This is a common problem when sending files to a rapid prototyping bureau, errors can occur in the files depending on the software you have used to produce the STL file and how you modelled it. Common issues are:
- Reversed normal’s
- Bad edges
- Holes in the mesh
- Noise shells
All of these will prevent your model from being 3D printed. These errors can normally be fixed using software freely available on the internet, one such program is Netfabb which is an STL file viewer and repair tool. This software is free to download (Scroll to the bottom of the page, you don’t need to fill in all of the information!) and use and will identify basic errors and repair them if possible. It is available for Windows, Linux and Mac.
Once you have installed Netfabb open up the software and it should look like the image below:
The important areas on the interface are highlighted above. You can rotate the model by pressing and holding the right mouse button and then dragging; clicking on one of the standard views will reset the viewpoint. To zoom you can use the scroll wheel on your mouse or you can use the icons shown above.
The basic information area of the interface shows the overall dimensions of the part (the bounding box), the volume, the surface area and the number of triangles in your model, this information is useful when you are selecting which 3D printing technology to use.
The analyse, repair and measuring area of the interface are the functions that we will be using to fix the STL file. Selecting the analyse button will generate additional information about your part including where and what the errors are if any. The repair function will analyse and repair the errors that it finds. There are a lot of free STL viewers out there but there are very few that will repair your file as well. The measuring icon will do just that and will allow you to take measurements around your model by selecting different triangles; this is useful for checking wall thicknesses and minimum detail sizes.
The Screenshot below shows a part that has been loaded into the software. You can see from the bottom right icon that there are errors in the file as soon as it has been loaded.
Fixing your STL file
Select the part so that it turns green and the bounding box is shown, now click on the Repair icon and this will open up another interface screen in the bottom right of the screen. Click on the auto-update tick box to ensure the data is up-to-date while you are working on it.
Click on the automatic repair button, this will open a popup box which will appear in the middle of the screen.
From this box you can choose either the default repair or simple repair option. The default option will run all of the repairs that Netfabb has so I would recommend that you use this one. Click on the execute button and Netfabb will carry out the repairs. Your statistics area should now update to show that there are no more errors in the 3D model. Border edges, invalid orientation and Holes should all be Zero and shells should preferably be equal to one although it won’t if there are multiple parts in the STL file.
All that is left to do is click on ‘Apply Repair’ and then confirm that you would like to remove the old part. To save your part you need to click on ‘Part>Export Part>as STL (binary)’ and that’s your STL file fixed.
Rapid Prototyping (RP) is defined as a group of technologies used to quickly produce a scale model of a component or group of components using 3-dimensional computer aided design (CAD) data. It can also be referred to as additive manufacturing and/or 3D printing.
What this actually means is that a computer generated virtual design from 3D design software is translated into thin horizontal cross-sections. These layers are created one at a time to create a real physical model where the layers are joined together or fused automatically to create the final model. This is where the names additive manufacture and 3D printing are derived. It is a ‘what you see is what you get’ process where the virtual model is almost identical to the physical model. This gives the technology a fundamental advantage over traditional techniques as it can create almost any geometric feature or shape.
Why would you use Rapid Prototyping?
- To decrease product development time (time compression technology)
- To minimise engineering changes
- To increase effective communication between engineers, product designers and marketing departments
- To extend the product life cycle
By letting the design department, manufacturing/production engineering and marketing departments see the model at an early stage allows costly errors to be eliminated. Any mistakes can be rectified before expensive tooling has been made for full production whilst the models at this stage are relatively inexpensive.
The word Rapid is relative as some models can take only a few hours to build whereas others may take several days. The time taken to build is dependant on the size, complexity and the technique being used.
The standard file format that is used between the CAD software and the rapid prototyping machines is the STL file format. Although for colour models such as those produced on the Z Corporation machines the VRML format is used, as there is no colour information in the STL file format. Both formats create an approximation of the shape of a component or assembly by using triangular facets. The smaller the triangles the smoother the surface, however, there is a point where there will be no further improvement because of the limitations of the technology. In order to see how the rapid prototype machines will see your model you need to turn off smooth shading in the 3D CAD software.
