UPDATE: Save yourself a few steps and check this out! http://3dp.rocks/lithophane/
This month I updated the EngineerDog ‘Best of the Internet’ web tools list by removing dead links and incorporating new suggestions from awesome readers like you. (Feedback is appreciated thank you!)
As part of that process I came across a couple new sites that gave me a fun idea.
I’ve found that it is possible to use a string of free web-browser based tools to convert common image files into different file types that can be used for 2D CNC work or 3D printing. This process can be used for drawings, logos, or whatever image you might want to try it on.
To test it out I converted the EngineerDog Logo into a coaster in a single sitting. This article will walk you through the process I used step by step.
High Level Summary of Steps:
- Create PNG Image. You can use MS Paint to edit any image and save it as a PNG file.
- Change Image to high contrast outline. Convert to black and white, white to become empty space, black to be printed. Use Pixlr.com link here or Microsoft Office tools.
- Convert Contrasted PNG image to SVG. Use Convertio.com link here or alternative choice autotracer.com link here.
- Convert SVG to STL. SVG2STL.com link here.
- Resize STL & Add Backing. TinkerCAD.com link here.
- Optional: Add words of any font. MXS Text-STL.com link here.
Notes on Jargon:
- .PNG file = A very common image file. Is the most common lossless image compression format on the internet.
- .SVG file = A vector based image readable by 2D CNC software (CNC routers & lasercutters.)
- .STL file = The standard 3d printable 3d model file type.
Steps in Detail:
1. The main Enginerdog Logo was created for me by talented animation artist Jesse J Jones, so selected because I love his work.
I copied the image and pasted into a Microsoft Paint window so I could make the unsophisticated edits that I am able to. I found a public domain image of a wench from google and modified it to my liking.
Then I created the fun font using FontSpace.com to overlay ‘EngineerDog.com’ over the wrench. Again I colored it in using MS Paint.
When complete I saved the file as a .PNG to proceed with the next steps.
2. The next step is to edit the image to increase the contrast so I can see where all the edges are. The colors don’t matter for this, all that is important is their brightness/contrast relative to the rest of the image.
White’light colors will get converted to empty space and black/dark will eventually be printed solid. Those are the only two possibilities.
The tool for this is Pixlr which is like MS Paint but with more capability and browser based. It allows you to adjust the overall light vs dark by choosing “Adjustment” then “Threshold”. (See pics below) When you are finished select File>Save>PNG image.
In my logo image the dog collar was a mid-range color and ended up creating a line of contrast too thin to 3D print, so I used a paint brush tool to better define the collars perimeter.
3. The next step is to upload your PNG to a program that converts the PNG image to SVG. You can use the Convertio.com link here or alternatively autotracer.com link here. (Good to have multiple options in case something goes wrong or a link dies over time.)
In either case all you to is upload & hit convert and download the SVG file. Super easy.
If you have a laser cutter then at this point you are done because this file type can easily be used in laser cutting software to generate g-code and zap your picture on everything. If you want to 3D print it then read on.
4. The next step is also an easy one. Upload your SVG to SVG2STL.com, then select a thickness of 6mm , hit convert, then download the resulting STL file. The thickness here doesn’t matter too much because you will be able to stretch out the thickness as needed in the next program.
5. Next import the STL model into TinkerCad. STL file types are normally difficult to work with; they are kind of like the pdf of the 3d world. TinkerCad is a simple & free tool mostly intended for empowering kids but its ability to easily edit STL files makes it rare and valuable.
TinkerCAD is the equivalent of Microsoft Paint for your 3D object. Not sophistocated but you’d be surprised what you can do with it. In this demo all I did to the logo was resize it as needed.
My logo’s line thickness (or thinness in this case) turned out to be a limitation because if I scaled down the size of the logo any further then the lines would be too thin to physically 3d print! So I had to either print it big or else go back to step one and cover all the outlines with a thicker paintbrush.
My logo also has lots of floating/separate pieces so I needed a backing to hold everything together. I chose a 100mm diameter disc to create a coaster.
In TinkerCAD, to create the lip around the perimeter I created two discs, classified the big one as ‘solid’ and the smaller one as a ‘hole’, and then selected both and chose ‘group object’. Combining a ‘solid’ and a ‘hole’ cuts out the little circle from the big one. (note that the grouping process can be reversed and modified by choosing ‘ungroup’. Thingiverse’s undo function has a long memory. ) After that I selected the resulting disc and my logo, then grouped again.
Now export the STL from TinkerCAD and print away! I shared branded coaster pictured along with a blank one on Thingiverse here.
Now that you know how to make pictures printable, what will you use it for?