OLFA knife guide for slitting 1" strips from sanding belt

thingiverse

I couldn't find suitable 1" wide 36" sanding belts for my homemade sander, so I purchased 4" wide belts instead and created this guide to hold an OLFA break-off knife precisely 1" from the edge while cutting. To my surprise, I managed to cut six 36" belts without needing to replace the blade! However, the last belt at 40 grit caused significant damage to the blade. I found that the best results were achieved when the grit was placed on a scrap board and the cut was made from the inside of the belt. This approach allowed for smooth and even cuts. To create this tool, I utilized Fusion 360. First, I designed a simple model of the OLFA and noted its blade offset of 1mm from one edge. Then, I subtracted that measurement from my initial guide design, resulting in a nice press fit that was just tight enough. The first attempt worked flawlessly! I printed this tool on my Prusa I3 MK3 using PET with a .3mm layer height. The entire process took approximately 60 minutes to complete.