How to Sharpen a Chisel

Chisels are essential tools when it comes to working with wood. They can be used to carve small details as well as remove huge wood sections. With a variety of sizes and uses, chisels date back to prehistoric times where sharp rocks were used for carving wood.

However, an unsharpened chisel can be dangerous so make sure to sharpen your tool often for the best results. Follow these steps to ensure your chisel stays sharp and effective.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Chisel
• Magnifying Glass
• Bench Grinder
• Light Machine Oil
• Work Gloves
• Work Gloves
• Magnifying Glasses
• Bench Grinders
• Chisels
• Fine-grit Sharpening Stones
• Safety Goggles
• Safety Goggles

1. Check the beveled edge with a magnifying glass for burrs and nicks. Grind them off with a medium grit wheel on your bench grinder.

2. 

   Hold the blade with the beveled side up and move it side-to-side against the wheel.

3. Be sure the cutting edge stays square with the wheel.

4. 

   Turn the blade over (bevel-side down) and repeat the previous step, but this time hold the chisel at a 25-degree angle to match the bevel.

5. 

   Finish the edge on a fine-grit stone. Put a few drops of light machine oil on the stone.

6. 

   Hold the bevel flat against the stone. Pull the chisel toward you and lift at the end of the stroke.

7. Wipe the bevel clean about every third stroke with a clean rag and re-oil the stone.

8. 

   Drag the chisel once across the stone with the bevel side up to remove any burrs that may have been created.

9. Re-examine the sharpened chisel with your magnifying glass.

Tips & Warnings

• Keep the blade from losing its temper by cooling it often. Dip it in a cup of water and return to sharpening.
• A dull chisel is extremely dangerous and requires more force. Make sure that your tool is sharpened.

on 11/22/2005 Use a grinding wheel only if you have a large chip in your blade! Grind it to shape and then switch to a manual wet grinding wheel or a oiled hand stone and take a good amount of material off to remove the ruined temper.

After you have a fine edge on your chisel, unless you chip it you should be able to keep it continually sharp by using some fine grit buffing compound on a cloth buffing wheel.

on 11/22/2005 You have to be really careful when grinding not to get it too hot. To grind out a chip in a chisel, grind straight across, then re-grind the bevel using a spray water bottle to cool the edge (careful with the electricity). When it is almost sharp, sharpen it with a water stone (or sandpaper on glass).

on 11/22/2005 Sharpening your chisel on a grinding wheel is quite difficult. The thinnest part of the chisel (the edge) will very easily exceed a temperature of 350 degrees C or 660 degrees F. Whatever you do after this, in terms of sharpening, will be a waste of time. Your hardened and tempered steel has now become soft and useless. This can only be remedied by grinding away all that was overheated. I admit that when some yokel has abused a chisel, I do use a grinder, even an angle grinder if a lot has to be removed, but this takes very frequent quenching and avoiding heat build-up at the edge.

Wet-grinders are tops. Once your chisel has been sharpened, you can use an Arkansas stone or something to do the last bit of proper sharpening (fine grit automotive waterproof paper on a flat surface works too). Now you strop it on leather, or a piece of cardboard. This involves lightly stroking the edge over some surface from both sides. It?s good if a chisel takes off the hair on your arm; but even better is if you can shave your cheek with it.

on 11/22/2005 Unless someone used your chisel as a pry bar, never use a grinder. You'll ruin the temper and get an awful edge. Use stones up to 1200 grit or sandpaper on plate glass (auto paint stores offer better sandpaper).