Chisel SharpeningHow to sharpen chisels and plane ironsTips on this page cover;Regular chisel sharpening is the easiest and best way to keep your chisels in good working condition. The longer they are left the harder it is to get a good sharp edge. Most people think sharpened chisels are dangerous but the opposite is true. Trying to force blunt chisels through timber increases the risk of slipping and either injuring yourself or damaging/ruining the workpiece.  I was first taught how to sharpen a chisel soon after I started my apprenticeship. I was shown the traditional way of how to use a double sided oil stone to sharpen my chisels and plane irons with, using a honing guide to keep the blades at the correct angle. The old, experienced carpenter that was teaching me had an oil stone so old it had been worn down to a bath like shape over the 40 odd years he had been using it. All his chisels had worn to the same curved shapes too, and so really only his curved chisels could effectively be sharpened on that stone! (oil stones can be flattened before they get that bad by putting wet and dry sandpaper on a flat surface and rubbing the stone on top). This is the problem with oil stones, they are messy and need to be flattened regularly. Diamond whetstones don't suffer from these problems. Chisel sharpening involves two different angles, one being ground the other honed. When first purchased they will likely only have the ground, bevelled edge of 25°. A honed angle of 30° will need to be applied onto the tip of that bevel to give it the sharpest possible edge.I invested what was a lot of money back then (especially for an apprentice) in a nice new diamond sharpening whetstone to achieve this. Lots of the old guys on site jumped on it and were amazed with how quickly they could get a razor sharp edge on their chisels. I had a tendency to 'roll' the chisel at first, and found it difficult to keep it held at the right angle whilst moving it backward and forward over the stone. To go with my nice new diamond sharpening stone I also bought a honing guide. A honing guide is a gauge that holds the plane iron or chisels at the exact angles of 25° and 30° needed to achieve the correct bevel/edge. Sharpening chisels and plane blades became much quicker, easier and more accurate with a 'sharpening jig'. I now had no excuse for working with blunt tools!Tools required:Chisel and plane sharpening with a oil/diamond whetstoneTo sharpen a chisel or plane iron with a normal stone and a honing guide follow these simple steps. The same steps are applied whether you are using a coarse, medium or fine abrasive, coarse is only really needed if you are grinding the blade after having hit a nail or hard know etc that has dented the tools cutting edge; Step 1: Fix down the Oil or wet stone base Most stones come stored in a box that when the stone is removed from can be screwed down to a workpiece or scrap timber. Do this first to keep the stone from moving and sliding around whilst sharpening the blades.Step 2: Oil or wet the stone Using water or oil lubricate the stone ready for grinding. Wipe off any excess and keep more oil/water handy for later, as well as a rag that can be used to clean off the stone. At any point during sharpening if the stone becomes dry or particularly dirty clean it off straight away and relubricate.Step 3: Place chisel in honing guide, set the angle Slide the chisel or plane iron into the honing guide and tighten it so it if held but loose enough to be adjusted. My honing guide has measurements written on it that blades should protrude in order to achieve the desired angle. Using that or the instructions for your honing gauge if they are different set the blade at the desired angle, 25° for grinding or 30° for honing.Step 4: Begin Chisel sharpening Slide the tool and guide over the stone backwards and forwards keeping the chisel edge firmly in contact with the stone. As much as is possible with straight wheels try to use the whole stone working slowly from left to right whilst going backwards and forwards.Step 5: Clean off the burr After a short while a burr will appear on the underside of the blade. Turn it over so it is flat and again slide it from side to side over the stone.Step 6: Repeat process and clean up Repeat the process above until the desired cutting edge is achieved. When happy remove, clean and dry everything off. Finally place all the chisels in your chisel roll That is a fairly slow and painstaking process if like me you have more than 10 chisels. When dull, I need to sharpen my tools as quickly and easily as possible and get back to work which is why I bought a Trend chisel sharpener. Chisel sharpening related pages Chisels Hand Planes Back to carpentry hand tools Leave Chisel Sharpening and return to carpentry tips and tricks home page |
to keep them safe and sharp.