Victorinox Rambler SAK TPU Case

I carry a Victorinox Rambler every day in my pocket. It is a fantastic little tool and I use it in all kind of situations. One issue I noticed however is that the knife picks up dust from my pocket, mainly on the hinges. Also, the plastic sides tend to get scratched by other items in my pocket (especially keys). So, I came to the conclusion that having a case for the knife would be a good idea.

The thing I love most about the rambler is that it is really compact and I cannot feel it in my pocket at all. Therefore, I wanted a slim case that added as little bulk as possible. I could not really find what I was looking for on Printables/Thingiverse, so I had to make my own design. I came up with a really simple TPU case where the knife can be slid into. It is hold into the case by friction and can be pulled out with a bit of force. To make this easier, I recommend adding a small landyard (or something similar) to the knife as I did on mine in the pictures.

I used this case for around one year and it held up very well. I just printed a new one because my new printer handels TPU better and the quality of the new print is much better than the old one. At the beginning, it is a bit fiddly to push the knife into the opening of the case, but after using the case for 1-2 weeks and keeping the knife in it, the opening on the case widens a bit and it gets easier to put the knife back in.

I am happy with the design and it protects my knife very well. I still cannot feel the knife inside my pocket, even with the case on it.

I used Azurefilm TPU with a shore hardness of 85A, but more common TPU with a hardness of 98A or 95A should work as well. ***UPDATE*** TPU95A (and therefore 98A) appears to be to hard, please see the “Make” section.

Printing TPU is a bit tricky and requires the right settings, which can vary from one printer to the next. Here are my settings for reference:

• Print speed 15 mm/s (on everything except first layer, here I use 10 mm/s)
• Retraction distance 1.6 mm WITHOUT unretracht! (type in -1.6 mm/s for deretraction in Prusa Slicer)
• Retract on layer change enabled
• Retraction speed 12 mm/s
• Extrusion multiplier 1.05
• Max. volumetric speed 1.5 mm3/s
• Nozzle 235°C/Bed 50°C

You may need to try out different settings to get it working on your printer. I used a bowden setup, for a direct drive extruder you can probably increase the speed.

If you want to edit the case I attached the FreeCAD .fcstd file. You should also be able to use the case on similar sized SAKs, e.g. the Midnite Manager. Happy printing! :-)