3D-printing: an amazing yet very comprehensible, accessible, game-changing technology:
- already being used by the creative community
- limitless potential to take your virtual model, with elaborate topology and great physical complexity, and turn it into a physical object.
3D-printing: best of both worlds ~ the freedom to work digitally, and get tangible objects to hold.
- ‘bacon slice’ your virtual model
- send these digital cross-sections to machines which reproduce each unique slice
- one layer on top of the one before
- gradually adding more material in layers to the top.
Individual parts can be captured like the classic ‘ball-in-a-cage’ or designed to be interconneted yet free to move. Currently there are several different types of 3D-printing (additive manufacturing):
- Each technology is different from the next (one such process resembles a traditional ‘printer’)
- Virtual models can be 3D printed in a growing number of materials. Most accessable process extrudes material through a nozzle to build the layers. Most common is plastics but even chocolate can be printed in this way!
- metals and plastics, wax and nylon, glass and ceramics, paper, edibles and bio-materials!
- The oldest process uses a liquid (photo-sensitve) resin which is hardened by laser, layer by layer
- Others use powdered material that is ‘glued’ or fused together by laser, layer upon layer
- Another process uses paper or plastic sheets cut into exact profiles and glued to the previous profile, layer upon… I think you get the point!
- The ultimate additive method? building objects up with grains of material, tiny building blocks, with each grain deposited accurately by nimble robotic fingers
Available for both industrial and desktop manufacture, the ‘consumer 3D printer’ movement encourages more people to engage with it:
- now more affordable: you can even build your own 3D printer at home!
- easier to access via online facilities with more compatible 3D file formats available:most of the technical stuff such as repairing ‘non-manifold mesh’ and adding supports to any overhanging parts are done by the provider as part of their service
- Companies like i.materialise, Shapeways, Ponoko and Sculpteo make direct access as easy and as smooth as possible
Whichever process, material and service you choose, the 3D-printing job starts with a 3D digital model… and this is where we come in!
For 3D-printing a water-tight 3D virtual model is essential for the ‘bacon slicing’ process. The virtual model must be a complete model with all surfaces (made up of triangular planes that wrap the surface of the object) unbroken. Some 3D ‘graphics-type’ packages are prone to problems of missing or reversed surface triangles as they are not specifically designed to create solid robust models for 3D-printing. There are free applications such as Netfabb and Magics to download that check your model but do not repair it. Anarkik3D Design uses solid objects (primitives – sphere, cube, cone, torus, cylinder and a line!) from which to model, deform, construct. Problems only occur if a surface is pulled back through itself or an inner surface is pulled through the outer surface of its shell to create a topologically incorrect model. So easy in the virtual, so hard with real materials! Anarkik3D Design uses .stl which is a common file format widely used for exporting to 3D-printing. As it is available in most 3D computer-aided design (CAD) software packages it can also be used to exchange files of models i.e. useful between Anarkik3D Design and Rhino for example, but be aware that it is not a universal Industry Standard file format and problems, though rare, can arise.
Most users of Anarkik3D Design will make use of 3D print service companies like i.materialise, Shapeways, Sculpteo and Ponoko, who are making direct access as easy and as smooth as possible. You open an account (under no obligation whatsoever), upload your model to their websites, and then, depending on which company is being used, the order for selecting parameters and what they offer is different. With Shapeways you select the unit of measurement (for Anarkik3D Design this is usually millimeters) on the upload page, in Sculpteo you can re-scale your model if the price is too high, in i.materialise and Shapeways you can compare material and the cost of each. If you are happy with the price (is there a minimum order, is VAT and shipping included or extra?) and you order your 3D print you will receive it in 10 to 14 days. This will depend on material wanted – titanium certainly will take longer than polyamide!