There are a variety of methods that can be used to deposit the material and which one is best for your project will depend on what you want from your models. They are:
- Stereolithography (SLA)
- Selective Layer Sintering (SLS)
- 3D Printing (3DP)
- Fused Deposition modelling (FDM)
All of these techniques require a second material that is known as the support material, which allows tapered surfaces and overhangs to be produced as the component is ‘grown’. These come in a variety of forms that can be powder, liquid, wax or even the model material that has to be cleaned or removed from the model afterwards. Some machines generate the support structure for you so you have no control over where it goes, whereas other machines you have to manually generate the support material using specialist software.
As materials and techniques develop, increasingly Rapid Prototyping technologies are being used for production parts rather than just prototypes. Currently RP models aren’t as accurate or the material isn’t as good as CNC machined parts for instance, but, some of the most accurate 3D printers are generally creating parts to a tolerance of +/- 0.125mm. This does not mean that they cannot do better but this is what service providers generally quote. Traditional techniques such as injection molding will be cheaper for higher quantity parts but additive manufacture can be faster and less expensive for smaller batch quantities, especially for hard to manufacture parts.
Some of the other advantages to Rapid manufacture are:
- Low material waste
- Speed
- Complex Geometries
- Energy Efficiency
Rapid Manufacturng is widely regarded by experts as the next stage for Rapid Prototyping technologies.
3D printing is an ideal complement to 3D CAD design by offering a fast, low cost alternative to traditional rapid prototyping technologies for building concept and functional prototypes.
Currently 3D printing materials used to produce prototypes range from resins, polymers and plasters and there are many new ones to come in the near future. The use of your prototype will determine which 3D printing material is best for our project. Key factors that influence the choice of prototype material are lifespan, complexity of geometry and the durability of the model.
A summary of the prototyping materials that we offer here at 3D Creation Lab are shown below:
White detailed material – Acrylic based photopolymer, highly detailed, best for smaller objects, medium strength, fairly durable, low melting point (50 degrees C), superior surface finish to all other rapid prototyping technologies due to a layer size of only 0.03mm.
Durable material – ABS plastic, strong, best for larger models, low detail level, rigid, low quality surface finish, medium melting point (127 degrees C), layer size of 0.25mm
Multi-colour material – Powder based material, high resolution, rigid, brittle, low strength, surface finish has a sand effect to it, low melting point (60 degrees C), layer size 0.09 to 0.25mm
Many designers and companies use prototypes and models for the purpose of product and functionality testing of new designs they can also be used to obtain customer feedback for new products. The data collected from these tests is then used to change the prototype models and improve the product or design.
3D printed prototypes are a crucial tool for rapidly making cost efficient design modifications before a product goes to manufacturing where these changes will be extremely costly. The time and cost savings using rapid prototype models can be as much as two thirds.
3D Rapid prototyping advancements allow for faster and lower cost prototypes and model fabrication by eliminating manpower and expensive tooling which allow companies and inventors to bring there products and designs to market faster than the competition.
The question is does your company need an unfair advantage in today’s current economic climate? I am guessing the answer is yes! If so rapid prototyping technology is what you need.
3D Creation Lab is pleased to announce it can now offer the following services in addition to its 3D printing service.
2D to 3D Conversion
Don’t have a 3D CAD model? We can convert your 2D drawings or sketches into a 3D CAD model for you. From engineering widgets to houses we can convert them to 3D CAD data from napkin sketches or 2D engineering drawings.
Prices are dependent on the complexity of the component being modelled and what information you can supply us with. E-mail info@3dcreationlab.co.uk with the details of your project for more information on how we can help you.
3D Photo-realistic Rendering
We use specialist software to produce a digital image of your 3D CAD data that is as good as a real photo without ever involving a photographer or a lens cap! 3D Rendered images are now widely used by marketing departments to give their clients images that would otherwise be impossible or extremely costly to produce and in instances where no physical model of the object exists.
Using 3D visualisations on your product marketing can reduce the project timescales and communicate your design or product to your market and customers to measure reaction before you commit to building.
Prices are dependent on the scale of the project and what information you can supply us with. E-mail info@3dcreationlab.co.uk with as much information as possible and we will get back to you with a price for creating your photo-realistic rendering.
3D Creation Lab……now creates 3D in the physical and digital worlds!
Pixologic have recently launched 3D Print exporter and Decimation Master plugins for their amazing ZBrush 3D sculpting software.
Within a couple of days of this we got an enquiry from Matthew Long at the West Wales School of the Arts to 3D print his model “Flake the Dust mite” which he had sculpted using ZBrush. The STL file came to us with only a few errors which were easily fixed with our specialist software so we were able to give a quick quote for a 3″ high printout in our White Detailed material.
