We’re back with another project that’s really simple to pull off, but it can be used for plenty of various fun activities – especially if you have kids. But there are plenty of practical uses for 3D-printed stamps, too! You can make almost any stamp pattern in no time if you follow some simple rules. In this article, we’ll summarize all the detailed aspects of making the stamps from A to Z.
What does an ideal stamp look like?
First, let’s take a look at what an ideal (standard, commercially-made) stamp should look like. It should be easy to use: it leaves the ink on both hard and soft paper surfaces without excessive force. The print doesn’t get too blurry when the stamp is squeezed and it prints every single detail without being pressed it too hard. Plus, its surface should have a slightly porous structure that soaks the ink just a little. So, with all of this in mind, what would be the ideal filament? Obviously, something soft and flexible, definitely not PLA. 😊
Choosing the right 3D printer
We have good news – both MSLA and FFF 3D printers work fine. However, they have some pros and cons you might want to consider.
MSLA printers like the Original Prusa SL1S SPEED let you print very detailed parts and make a perfectly smooth, flat surface on the stamp. Usually, no postprocessing is needed. And even if you encounter such a case, it’s just a quick sanding with fine sandpaper. The downside is that the MSLA technology is more expensive, and you will need flexible resin for this project. If you don’t have any other plans with flexible resins, you will most likely end up with resin leftovers with limited use and the risk of expiration.
MSLA technology allows the making of extremely detailed stamps. This looks pretty cool, doesn’t it? The used models are Stamp Bugs by Mathieu Thiel.
The FFF technology, like the Prusa Core One or Original Prusa MKS, is cheaper, the filaments have a longer lifespan, and the entire process it’s less messy. However, FFF prints are not as beautifully detailed as MSLA prints and may require some postprocessing, such as sanding, gluing, and similar. For FFF printers, we recommend using a surface that is as smooth as possible, such as a smooth sheet, glass, etc. Our satin sheet works quite well, too, but sometimes it leaves more blank spots and results in a somewhat weathered look to the imprint. The textured sheet is not suitable for making stamps.
The FFF technology is suitable for larger but less-detailed stamps.
Please keep in mind that both smooth and satin sheets need to be covered with a thin layer of glue (regular paper glue stick), to lower the extreme adhesion of flexible filaments. However, in this particular case, it is very important to make the layer of gluestick thin and as even as possible. It might require some skill but it’s worth it as every bump or crevice would be visible on the stamp.
Oh and one more thing! Did you know that our Prusa Nextruder works perfectly with flexible filaments? It allows printing TPU, TPE, and TPEE at incredible speeds and virtually no risk of filament entanglement. If you are considering getting a 3D printer for making stamps and other flexible parts with lots of retractions, the MK4, MK4S, CORE One, and XL are the best choices!
Material choice
Print it with flexible materials. That’s it! 😊
Alright, maybe some more information might be useful, at least for FFF materials: First, the material has to be as soft as possible. We tried printing with multiple flexible filaments available on our e-shop and the best is Fiberlogy Fiberflex 40D. This material is very easy to print and yet, it’s very soft. Also, ColorFabb VarioShore TPU, which allows printing at various temperatures, works very well. At higher temperatures, this filament makes the 3D-printed object somewhat foamy and even softer. This is a very good feature as it hides perfectly the 3D-printed layer pattern and leaves a porous surface with the ability to soak the print. However, this also leads to loss of detail and leaves blurry edges. The second advice from us is to dry the filament before printing. Otherwise, you might face some stringing.
As for the MSLA materials, it’s also pretty simple. We recommend printing with Prusament resin Flex, which works just fine.
Preparing the model
A stamp is essentially a 3D-printed version of a simple image. To create one, you’ll need a solid body for stability and an embossed design on the surface. An embossing depth of just a few millimeters is enough to achieve clean and consistent prints.
This is a simple procedure that can be done in many programs. There are too many to name them all, but here are a few examples: You can use something as basic as Tinkercad, or more advanced, such as Fusion 360, or Blender.