Or you can go to a bureau if you need more support to work through the complexities of best material and system for successfully making your model, especially if there will be another stage such as mold making and casting. These are more expensive but you are well supported to get a successful model first time. Kits and low cost 3D printers are a huge growth sector as the instructions are open source and anyone can set up a group or company to make and replicate them. This viral DIY base is the principle behind RepRap and Fab@Home. There are major challenges still to be overcome. For example your model might include unprintable overhangs and if your 3D printer does not include a means of printing support structures you need to know how much of an overhang angle it can handle and whether your model exceeds that angle. With many many groups working to improve the quality and usability this is happening fast. So you too can build or buy one to sit beside your laptop and print off your models.
|Wedding engagement set designed by Ann Marie Shillito. 3D printed titanium. Diamond set in gold by hand.|
Why? (why not!)
3D-printing is such an exciting technology with so much potential, not only for prototyping but now also for creating finished usable pieces of work directly off the printer. As the range of materials has expanded, resolution improved and prices drop so the technology is finding uses in different sectors from dentistry and body parts, to jewellery and fashion, to prototyping at all stages for design, for animation models and characters, to ‘collectibles’ and customised accessories and useful hardware widgets.
3D-printing is becoming a viable business proposition for individuals and small companies whether specialising into model creation and running bureaux. With the combination of 3D modelling software becoming easier to use (there are apps for mobiles and web based programmes for anyone to easily manipulate and customise designed 3D models) and greater competition in the 3D-printing to attract your business this is a pretty good time to get modelling and not only test the market for your products and designs but sell them directly, hot off the printer.
Anarkik3D’s CEO is an long time enthusiast and had her first model printed in ABS plastic in 1998. This bangle was painted and had gold leaf applied and it is still very wearable. She also used Anarkik3D Design to designed the wedding ring for one of her daughters in 2011. This was then 3D printed in titanium. Jewellery is so suitable for 3D-printing as it fit easily into the 3D printer’s build envelope and being smallish the cost is justifiable.
Farah Bandookwala’s entire Master’s Degree work was 3D printed in nylon and steel and finished with magnets, dye and findings for earrings and necklaces. Her interactive sculptures for the Jerwood Makers Open 2011 Award were all 3D printed too.
More materials are being introduced as standard with development happening a both high and low ends. For jewellers, the introduction of gold as a 3D printable marterial will cut out the need for investment molds and ‘loss wax’ casting for production of small runs and one offs. Clay is being extruded to create ceramic work that can be fired and glass grains sintered together into vessels and artwork. 3D printers for edible materials, such as chocolate, are developing fast and will foster as many new businesses as there are applications. So don’t get left behind!
Simply type in 3D-printing in an internet search and you will get nearly 10 million responses. To get you started, here are some links to the companies we know and trust.
The range of materials that can now be 3D printed include ABS, polypropylene, clear acrylic in the plastics category, metals -steel, including stainless, titanium, sliver and gold, composites – ceramic and glass, plus rubber, paper, sugar, vegetable starch, wax, sand, foods, chocolate, human tissue….
Some materials are designed for a specific purpose such as a clean burn-out for the ‘lost-wax’ casting process, for dissolvable support material, transparency, biodegradability, flexibility, toughness, low cost, fine definition, whiteness, and some qualities essential for specific sectors: hyper-allergenic titanium for dentistry and prosthetics.
Print resolution can be varied from fine to course and can depend on sheet thickness and grain size. These also determine how fine and how strong the parts can be, cost and print time. If you want a colour there is a limited selection but if you want different bits of your model in different colours you currently only have one material option. And if you want multiple materials in the same print this is now possible. Methods for layering and bonding are tied into the materials being 3D printed and as the original patents run out the range will grow and choice widen. Selecting which one to use is set to get more complex.
The term 3D-printing only came into common use recently and to be accurate and pernickety should only be applied to one of the processes described below. The accepted term in Industry is additive manufacture which covers all the processes below and distinguishes this method from subtractive manufacture (milling and turning). The earlier and now overall term for both is rapid prototyping.
Stereolithography (SLA) is the oldest 3D printing system and developed by Chuck W. Hull (co-founder of 3D Systems) in 1986. SLA uses a vat of liquid photo-sensitive “resin” and exposure to the UV laser light solidifies a profile in the ‘x,y, axes in the thin layer of resin flooding a platform which moves down in fine incremental units in the ‘z’ axis. Parts created this way are very accurate, require minimal post processing and are ideal for use as master patterns for vacuum casting.
