The Basics
What is a 3D printer?
A 3D printer is a machine that deposits layers of material on top of each other to produce a 3D (Physical) object, this is known as additive manufacturing.
3D printers are broken into 3 main types
SLA (Stereo Lithography)
Uses UV light to draw the part using a photo curable resin and builds layer on layer (Just starting to be used in consumer grade printers but still at the bleeding edge)
SLS (Selective Laser Sintering)
Used only in large commercial printers. Can print powdered materials such as ceramics, titanium, aluminum, alloys, nylon and many others. When the powerful laser hits the powder it becomes fused and it builds the part layer by layer.
FDM (Fused Deposition Modeling)
This is the technology that most personal 3D printers are using. This technology has matured massively over the last few years and is now at a point where it is becoming reliable enough for mainstream consumption. The process works by melting plastic filament and pushing it out of a tiny nozzle. It builds up plastic layer by layer to form the part. For the purpose of this article I will assume this is the type of printer you are using as it is the most common.
How do I make a part?
To make a part you will need to learn a 3D modeling program. This is perhaps the biggest barrier to entry as you will need to invest some time in learning. This is also the one thing you will want to get right from the beginning.
There are several types of modeling programs available but for 3D printing we are interested in what is known as solid modeling programs. This means that the objects that the software produce do not have any internal geometry.
Some of the best options for 3D printing hobbyist and general design are:
123D
http://www.123dapp.com/ - a range of Autodesk products that are aimed at the maker community.
Highly recommended
Tinkercad
https://tinkercad.com/ - A very popular and easy to use 3D modeling tool (now a part of Autodesk 123D)
Alibre
http://www.alibre.com/ - A Great option for the semi-pro
Professional options
(Only consider if you plan on producing a commercial products or want something you are not going to outgrow and have allot of spare money)
Solidworks
http://www.solidworks.com/
My weapon of choice and the most widely used software in the industry for product design
Autodesk Inventor
http://www.autodesk.com.au/products/autodesk-inventor-family/overview
Popular and takes less time to learn than Solidworks.
A note on Sketchup
While this is a popular program for beginners it is not good for 3D printing as it is not a proper solid molder. The STL files it produces normally will not print without work and running them through mesh repair programs. I do know of people who have use this but it is just not worth the extra effort. To be avoided.
Tools you need
When you are designing a part it normally has to fit together with something which means you need to be able to measure accurately.
Vernier calipers – Must have item.
(All you need is the $30 Bunnings ones unless you plan to use them every day)
Metal Ruler –Get two, a small and a large one
Radius Gauge – Hard to find but very hand for measuring the curves of corners. Get a cheap set from eBay.
Mechanical pencil – Used for sketching your ideas before you model them.
Printing the Part
Online Services
For one off prints you can use an online service, two of the biggest are
http://www.shapeways.com/
https://www.ponoko.com/
You can also sell your designs using this system.
The big downside is these services cost an absolute fortune if you need to do a few prints to get it right (which is normally the case)
Hacker Spaces
This is another great option, have a look around for your local hacker space. They have 3D printers and other cool tools like CNC and laser cutters!
You are also welcome to send me the file and I can print it for you.
Buying a printer
Which 3D printer should I buy?
I personally would get an Up Mini or an UP!+ but that is just me...
Proven technology, very reliable, It is what most members of my hacker space are using.
View attachment 37077
What about DIY printers?
Buy one. The DIY ones are great and I admire everything about them (in particular the ideals of the Rep Rap project) But you need to ask yourself if your hobby is 3D printing parts or making 3D printers work.
Designing and printing parts for saltwater use
This is what I have learned through trial and error over 1.5 years.
The best reef safe plastic you should print with is natural white ABS.
PLA will break down in water over time. Do not try it because it will not last more than 6 months.
Why white ABS?
Because the pigments added to some filament is extremely toxic to your tank.
For example a green Chinese ABS filament I tested resulted in 20 dead bristle worms and two snails (eg every living thing in the test tank at that time) White ABS is the only color that does not have pigment added to it. I have tested some other ABS colors and they were ok but for the beginner stick with white ABS and play it safe.
Keep walls over .8mm thick with 100% infill to keep things watertight. The thicker the better.
Wash and soak the parts before use, most ABS printers produce fine plastic particles which will upset everything in your tank. I normally soak the parts in water for a few weeks before use to wash away any fine particles and let any water soluble nasty’s leach out.
Techniques for small parts that need to last in saltwater.
The saltwater environment encourages small 3D printed parts to de-laminate over time, to strengthen a part for long term aquarium use it can be quickly dipped into acetone and immediately put under running water. This melts the layers of the print together and strengthens the part.
Another method that is good for small delicate parts is using acetone vapor, put the part in a tank and suspend it above the acetone. The vapor will melt the surface of the print causing a nice shiny finish and increased strength.
My 3D Printing Background:
Over the last 1.5 years I have been 3D printing almost every week. A product that I manufacture and sell online uses 3D printed parts. I help with the upkeep and running of two 3D printers at my local hacker space and have a 3D printer at home that I use for production runs.