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How to design for 3D printing

Hi there, another guide from yaboi Jorick. 3D printing can look really easy and straightforward or a method only for the nerdiest of designers. The reality lies somewhere in between. In this guide I’m going to show you how to make a design for 3D printing and how to edit existing designs to make them 3D printable.

  • The principles of 3D printing
  • Getting the correct sizing
  • Common mistakes

The priciples of 3D printing

1. Printers always print layer by layer

3D printers are simply said just ‘toothpaste tubes’ that move around and constantly push out ‘toothpaste’. In this case the toothpaste is actually really hot molten plastic. They build up the designs layer by layer from the bottom up. When a layer is cooled down enough it hardens up and a second layer can be printed on top.

In Love With 1mm layer height on a desktop 3D printer! : r/3Dprinting

2. Printers can only print bottom to top. They can’t go back.

The printer can’t and won’t go back to lower layers. Because of this reason an upright question mark would be impossible to print. In the image below you can see a clear example of an impossible print.

3D Printing A Question Mark Symbol, The Concept Of Rapid Prototyping.  Royalty Free Cliparts, Vectors, And Stock Illustration. Image 99516817.
This ‘amazing’ stockphoto shows two major problems. Firstly you cant’t print in mid air and secondly the left part of the curve wouldn’t actually print because it would start printing in mid air and not stay in place.

3. Always make sure your print has a strong flat base

As the saying goes “You can’t build a great building on a weak foundation”. Well, you can’t print a great model on a weak foundation too. In the case of 3D printing your foundation needs to be 100% flat and have as much surface as possible.

4. Only use supports if you need to

Luckily there’s a fix for this problem called ‘supports’. Supports are 3D printed columns made to support any ‘floating’ parts of your design. The problem with supports is that they are attached to your design so it’s a hassle to remove them because it takes a lot of time and there’s a high chance for your design to break or become less good-looking. For this reason, I’d recommend using supports as a last resort.

Tips for removing excessive supports from a delicate model? : r/3Dprinting
For some designs too many supports (or supports in general) would make it really hard to get the actual model with a high chance of it being bumpy or breaking while removing the supports.

5. Just dont

3D printing is an awesome and fun method to use and has a lot of use cases. But at the end of the day, you just get a piece of plastic. If you want a plastic box, why not just buy it from the Action. 3D printing is very versatile but also very slow so try to think out of the box on how to make your design. Maybe you can modify an existing product or use a different method like laser cutting?

6. Prints need volume

3D prints need to be made out of three-dimensional shapes. if you want to print something like a lid it needs to have a length, a width, and a thickness to be able to be printed. The program for printing needs to calculate how to fill in the shapes you made. If there’s no volume there’s also no space to fill in.

3D Plotting with Matplotlib. As a Data Scientist, visualizing your… | by  Emeka Boris | Python in Plain English