An open-source, pocket-sized suture trainer for medical students


Pocket Sized

Less than 3in in length and under 20g, this trainer can go with you everywhere. Gone are the days of carrying around a large training board.



Quickly practice one and two handed ties, and instrument ties on any non-porous surface.


Learn Quickly

Start with cord and quickly move on to silk ties, or prolene. For an added challenge, practice with gloves!

Build your own


Download the .stl or .step files to 3D print, or machine your own trainer. You'll need to source suction cups and string to get started.

About Me

Christopher Cutler

I'm an M4 at CMS at Rosalind Franklin University in Illinois who's passionate about Neurosurgery and innovation. I invented Knotrainer to help myself learn how to suture wherever I was without carrying around a large suture training board. Before medical school, I worked as a Neurosurgical Surgical Technician and volunteered as an EMT-B on my local SAR team. When I'm not working on research projects, I love to spend time with my wife and two kids, canyoneer and mountain bike.