This was our first ZBrush 3D print so we were intrigued by the process that the designer goes through and how the detail of the model would come out from the 3D printing. Coming from an engineering background where primitives and Boolean operations are the order of the day I could only imagine being able to produce a model like this, the photo below shows the workflow for the subdivision modeling process from the initial idea sketch to the final rendering.
As for the 3D printing it was a straight forward print apart from the removal of the support material which had to be carried out by hand rather than the waterjet because of some of the features being so thin. As you can see from the photo and video below the model came out really well and to quote Matthew “Just had the model delivered, looks fantastic! Better than I imagined”. I can’t say more than that apart from I can’t wait to see what character model comes through next……
Photos & Video courtesy of West Wales School of the Arts
More information on the ZBrush plugins:
With 3DPrint Exporter you will be able to export your favorite ZTool in STL and VRML file formats, opening you to the world of 3D Printing.
Who has never dreamed about having your virtual sculpting in “real” 3D, standing on your desk? Now it’s possible for you to print your ZBrush models:
- Sculpt your art with ZBrush
- Optimize if needed your model with the Decimation Master plugin
- Export it with 3D Print Exporter
With Decimation Master you will be able to easily reduce the polygon count of your models in a very efficient way while keeping all their sculpted details. This solution is one of the fastest available and is able to optimize your high polycount models from ZBrush, allowing you to export them to your other 3D software packages.
Sculpt your model with ZBrush, add all your small details and push your artistic skills, then optimize your ZTool. Export it to your favorite 3D package which will now be able to open your sculpting to create specific textures like Normal Maps or Ambient Occlusion maps by baking the high resolution mesh information on a low resolution mesh.
Another use is to export your model for a Rapid Prototyping process (3D printing) and bring your virtual art to a real object but also displaying your model in a real-time viewer such as PDF 3D. The possibilities are infinite!
Main features
- High quality optimization with accuracy details.
- Two different optimizations for a better control of the result.
- Optimization based on the polypainting information
- Support of Masks for details protection.
- Border protections.
- Support of the symmetry and partial symmetry.
- Optimization of your UVs for exporting models for 3D Color printing
Extras
- Export all SubTool as one OBJ file
- Clone all SubTools
Objet geometries have just introduced the 350 to its Connex family of multi-material 3D printers. Like its older brother the Connex 500 it offers multiple materials in one build tray, not only different 
materials for separate parts but different materials within the same part! These are the only 3D printers on the market that can do this by using Objet’s patented Matrix Polyjet technology.
This technology allows the machine to offer very close simulation of end product. It supports FullCure and composite materials like photopolymer models and provide exceptional quality and features which are way ahead of the technology curve. The machine also provide “Digital Materials” which are composite materials made up of any two Fullcure model materials integrated in specific concentrations and structures to provide the desired mechanical properties, which you can see from the video and pictures below.
Where’s that phone number for the bank manager……..
There seems to be plenty of buzz around 3D in general at the moment, and much of it is biased towards filming and viewing 3D images or videos. All of these technologies 
require special glasses to get the affect though.
This company stands out from the crowd with a technology that they have been developing for 4 years, they can bring full colour, glasses-free holograms to life! This has the potential to bring the technology of Star Wars into the realm of reality. ZI’s software puts a virtual camera inside every point of a digital models holographic vertical plane so that it can measure its surface volume. As you can imagine the amount of data required to produce this is enormous as there are approximately a million points to analyse.
Zebra then send it to their printer which processes the data containing distinct points of view to a plastic polymer which creates a sheet full of 1mm holographic tile encryptions. Each of these tiles is an image conductor that is sensitive to light, so when light is shined its scatters around and all image angles are shown at once. This results in a free-standing 3D model appearing from the sheet as shown in the picture shown on this page; it is a very clever optical illusion. With support from DARPA, Zebra Imaging has recently developed a holographic display that is capable of producing this effect in a scalable dynamic near real-time display. The US army have already picked up the technology for displaying maps of constantly changing battlefields which can be printed on the fly.
This technology is amazing but currently costs thousands of dollars so it is a long way from being available to everybody, rapid prototyping with 3D printing on the other hand is here and affordable now!
