due to a lower light intensity at edges, a frustrating yet common issue for all SLA 3D printers.
High-end industry 3D printer use F-theta lens to address the focusing issue, such as metal 3D printer AM400 by Renishaw. It comprises a multi-element lens assembly that focuses an incident beam onto a flat plane. The F-theta lens has a focal length that varies with the angle at which the beam enters the lensing element. The intention is to keep WD constant across the complete range of incident beam angles:
The F-theta lens provides a focused 50 micron round spot profile at very wide angles, increasing light uniformity and enhancing the surface smoothness of printed parts. The Weaver is the first desktop SLA printer to use a F-theta lens which gives it the highest resolution of any SLA printer available today!
Weaver uses 405nm UV laser to cure photosensitive resin layer-by-layer. It has a resolution of 50 μm in the XY plane and 25 μm in the Z axis. Weaver uses a high-end linear rail and up to 10 μm Z layer thickness can be achieved if finer details are needed. It is capable of printing objects up to 15 x 15 x 19 cm. Weaver with a F-Theta lens has great printing accuracy, surface smoothness, allowing high quality large area printing.
Comparison to other 3D printers
Weaver maximizes the printing needs of professional users: prototyping, art design, jewelry casting, and dental prints. The impressive 50 micron laser spot not only makes fine details but assures 2X smoother surface finish compared to regular SLA printers.
In the medical area, Weaver can produce precise dental models that fits perfectly with patient teeth.
In jewelry printing, Weaver allows batch production of castable jewelry molds with fine details.
In engineering applications, Weaver can product large parts with impressive quality and accuracy.
Compact Design and Control Board
Weaver solved the challenging image distortion problem of F-theta lenses through the use of an auto-correction algorithm, enabling high precision, large area printing.
We have developed our own brand of resins over the past two years at a competitive price to other resins available on the market. The list of resins include general prototyping, high resolution, lost wax castable, and more!
Weaver also provides an API to support major third-party resins.
Weaver's control software supports the use of STL and SLC . Users can also use a SD card to hold files for off-line printing using touch screen control.
Weaver is a plug-and-play 3D printer than can print right out of box without any calibration.
Different from Formlabs, our resin tank has a Teflon film coated on top of the PDMS layer to prevent heat induced clouding problem. Thus, you don't need to worry about frequent change of resin tanks.
Weaver Production Timeline
Risks and challenges
This is our third Kickstarter launch. We have successfully delivered products in all our funded campaigns. This is a fully-tested mature product based on lessons learned from our first generation Draken 3D printer. We have ordered parts and have kicked off the process of manufacturing the first 50 units.
The complete assembled printer with F-theta lens and the starter kit. Also include 1 Fixer3D repair tool, 1 additional resin tank, 1 Liter resin, and 1 additional build platform (additional $400 value).
Be our VIP, the first group to receive Weaver over Christmas!
The complete assembled printer with F-theta lens and the starter kit. Also include 1 Fixer3D repair tool, 2 additional resin tank, 3 Liter resin, and 1 additional build platform (additional $800 value).