However, you don’t even need to install any additional programs! PrusaSlicer handles embossing perfectly. You just need your image in vector format, with the .SVG extension. Then, you can simply import the image to PrusaSlicer with the SVG import tool and edit it as if it were a solid object. If you don’t have an SVG file, you can transform an image with free software online (like Adobe converter), or download the Inkscape program for free. And if you wish to add custom text, you an do it in PrusaSlicer, too!
Example of embossing a .svg in PrusaSlicer
FFF printer pro tip #1: Flexible filaments are usually very bad at printing bridges and overhangs. And supports are extremely hard, if not impossible, to remove. We have a simple workaround for this, which we introduced in our older article about the color change function. You can make some sort of pre-printed supports from another filament (PLA, for example). Then, add a pause-print function in PrusaSlicer and add these supports there mid-print. Of course, preparing such support structures may require some extra work in 3D modeling programs.
Example of inserted PLA support to a Flex print.
FFF printer pro tip #2: You can design the stamp without 90° overhangs (and bridges). It is possible to make the embossed parts chamfered. However, this is something that cannot be done in PrusaSlicer and may require at least basic 3D modeling skills.
Example of a chamfered print with little bridges and no overhangs. The black color marks the first (bottom) layer.
Slicing the model
Now for the PrusaSlicer preset. First of all, remember to mirror the stamp, especially the text, in case you haven’t done so yet.
Don’t forget to mirror the stamp!
When printing with an MSLA 3D printer (SL1S SPEED), place the model with the image facing away from the print platform and print it without supports or a pad.
When printing with an FFF 3D printer (MK4S, XL, Core One …), print the model facing with the image down to the print surface to make it as smooth and flat as possible. The flexible filament should be printed with high infill, we suggest 60% (depending on the model’s size and shape). Low infill might be visible on the stamp’s imprints.
We also tried printing it facing up, away from the sheet, and ironing function on. Sadly, this never brought us the desired results as the ironed structure was visible on the imprint.
The final touch: making the handle
Finally, here are some handles. These can be stylized in many ways, you can go wild with designs! You can basically glue the stamp to any existing design to make it work.
You can also make a smart design for various travel stamps, etc. Here’s an example of the stamp that I use for Geocaching. It contains both stamp and inkpad, is small and compact, and can be hung on a carabiner, for example.
Testing the stamps
Finally, here is a good comparison of used 3D printers, materials, and sheets. As for the sheets, the textured one is virtually unusable, while satin leaves blurry marks and some blank spots. The smooth sheet works best for FFF 3D printers as it retains sharp detail on the imprint. However, any bump, dent, or other flaw is visible – even the 3D-printed layer pattern. The SLA printers are perfect for tiny details see the bug stamps at the beginning of this article. This technology can be used for larger stamps too, with amazing precision but at large surfaces, it might leave some blank spots caused by the material’s shore hardness (as seen in the picture above). Finally, PLA (and any other hard material) is unsuitable as it leaves blank spots. Making an evenly visible imprint with a PLA stamp was pretty much impossible.
And that’s all! Hopefully, we covered every single aspect of 3D printing stamps. Did you like it? Did you learn anything new? Do you plan to print your stamps? Let us know in the comments.
Used models can be found in this collection.
Happy printing.
Somehow I knew what what to expect from the QR code, yet I scanned it anyway. Well played!
Minor editing note:
In the paragraph starting "The FFF technology, like the Prusa Core One or Original Prusa MKS, is cheaper" you missed the digit "4" in "Original Prusa MK4S".
Have you experimented with different first layer infill patterns for the Flex on Smooth sheet for both aesthetic design in the stamp imprint or to reduce the printing pattern in the stamp imprint?
Also, I've found that PETG bonds well to TPU (my specific experience is with NinjaFlex as the TPU). I've used this property to print soft jaws for vices where I print the TPU face first, and then do a layer-based filament swap (no MMU here) to PETG for the "rigid" part that connects to the vise. I would imagine this would also work well for printing the handle already attached to the TPU stamp face.