Objet technologies have partnered up with footwear giant Adidas-Salomon AG to help move them towards a more streamlined digital process for sharing their designs between offices across the world.
Adidas-Salomon AG has a vision which it has been working on for four years, this is to have a complete digital process that will enable them to create and share 3D data back and forth between their corporate HQ in Germany and Portland in the USA as well as all of its corporate units and factories across the world. They recently took a step closer to completing this goal when they introduced the use of 3D printing by Objet.
Adidas-Salomon AG has been using rapid prototyping technologies since 1998 so this isn’t a new technology for them. The initial use for the technology was for design verification but they have realised that it can go much further than that.
The Objet Polyjet technology produces a superior surface finish to other rapid prototyping techniques (one of the reasons we use it at 3D Creation Lab 
) Vice President-Product Creation Technologies Gary Pitman explains why they also chose Objet: “Our research told us that having a higher-quality RP model would allow us to influence more than just the design verification phase; we felt we could save significant time and money by using the RP models as the master when vacuum-casting parts for development review and eventually, for production tooling.”
“Installing a machine for both headquarters has put us at a higher level. Objet’s helped change the way we work,” Pitman states. “Our designers and engineers need to hold and feel the model in their hands; it’s always important, and with Objet, it’s almost like having a 3D fax capability.”
Both companies are now searching for new ways to apply the Polyjet 3D printing technology to other areas of the business such as the accessories and gear division which produces equipment for the football sector.
All they need to do now is see what they can do about the referee’s decisions!
The advent of 3D visualisation software delivers a giant leap forward for property developers and Architects. It provides them with a “fly through” to show the client and they are hopefully suitably impressed and sign on the dotted line. But reading an article in Cadalyst magazine recently about Andrew Chary the principal architect at Andrew Chary Architects in upstate New York it becomes clear that many clients don’t fully understand what they are seeing in an on-screen walkthrough.
Chary says “The software doesn’t convey perspective, such as the relative size and location of rooms. The walkthroughs don’t excite clients, models do”, he continues “Holding a model in your hand, there’s a light bulb that goes off. It’s almost like a fourth dimension — you see things better when you hold it in your hands, turn it around and upside down. It’s a whole new perspective. People are extremely surprised to see the models” Chary said. “They light up like it’s a toy”
“Now the client is all of a sudden in control.” Chary says seeing the 3D-printed model “results in intelligent questions and an understanding of the design that is gratifying.” Builders also respond to seeing the connections in a model, Chary said. “It excites them and gives them confidence.”
So clearly there are major benefits to presenting 3D models to clients and helping the design and build process, especially in the current climate where the smallest detail can give you the edge over your competitor. Whereas this is becoming more and more common in the USA, in the UK there are only a few forward thinking companies that have started to use 3D printing as a selling point. One of these companies is property consultants Urban Aspects who have just discovered the 3D printing process and are looking forward to using it on their clients’ jobs for the first time.
Managing Director Russell Ranford says “We are always looking for a different angle that will assist our clients with land and property disposals,
so far the clients have been very impressed with the example models provided. In the current marketplace you need an edge just to survive and move forward in business. For bespoke properties 3D printing will enable us to provide scale models for clients to really appreciate what their properties will look like. This will undoubtedly prove to be a much more effective way of communicating proposals than 2D drawings. Property developers are only just starting to use 3D visualisations as a selling point which means that with 3D printing our clients will be ahead of the curve”.
Of course there is a cost issue to address as well. 3D printing is getting cheaper but it isn’t currently in reach of your average Joe on the street, but as Russell points out “for some of our clients spending £1,000 to £1,500 on 3D visualisation and a 3D printed model will be minimal when you consider the cost of building a house and the business it can potentially win.”.
Matt Latham, a 3D artist for Quay Design Creative Solutions is also keen to use the 3D printing process after a recent demonstration of its capabilities here at 3D Creation Lab. Matt uses 3D modelling software to produce the afore mentioned 3D visualisations and walkthroughs for property developers. He immediately saw the potential for the models to impress clients with and also sees it as a unique selling point, Matt says “As soon as I had the demonstration at 3D Creation Lab I was amazed that this technology even exists, I had never seen it before, except maybe on Star trek! I can see how these models could give a unique opportunity to seal deals in the property & architectural markets”.
This video is a demonstration of our Objet 3D printer and shows the level of detail that can be achieved with this type of rapid prototyping machine.
