i agree with stacy. my jig experience: i tried to grind knives for years on a craftsman 4x36 free hand. none were of any good quality. then i got a KMG grinder, and built some jigs. although i was thrilled i was getting consistant angles, i noticed when trying to fix or even out somthing, it held you back and made it more difficult, or impossible. even using jigs with the screw on the back edge to adjust the angle would foul things up. if you tweak that screw, and fix your bevel, you need to hope that when you flip the knife over to do the other side, that it matches up. ( meaning how close the bevel it to the spine, and the edge thickness). even a tiny burr or misalignment can screw up the game. lets say you just finished 36 grit, and switch to 80. if there is a burr or if the knife is not in the exact same spot when you flip it on the jig, you will have a slightly different bevel, and have to do the entire blade in the newly set bevel angle. even one tiny piece of metal dust between your jig face and tang when you clamp it will change the alignment. very fustrating. after a few months of that, i still was not happy. so what the hell, why not try the bubble jig, its not expensive, and it made sense watching the instructional videos. it worked like a charm the first time i tried it. i felt like i had been saved lol. then on the second knife, i noticed when i put the blade on the workrest, and slid it up to the belt real close but not touching, i would glance over at the bubble level and noticed it was almost exactly in the middle, which meant i was learning muscle memory. after doing passes, your mind/body memorizes where it needs to be held. my blades have really improved, they take less time, and making adjustments is easy so both sides of the knife look the same. now i am at the point where i do 36 grit with the bubble jig, then remove it and do all the rest freehand. once the bevel is established, its easy to feel that it is flat against the belt. i would suggest buying one. if you are in the middle of a grind, and notice you are coming to the spine too fast versus the edge, just take the magnetic level off, loosen it slightly, adjust it and go back to it. that way knowing what angle to start with is not that important. if you get one, a few tips- the magnet is really strong. make sure there there is no dust between the magnet and the tang holder when you attach it. the arm that holds the blade should be tucked tight against your waist like when you are buffing, and lock your wrist. sorry for the long story, but i wanted to give you all my thoughts on it. good luck.
