3D Printing at the AA Digital Prototyping Lab Procedure The 3D printers at the AA are operated by the Digital Prototyping Lab staff. AA Students can submit 3D models for production in one of the machines at the lab between 10.00 am and 1.00 pm, monday to friday. After delivering the file and material or paying for high-density foam which is supplied by the DPL, your model is placed in the queue. At this time the lab staff can give you an estimation of the date and time your model will be finished, please be aware that there usually is a waiting time between 1 and 8 working days (in busy periods). Sizes and Materials The maximum build size of the 3D printer is 203x254x203 mm (8x10x8 inches). The minimum thickness is dependent on the geometry, between 1.5 and 3 mm.* The 3D printers at the AA can use only one type of material, which is similar to plaster (gipsum based). To improve the strength, models can be infiltrated after printing with either wax (paraffin) or cyanoacrylate (superglue). Using cyanoacrylate will add to the price of your model but is necessary for fragile models featuring thin and/or cantilevering parts. Waxing can be done at no extra cost. Cost of Materials The price of your model is dependent on the volume, affecting the amount of material used in the build. The amount of materials can be estimated with the ZPrint software, which can be downloaded here. - use File/3D Print Setup... to set up ZP131 as powder type; - use File/Print Time Estimator to calculate the estimated use of powder and binder; - the current pricing is 0.21 GBP per ml binder, 1.23 GBP per cubic inch powder**; - for infiltration with cyanoacrylate (superglue) add 5.00/7.50/10.00 pounds for small/medium/large models. Guidelines for File Preparation The staff at the Digital Prototyping Lab will check your digital file for errors and can give you advise on how to avoids problems or possible breaking of the model. You can check the model yourself by downloading and installing ZPrint. After installing choose the Z310 as printer type. Open your STL file and visually check for bad surfaces shown in dark grey. Use '3D View/Switch Layer View / 3D View' and press shift+A and shift+Z to scan up and down through the layers of your model to check for errors. To enable processing of your 3D model you will need to ensure the following guidelines are met: - the 3D model must be in millimeters, in 1:1 scale of the final physical model; - the model must fit within the maximum build size of the machine; - the model must be submitted in the .STL (stereolithography) format; - separate models must be submitted as separate files; (for instance 'studentname_model5_01.stl', 'studentname_model5_02.stl', etc) - the 3D model must be modeled as a singular, closed skin without any openings. Alternatively the model can consist of several intersecting solid objects, each following the first rule; - please supply 'clean' files: not other information, geometries, hidden objects/layers/ etc. Please note that 'solid objects' in your 3D model do not need to be a singular object but can consist of separate surfaces. It is advisable to join (if modeling in Rhino) as many surfaces as possible. Problems with 3D print files are commonly caused by missing surfaces, double surfaces or surfaces with the normals pointing in the wrong direction. The easiest way to check surface direction in Rhino is through changing the shading settings: - type 'AdvancedDisplay'; - open the 'Advanced Settings' and click on 'Shaded'; - at the dopdown box for 'Backface settings', choose 'Single Color for all backfaces'; - at the colour field, choose a bright colour such as red, click ok; - inspect your model in shaded mode, make sure there are no layers with the same colour as the backfaces setting; - select some or all red surfaces and use the 'Analyze Direction' tool and 'Flip' + enter to switch the normals. * The thicknesses of printed parts need to be designed in relation to the specific spanning distance fo the parts and the overall structural functioning of the model. As the 3d print material is good in compression but weak under tension, it's essential to design any single large spanning parts or cantilevers with care. Please note that it's your responsibility to make sure your model is structurally sound and minimum thicknesses are sufficient: the DPL will not reprint or refund material cost if a model is broken during normal post-processing. ** Prices are based on current cost of 3d print materials and can be changed depending on fluctuations of material prices and exchange rates.