3D Printing - Things to be aware of!

Costing:

• 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.

Technical:

• 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 Cloud9 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.

Being green:

• 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.