PolyJet inkjet technology also works by using photo sensitive materials. These are deposited in the slice profile and immediately set and bonded to previous layers by exposure to UV light. It was developed by Objet Geometries in early 2000.
The ‘extrusion’ process (FDM – Fused Deposition Modelling) uses filaments of a material such as wax or Polycarbonate and ABS plastic blend which is deposited as a molten stream through a nozzle onto a base. The nozzle moves upwards, while also building support structures for the overhanging parts of the model. The support material is either dissolvable or easy to break off. This system is used to create functional parts of any geometry and was developed by S. Scott Crump (Stratasys co-founder) in the late 1980s and commercialized in 1990. Most DIY 3D Printers use the FDM technology.
For the ‘binding’ process powdered grains are spread thinly by a roller over the floor of the “build chamber” over which a mechanical arm rapidly moves to either fuse, glue or melt one layer of grains together in the x,y slice’s profile. Another thin layer is then rolled over the top of that (the ‘z’ axis) and so on and upwards to create the model. The excess un-bonded powder is vacuumed off and the model carefully removed for further cleaning and addition of extra bonding material to stabilise the piece to make it more robust.
‘3D Printing’ uses an ‘inkjet printing’ process to deposit a liquid binder and is a reasonably accurate term to describe this system which was developed at the Massachusetts Institute of Technology (MIT) in the late 1980s and licensed by several companies including ZCorporation. With this system full colour, multi-colour robust objects can be created.v Another ‘Wax Printing’ process is similar, with wax jetted into a profile in layers to build objects which can then be used for investment casting by coating the wax with investment plaster, burning out the wax and casting in metal.
The ‘deposition’ process is closer to an inkjet printer technique as a print head moves across the build chamber depositing the material in each of the model’s x,y profile slices. It is the build chamber’s floor that lowers incrementally to create the subsequent z axis layers to build up the object.
The ‘profiling’ process uses sheets of paper, plastic inserted one at a time into the build chamber to be cut and bonded to the previous layer to build the object which is broken out of the unbonded or sliced waste material. As paper printers produce the least expensive models they are used to prototype large forms.
The ‘sintering’ process (SLS – selective Laser sintering) has the greater range of materials as many can be granulated and laser sintered together to also fuse to the previous layer. This process which uses high powder laser was developed and patented by Dr. Carl Deckard at the University of Texas in the mid-1980s, The most common and useful material used is nylon powder and apparently adding ground glasss gives even greater strength for performance and durability. Other materials include ceramic, glass powder and metals (direct metal laser sintering) including steel, titanium, silver and gold,. These developments are very exciting for designer makers but as yet hard to justify price-wise.
The process of ‘Electron Beam Melting’ (EBM) melts metal powder in a high vacuum and is distinguished from metal sintering techniques, by producing parts that are extremely strong because they are fully dense and free of any voids. It was developed by Arcam AB.
Kits and low cost 3D printers are a huge growth sector as the instructions are open source and anyone can set up a group or company to make and replicate them. This viral DIY base is the principle behind RepRap and Fab@Home and most of these systems used the extrusion method to build the model. Although there are major challenges still to be overcome there are many sharing the work to develop and solve issues. One factor limiting the design of objects for these printers that is being sorted is the mechanism to also build structures to support the overhanging parts of the model. If the 3D printer does not include a means to print support structures you need to know how much of an overhang angle it can handle and whether your model exceeds that angle and is therefore unprintable. With so many groups working in opensource mode to improve the quality and usability this is happening fast. You too can build or buy one to sit beside your laptop and print off your models.
- The method of costing of 3D printed models is BY VOLUME of material used and not by the complexity of the model. So a model that is hollow and holey is less expensive than a plain solid straightforward cube or sphere. Even with a minor reduction in scale the price can change dramatically. For example, if a 100 cubic centimetre model is say £100, scale it down by 25% and the model will be approximately 60% cheaper to make! (info from 3DPrintUK). In Sculpteo there is a slider bar for sizing which shows dynamically this dramatic shift in pricing.
