Bread Slicer Replacement Blades: When a Dull Blade Needs Replacing, Sharpening and Spare Parts

Symptom: the slicer tears instead of cutting

A healthy hand-crank slicer separates each slice with a few turns of the crank. When the blade wears, the signs build up slowly: the slice tears at the bottom, the crumb gets crushed against the crust, crumbs pile up on the board, and the crank needs more force. A hand-crank slicer has no motor, so you feel that extra force directly in the crank.

Rule out the other causes first

1. Warm bread. A loaf that has not cooled through tears with any blade. Repeat with a fully cooled loaf – see how long to wait before cutting sourdough.
2. Loose blade. The Zassenhaus manual asks you to check before each use that the knife is correctly fastened. A loose screw lets the blade wobble.
3. Crumbs and residue. Dried residue in the teeth makes any blade cut worse. Zassenhaus suggests a cleaning brush and a slightly damp cloth; Graef says to unscrew the blade occasionally and clean the interior.
4. Technique. Pushing the loaf too fast crushes soft crumb. The Zassenhaus manual suggests turning the crank quickly and pushing slowly; the full method is in how to slice sourdough.

If a cooled loaf still tears with a clean, tight blade, the blade is dull.

Replace, don't sharpen

The makers we checked describe replacement, not sharpening. The Zassenhaus Classic manual says the circular knife may become dull after prolonged use, depending on how often it is used, and should then be replaced. Graef's manual for its manual slicers says defective components must be replaced solely with genuine spare parts, and that repairs belong with a specialist or Graef's customer service. We found no manufacturer instructions for sharpening a serrated rotary blade.

Which spare blades the makers list

ritterwerk also lists carriage, end-piece holder, rubber foot, blade cap and screw as parts for the manus 3. Neither the Zassenhaus parts shop nor ritterwerk states shipping to the US, so ask the shop before ordering. More on the brand's range is on the Zassenhaus bread slicers page, and on Graef's slicer on the Graef H9 page.

How to swap the blade (Zassenhaus Classic)

The Classic manual describes the swap in four moves. Treat the old and the new blade as sharp throughout.

1. Loosen the screw

   Use a crosshead screwdriver to loosen the blade screw and remove the washer.

2. Remove the old blade

   Take the circular knife off carefully, holding it away from the edge.

3. Insert the new blade

   Fit the new knife so that both gear wheels mesh.

4. Refit washer and screw

   Put the washer back correctly and secure the knife with the screw. Check that it sits firmly before the first slice.

On the Graef H9, the manual describes taking the blade off for cleaning: remove the carriage, turn the blade, for example with a coin, wipe it with a moist and then a dry cloth, grease the gear and tighten the blade firmly again.

Budget slicers: check the fit

For no-name crank slicers, a spare blade is the weak point. The 6.6-inch replacement blade for the Vanerepok slicer^* is sold for that one slicer, per its listing. Other budget listings name similar sizes – the CAWIU crank slicer with cover lists a 6.6-inch stainless blade – but the diameter is only one of several dimensions. Bore, gear and fastening must match too, and none of these listings states them. Ask the seller of your slicer before ordering a blade made for another one.

When a new slicer makes more sense

If your slicer's seller offers no spare blade and no fit is confirmed, a new blade can cost a large part of a new budget slicer. In that case, replacing the whole slicer with one whose spare parts are documented is the cleaner fix. Our hand-crank bread slicer guide shows which models list replacement blades; all models side by side are in our comparison of manual bread slicers.