Where Am I?You are in the honing section of my pages on hand tool sharpening. If you have prepared the primary bevel on your plane blade and are ready to put an edge on it, you are in the right place. Other topics covered in these pages include the whole sharpening process, grinding, the FAQ, and plane blade testing.When you use a plane you wear the blade on both the front and back. It makes sense that honing restores the edge, on the front and back. Introduction
RecommendationsThere are some who say that you don't need a jig when sharpening hand tools. There are some who claim that this or that bench stone produces a fantastic edge. There are lots of stories about the old guy who sharpened up his tools on a bit of slate and got fantastic edges.If you want the best possible edges you must ignore all these stories.
VideosI am making a series of short videos showing details of building the station (glass sheets, jigs) and sharpening.Videos to date:
FeedbackHaving problems making or using anything? Something you think might be better explained using a video? Tell me about it.The Sharpening Setup
This is my current sharpening setup. Rather than try to fit pieces of different abrasive on a single large sheet of glass, I now use a separate piece of glass for each grit. In this picture, from left to right: 0.5 micron, 5 micron, 15 micron. I have three other sheets of glass with 40 micron, 1 micron and 0.3 micron. The plane iron is in the jig on the 15 micron sheet, ready for the first microbevel. You can see the small wooden slips on the other two sheets: 0.06" on the 5 micron, 0.10" on the 0.5 micron. The baby oil is in the upper left. Baby oil is repackaged mineral oil. Any light, non-volatile oil will do. The oil lets the filings float up off the abrasive and get pushed out of the honing zone by the blade. This keeps the honing area free of filings and thus able to cut as it was designed to do. [Most mineral oil sold for medicinal purposes will be too thick - it won't work at all. Baby oil is just the right consistency.] The combination square is set to the correct extension for this blade. The screwdriver to tighten/loosen the jig. Not shown -- the rags you will need to clean the oil and filings from the abrasive. I bought a cheap plastic tool box to hold the glass sheets when not in use. The Jig![]() You can use these 4 1/4" X 11" abrasives with or without a jig. If you decide to use a jig, you can make one like mine, or buy a commercial jig. I started out using an eclipse jig, then switched to wooden jigs that simply slide on the glass. You can see a variety of jigs - commercial and shop made - at my Jigs page. The jig system includes two thin wooden slips: 0.06" and 0.10" thick.
Building a JigOnce you have the hardware (2 1" machine screws and t-nuts - I use #6 size) and the appropriate drills (depends on your hardware, see below), you should be able to build one (or three) jigs in 20 minutes.
You should be able to see that there are 4 different drills required. Working from the top to the bottom (the outside of the back jig to the outside of the bevel jig):
These sizes work for me, but you should check each drill size on scrap before doing the jig. I own a HSS drill bit set sized in 64ths that was pretty cheap. Single Forstner bits are now available for a couple of dollars each at the local hardware store - no need to buy expensive bits here or a set of bits. Now, in detail.
The Slips![]() Start with a flat 2 x 6 of some softwood (I had a cedar plank). Cut a slot across the width near one end 1/4" deep and just over 3/4" wide. Prepare a hardwood (I used maple; it should be fine grained) stop 3/4" width by 3/8" thick and attach it in the slot with countersunk screws. Plane the stop down until it rises above the board surface just less than the thinnest slip you will be making. I have several stops - one for very thin slips, one for thicker slips, one for use as a planing stop when planing thick stock. For thick slips, you can start with a single longish piece of about the right thickness. For very thin slips I have found that a longish piece will flex during planing. In the model I show two thin pieces of wood: the back slip serves to balance the plane. Work the two alternately, keeping them about the same thickness, as you plane down to the desired slip thickness. This planing board works for the thin side of the jig as well.
If you make a lot of slips of the same thickness, a slotted board like this makes sense. If you are making just a couple of slips then working against a stop as above is perhaps a little quicker. Simplified Jig - The Quickie![]() Any jig is better than no jig, so I have developed a very easy to make version for people to try out. The jig is accurate and easy to make, but may not be as durable as my standard jig. Rather than us T-nuts, this jig relies on the holding strength of machine screw threads in wood. Mine has been used between 30 and 50 times and shows no signs of failure. Start with a nominal 3" dimensioned lumber board (hardwood better, softwood will do) 1" longer than your iron is wide. If you are making a jig for irons for a #8 (2 5/8" wide) you need about 3 5/8" long. The grain runs horizontally in this model. Remove the rounded corners (joint the edges) found on dimensioned lumber. Make sure the resulting block has constant width. In doing this you reduce the width of your 3" lumber from 2 1/2" to around 2". The exact width does not matter too much, as long as it is constant along the board. [It is much easier to joint a 12" long board to constant width than a 3 5/8" board - make 3 or 4 jigs and once and give some away.] [You will need to use whatever width you end up with as the large jaw height in the Extension calculator.] For short tools, the 2" tall jig you get may be too tall. Select stock width depending on your tool lengths.
You are also slightly better off with plain sawn than quarter sawn wood for the large jaw. The screws will come in from the top. A screw driven tangent to the grain holds better than one driven perpendicular to the grain. A screw driven tangent to the gain is also slightly less likely to split the wood. I have made a quickie like this with the grain vertical - so the screws were threaded into end grain. The wood is a very hard tropical and the screws still hold, even though tapped into end grain, after many uses. Use masking tape to clamp the two jaws together. Mark for holes 3/8" in from ends, in the middle of the thin side. Using a drill bit just a little smaller than the 1 1/2" flat head machine screws you are going to use, drill the holes. Test the drill bit on a piece of scrap. You need to check that you can screw the machine screw into the hole without splitting the wood. You also want to make sure the hole is small enough that the screw has good holding strength. Again, use a tap if you have one, or simply use the machine screw as its own tap. Countersink the machine screw heads into the thin jaw. [Jig positioned to show countersink holes in thin jaw. Thanks to Brian Rytel for a little tutorial.] If you have suitable taps, use them. If not, you should be able to drive the machine screws into the holes, using them to tap their own threads. Even if you use the screw as a tap this should provide lots of grip for many tightenings. You are ready to try your jig. Measure the two jaws and use those numbers in the extension calculator. The Glass SheetsI used to use a single large glass sheet, but have switched to one piece of glass for each half abrasive sheet. The glass dimensions: 5mm thick, 6" wide, 16" long. Plate glass (window glass which you can buy at most glass shops) is just fine, no need for tempered glass. At local shops they charge for glass by area, with no extra charge for cutting. I just show up with a list of sizes and they cut it while I wait. Your yellow pages should have a list of shops under Glass, Window. Google can find them for you if you do a search on Glass, Window with the name of your town. [Some people recommend marble tiles instead of glass. Glass is always glass. Marble you buy is almost certainly not marble. Natural marble is probably too soft and probably not flat. Artificial marble can be just about anything. Stick with glass.]Soften the edges of the glass sheet with sandpaper before anything else. From the glass shop it can be pretty sharp. A few seconds with sandpaper will prevent nicks later. I now glue the glass permanently to 1/4" hardboard - Masonite in this case - with Weldbond glue.
The glue will cure by the next day. The backing board is more to protect the glass during handling than prevent the glass from bending under pressure - the bench is the real support. The AbrasivesAbrasives are discussed in many places in these pages.Fitting the Abrasive sheetI have made 3 videos -- 15 micron, 5 micron, 0.3 micron -- of me sticking various abrasives to glass. In the video I use a spray bottle to wet the glass. I put all three on YouTube in hopes that with three you could see all the possible problems and solutions.In words:
Removing worn abrasiveAfter some use the front part of the abrasive sheet will cut more slowly.In fact, there are two big changes in how fast the abrasive cuts. When you start with fresh paper, it cuts very quickly. This is because the very small number of very large bits of abrasive are doing all the work, and doing it quickly. This is actually a bad thing. In any fresh abrasive sheet there are a few much larger pieces of grit. These pieces are well above the specified nominal grit size. This is a bad thing because these grits leave deep scratches and fracture the metal more than we expect (assuming the nominal grit size). Fresh abrasive acts as if it had a larger grit specification. During first use, these large grit particles will be broken off or will shatter. The result is a much more uniform abrasive surface with many grit particles coming in contact with the bevel. Once this initial high abrasive stage ends you enter a long period of pretty steady cutting speed. This is the ideal situation. Eventually the time taken to hone a microbevel gets too long and it is time to remove the worn abrasive at the front of the sheet. The PSA adhesive is very tough. You will have to get something sharp under the front corner to lift it a little. Perhaps you have a plane iron handy? I use a plane iron, bevel down.
Typical sharpening sessionMost people know how to sharpen, so this part won't break any new ground. Since I do use a jig, people who have not used a jig might get some ideas from the step by step discussion.If a short movie would help, you can watch me set the extension here. A little tricky the first time, with a little practice you should be able to set the extension in under a minute. Get the extension you need from the extension calculator. Having gotten it you might write it on the jig. Set that extension on your combination square. With the iron in the jig, tighten the screws until iron can move in the jig, but not slip out. For me, this means tightening until the first resistance, then perhaps 1/10 of a turn. That is, almost no tightening at all. At this point, the blade will not drop out if you hold the jig with the blade facing down, but you can move it. With the ruler of the combination square against the jig and the iron against the square, set the extension. ![]() A little bit more tightening of both screws and I'm ready to sharpen. A little is perhaps another 1/10 of a turn. If the thin jaw is bowed, you have gone way too far. At this point, you could probably twist the blade in the jig if you really tried, but you won't apply any pressures like that while honing. [Even while grinding.] Perhaps surprisingly, the iron rarely slips inside the jig once the nuts are tightened. This wide beech jig has excellent grip. As well, even after hundreds sharpenings, the jig shows little wear from sliding on the glass and the glass in scratch free. Precision How accurate is this method of setting the angle? When I set the combination square, I split the mark (half under the head). If I get sloppy and miss the mark by 1/4 of the distance to the next mark (once you try this you will see that such an error is almost impossible), then the resulting angle is off by about 1/10th of a degree. There is no chance of error on the second and third microbevels. SharpeningFinally, ready to sharpen. A video of me honing a plane blade you might want to watch before or after (or instead of) reading the description below. The video is almost 3 minutes long - an average sharpening time for a blade with a reasonable primary. It would take longer if honing revealed problems with the primary.
![]() Lubricate the abrasive with a few drops of baby oil. How many drops is a few? Well, actually, more than a few. You want the full width of the blade to be pushing oil around, so squirt a line of baby oil across the paper about 2" from the lower edge. Rest the blade on the abrasive, in the baby oil and check that the blade is making contact with the paper across the width of the blade. As you pull backward (always begin with a pulling motion rather than a pushing motion and you won't tear the abrasive if there is a problem with the blade) with light pressure on the blade, the trail of baby oil left behind will not be uniform if one side of the blade is high. Check the blade for being square in the jig if you notice this. [Note: If the existing blade edge is not square to the sides, then the blade will not lie flat on the abrasive. If there is a very small problem, you can put a little extra pressure on the high side to bring the entire edge in contact with the abrasive.] In addition to moving forward and back, move from side to side so that you use the entire width of the abrasive sheet. You want even wear across the abrasive sheet. When you finish there will be three distinct regions of the abrasive.
When are you done? The nice thing about using a jig is that you can stop, check the microbevel, then resume honing at exactly the same angle. Do that regularly, each time wiping the baby oil off the bevel and looking for a uniform microbevel the full width of the blade.
If the blade has a freshly ground primary bevel, then you are done when the first micro bevel is between 1/32" and 1/16". There are images of the first microbevel here. If the blade has been honed before, then when you start the old 15 micron microbevel is resting on the abrasive, with the 5 micron, 0.5 micron and wear bevels actually up from the abrasive. As you work on the 15 micron abrasive, you hone metal away gradually removing the old 5 micron microbevel, then the old 0.5 micron microbevel, and finally the wear bevel. The wear bevel will be visible as a bright line at the edge until you are finished this step. Continue working on the 15 micron abrasive until the scratches reach the edge, across the full width of the blade.