- The .stl format, which basically ‘triangulates’ the model’s surface, holds this information which is required for ‘bacon slicing,’ plus other information such as colour . This facility will be added to Anarkik3D Design in the next round of development.
- Check the size of your model before uploading it. The scale of the virtual environment you are working in can be very deceptive. It could be monstrously huge or absolutely miniscule. Also different printers have different maximum sizes.
- For articulated parts the use of ‘white plastic’ material is recommended with a gap of 0.5 mm for it to work correctly.
- The minimum thickness of your model’s parts will depend on the strength required and on the material you use. For example, with coloured material, the minimum wall thickness is 3 mm but in standard white plastic, a wall thickness of 0.8 mm is both reasonably strong and slightly flexible and at 2 mm plus parts are really strong. Also the level of detail will vary depending on resolution and the material used.
- The process is additive so there is very little wastage (just support material in some processes). This is unlike subtractive processes such as milling, where the excess material is removed from the block to produce the part. The swarf and chippings of some materials are recyclable but the process of reclaiming might not be energy efficient.
- As parts are generally produced to order there is no stock sitting on shelves or unwanted work going to waste and with companies such as Ponoko signing up affiliates world-wide there is a 3D printer near you to cut down on shipping.
- One innovation is a processor that recycles chopped up plastic milk bottles decanted into its hopper and extruding it as the plastic filament used by many of the low cost and DIY printers.
1. How do I know which system and material is best for my model?
Each system has strengths and weaknesses and service companies and good bureaux are in the business to help guide you to the best technology for the job. If budget is of no concern, resin is ideal for almost any prototype, mainly because it’s more durable than powder and metal printing is probably better if mechanical parts are involved.
If your model is complex prototype it by using both the least expensive system and scale your model down a bit to reduce costs. Companies such as i.materialise and Shapeways will give you some feedback but for more comprehensive support on a ‘one to one model’ basis work with a bureau. This might turn out less expensive than the online service companies in the longer run.
2. How much will my model cost to 3D print?
The method of costing of 3D printed models is BY VOLUME of material used and not by the complexity of the model. So a model that is hollow and holey is less expensive than a plain solid straightforward cube or sphere. If it is hollow make sure it is holey to drain out the uncured resin or powder, and that wall thickness is above the minimum for the system/material being used.
Even a minor reduction in scale can change the price dramatically. For example, if a 100 cubic centimetre model is say £100, scale it down by 25% and the model will be approximately 60% cheaper to make! (info. from 3DPrintUK). In Sculpteo there is a slider bar for sizing which shows dynamically this dramatic shift in pricing.
Cost varies between companies for the same or nearly the same type of material because they each have their own pricing structures, support and running costs. They use different systems and offerings. It’s easy to shop around as you can set up accounts on the 3D print providers’ websites and upload your model with no obligation to order.
3. How can I finish my 3D printed pieces?
If printed in multi colours the company will have impregnated the bonded powder with extra fixative and no further finishing in necessary unless you want to varnish it to be glossy. Go to the 3D printing company’s forum to find the best varnish compatible with the printed material.
Nylon can be dyed and plastics painted and or sealed with acrylic paint.
Some finishing processes such as tumbling material parts including metal are offered by Shapeways etc as well as bureaux.
4. Why can’t I upload my design to a 3D printing website direct from Anarkik3D Design?
This is on Anarkik3D’s list of function to add to Anarkik3D Design to make the process even more straightforward. The list is compiled from feedback from our community of Anarkik3D Design users and our IndieGoGo crowdfunding campaign was set up to enable this and other software development to be done to enhance the package.
Not quite answered your question? Click here for a comprehensive list of all FAQs covering technical & setup, courses, software and 3D printing.
PLEASE NOTE THAT WHEN USING THIRD PARTY SERVICES TO UPLOAD AND 3D PRINT, ANARKIK3D LTD HAS NO CONTROL OVER THE PROCESS OR RESPONSIBILITY FOR THE OUTCOME.
If you experience any problems whilst uploading or when you receive your 3D printed model, please contact the company directly.
Our recommended 3D printing companies: