Box straps chipping edge

Hi! I cut quite much of this packaging stuff, PP, PET, PES straps, etc. :). They dull my edges after a few hundreds of cuts (where “super” steels hold it better than “conventional” ones), but no chipping for me, so far. Sometimes I have seen box cutters blades snapped by pallet strap cutting but I chalked this up to cutting with a “wrong angle” or to a too thin blade. Another reason why I normally carry my folders or try to get a fixed blade (preferably Mora type of knife) in production floors, warehouses/loading bays.
 
Sounds like you either have too shallow an angle or you twist too much when you're slicing or both. Try raising the angle a few degrees per side and stropping it then be careful to slice straight instead of wiggling it through the strap.
 
Thetimefarm said:
Sounds like you either have too shallow an angle or you twist too much when you're slicing or both. Try raising the angle a few degrees per side and stropping it then be careful to slice straight instead of wiggling it through the strap.
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My thought as well. I worked in a warehouse for 20 years and always did my cutting with one of my personal knives instead of a company box cutter, so I've cut my share of pallet strapping, zip ties, and cardboard. Bevel angle was always one of the things that I was careful about on the knives I took to work. A shallow double bevel (sharpened on both sides of the blade) was impressive as a cutter as long as I was careful to cut straight down and not hit anything "nasty" during the cut. But it was quick to fail if I put even a moderate amount of lateral stress on the edge, like working under tight zip ties and pallet strapping, then twisting the edge into the material to be cut.

Actually, the knives I found that worked best for my warehouse cutting were Emersons with their 154CM steel and chisel grind. The blades were a bit thick and took some effort to get into certain places, but the steep bevel on the chisel grinds and even on the V-grinds was double tough and took everything I threw at it. With a bit toothier edge, the 154CM steel made a great cutting edge for the zip tie and strapping material. It was like having a mini-chain saw.

OP... you can get a very sharp edge even with steeper bevels. I'd go back to maybe 20 dps like the Sharpmaker does, make sure that you have a clean edge with no wire edge, and leave the edge slightly toothy. Use a jeweler's loupe to examine the edge and a cardboard or hard bare leather strop (like Brommeland makes) to help remove the burr from sharpening. You can strop an edge to refine it without actually polishing out the toothiness if you're careful. The edge'll end up being plenty sharp and pretty tough.
 
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