No, you can get both from the twine box side of the knotter. You'll need a 3/4" wrench. Make sure you take note of your shims and the location when you remove them. Also make sure you follow the shimming procedure in the operators manual. NH knives are strait knives and are easy to sharpen. To barry you are out of time in one place or another. Check the knotter drive chain for kinks and tightness. If it is too loose it will cause erratic shear bolt breakage. If the pludger stop is engagng the crank arm then it is doing its job to save your needles and cradle.