Text and photos by Stephen "Laika" Sanford
In this how-to article we will go over the usefulness of 3D printing and how you can start to use this technology to make props such as wearables, puzzles, frames, and many other applications.
3D printing is an additive manufacturing process which uses hot plastic such as Polylactic Acid (PLA) in conjunction with a 3D printer, 3D model and slicing program to create a physical product. 3D printing can be an extremely inexpensive hobby once you have access to a 3D printer where most props will cost on average 1-2$ in materials (PLA is between $16-25 per KG spool). The only limitations on what you can make are based on size, time, and strength.
The first thing you need to 3D print is a model, there are two ways to go about this, using a website such as Thingiverse.com (which is free), or a website where you can buy 3D models. You can also use a 3D modelling program such as TinkerCAD (Free), Fusion 360 (Free for Makers) or Onshape (Free for Makers) to create original designs or modify a file found elsewhere. Once you have your file, either downloaded or generated you need to save this as a .STL file.
From here we will need to put the .STL file into a slicing program. A Slicing program is one that will turn the STL file into a readable file for your 3D printer, this is where you can choose how you want to print your product. Slicing programs I would recommend are Cura (free), Simplify3D (Paid) and Slic3r (Free). This is perhaps the most important part of the process as you need to choose if your product will need supports, what materials and temperatures you are printing at, (which many other choices affecting print quality) and orientation of printing.
Filament Materials (Always check with your 3D printer specs including max nozzle/bed temps and the temperatures labelled on the material):
PLA-Cheapest/easiest option, 180°-220°C nozzle; 0°-80°C bed
ABS- Needs an enclosure and ventilation, 210°-250°C nozzle; 80°-110°C bed
PETG- High Temperature (resists warping), 230°-270°C nozzle, 50°-60°C bed
Nylon- Lightweight/Strong, 210°-250°C nozzle, 60-80°C bed
Carbon Fiber- High Durability, Impact resistant 190°-220°C nozzle, 50°C bed
TPU- High Flexible, 210°-225°C nozzle, 20°-50°C bed
Realistically, you will be printing in PLA as it is the easiest and cheapest material to print, other materials will need humidity controlled enclosures,ventilation or other precautions to print.
Support Material-
Support material is an easily removable printable area that allows a 3D printer to print an overhang. Most 3D printers can handle upwards of a 45° overhang but anything more than that and you will need to add supports unless you want to risk your print sagging or failing altogether. In the example above: a “Y” might not need supports while a “H” or “T” will need support material. Most slicers will either automatically generate supports or you may need to enter them yourself. You may also be able to avoid supports altogether based on how you orient your print.
Infil-
This is the unused areas inside of a print, in order for a print to succeed and be solid, it will need to place material inside the object to keep the layers stable and to make the product not hollow which adds strength to the print. The more infil the stronger the print is, the longer it takes, the more material you use. For most prints 10-30% is a good amount unless you plan on printing for strength in which you can go as high as 100%.
Layer Height-
This is the amount of material placed between each layer, the lower layer height the more definition a print will have but the print will take longer, the higher layer height the quicker the print will be and the stronger the layer adhesion will be. Do not exceed the layer height of the diameter of your nozzles width and printers will have a limit to how small the layer height will be. Most printers contain a 4mm nozzle, for most prints between 2-4mm layer height will be fine and most printers will go as low as .5 mm layer height. If you need further definition I would suggest looking at SLA printing which uses resin (not included in this guide).
Orientation-
3D printing works by placing material in long rows and add layers on top of each other. The weakest point on a 3D print is along the layer lines that it prints, if you are doing a tall print consider putting it on its side or at a 45° angle for more durability. Orientation will also allow you to use less support material as a 3D print may have less overhangs and print faster on its side. Because most 3D printers move on the X and Y axis for a full layer and then move to the Z axis, I would try to keep prints on the X and Y axis (on its side) unless you need a very tall print that exceeds your bed size.
Nozzle/Bed Temperature-
This are the temperatures of the extruder and the bed that the material is placed on. Always look at the information from the manufacturer, printing too high can ruin your printer and printing too low will make no material flow through the nozzle. Bed temperatures are extremely important, having a high temperature will make the material adhere to the bed better but if its too high could make the rest of the print sag. Low temperatures may make the layers not adhere and ruin the print.
After you have your slicer configured you can generate the file that is used in the 3D printer known as a .Gcode file. This can get transferred to the 3D printer via Micro SD card/ USB port/ or Octopi ( Open source wireless raspberry pi program). \
Raft, Skirt, or Brim-
The first layer of a print is the most important part of a print, layer adhesion must be perfect or the print will lose quality, peel up on the sides, or even fail. You may want to add a raft, skirt or brim to your print, these are helpful in 2 ways, first it allows you to purge your nozzle clean before starting the print.
Skirt- Prints a loose outline around the print (good for purging the nozzle)
Brim- Prints several close outlines around the print, will help with layer adhesion (may need some work to remove excess filament
Raft- Prints several layers of close outlines that are solid, this will often ensure good layer adhesion but will require some work to remove the raft after the print.
3D printers-
These come in a range of prices and sizes, I would recommend checking out your local makerspace before committing to buying a 3D printer, I also have a shop in lowell if people contact me I can give them a tour and show you how to 3D print. If you do end up buying a 3D printer a few things to keep in mind is printing area. For the most part unless you are shelling out over $500 most bed sizes are roughly 250mm^3 or smaller. Look at the recommended types of filament it can print and look up guides outside of this one for specific recommendations.
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| CR-10 4S (400m^3 build size) |
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| Prusa i3 mk3 |
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| Cossel Delta printer (circular bed) |
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| Anycubic Photon SLA (resin) 3d printer |
Now that you have all the basic info to start 3D printing, turn on your 3D printer, heat up your bed and nozzle,level the bed as needed, load the filament, load your gcode file and hit print. I would suggest sitting through the first few layers of your print and start with a small print I would suggest a “Benchy” https://www.thingiverse.com/thing:763622 or a “Calibration cube” https://www.thingiverse.com/thing:1278865 these prints will allow you to look at your print and see if there are issues with your 3D printer or your slicing configurations.
After your print is complete depending on how well the print came out, how detailed it is, or if you want to change the colors you may need to remove supports, sand, prime, and paint the 3D print. I would highly suggest if you want your print to look really smooth and nice use XTC-3D it is a resin coating that fills in layer lines that would be visible and speeds up the process of sanding and priming.
Once you get the hang of 3D printing check out some modelling software such as TinkerCAD and start making your own designs and bring them into our game.
There are many other aspects, terminology and techniques to 3D printing but this is only an introductory guide. As thanks for reading this far, here’s what a completely failed print looks like that a friend left running overnight.