The new 15 micron scratch bevel should look the same from side to side. If the bevel is wider on one side than the other, check the blade position in the jig. Do this early on in this step and each time you flip the blade over to do the back bevel.
There is no point honing the back until you have finished the front -- until the first microbevel reaches the edge. Flip the jig (and blade) over and work the back on 15 micron paper for a few seconds, again starting with a pulling motion. You are done when the scratches reach the edge, across the width of the blade (the wear bevel is no longer visible). Repeat front and back a couple of times.
There is usually a wire edge at this point. It is created when you hone the front bevel, then weakened when you hone the back bevel. Do not worry about removing it at this point.
![]() I put the slips in front of the appropriate abrasive before I start sharpening so I won't forget to use them. Since the honing on the 15 micron abrasive may have left a wire edge, always begin on the finer abrasives with a pull stroke. It will avoid ripping the abrasive. One pull seems to be enough, then you can use push pull strokes, moving from side to side on the abrasive to use the full width. Again, I use baby oil to let the filings float up from the surface and get pushed out of the honing area. It also helps me see the contact line of the iron and the abrasive. The filings include small shiny bits produced as the wire edge is honed off. When are you done? The visual check is the presence of a narrow shiny bevel right at the edge, across the full width of the blade. This microbevel is very narrow, perhaps only 1/100" wide. The 5 micron abrasive produces very fine scratches that reflect light better than the scratches produced by the 15 micron abrasive. The quality of the surface is not like the wear bevel though - rather than a bright line, the 5 micron microbevel is a smooth even strip at the edge. Why this works When you start honing the second microbevel on the 5 micron abrasive, the slip increases the angle enough that the blade is resting solely on the edge. The honing action begins right at the edge, and gradually widens this microbevel. Initially you are honing just a fraction of the previous microbevel (almost 0%?). Because you are honing such a narrow strip, metal removal is rapid even with the finer abrasive and the second microbevel widens quickly. The 5 micron abrasive removes metal at the edge to the depth necessary to completely remove the 15 micron scratches. As this second microbevel widens, the rate of widening slows. By the time this microbevel is half the width of the 15 micron microbevel, the widening rate has slowed to almost zero. The process is self limiting. If you did not use the slip, you would be attempting to hone the entire first microbevel with this much finer abrasive. You might remove some of the scratches left by the 15 micron abrasive, but you have to spend a lot longer than 1 minute to completely remove them. If there is a wire edge, it is touching the abrasive. If you begin with a push, you can easily rip the abrasive. So, always begin with a pulling motion. If you see the wire edge breaking off (silver flecks in the baby oil), repeat the pulling motion. Second back microbevel Flip and work the back bevel on the 5 micron paper with the jig on the first slip for a few seconds. The visual check for done is the presence of a narrow microbevel at the edge, across the full width of the back bevel. As in the first stroke on the front bevel, the first stroke on the back bevel should be a pull rather than a push. The slip has increased the angle, so the blade is resting on the edge alone. Any wire edge will cut the abrasive if you push first. It is at this point that the wire edge usually starts to break away - you will see small silver flecks in the oil. Repeat on front and back. I usually flip back and spend a few seconds on the front, then again on the back to complete removal of the wire edge. The wire edge is honed away by repeated back and front honing. ![]() Again enough baby oil to make it clear that the entire blade edge is in contact with the abrasive. Remember to pull first, to avoid having the (very much finer) wire edge (left by the 5 micron abrasive) rip the abrasive. When are you done? The visual check is the presence of an even narrower microbevel at the edge, across the full width of the blade. This microbevel should be about half as wide as the previous, and a little brighter. [When I first started doing this in 2002 I had no problem seeing this microbevel. These days I am not so sure. If the baby oil wake left by the blade shows that the full width is making contact with the abrasive, and you hone for 30 seconds, you are probably ok.] Flip and work the back bevel on the 0.5 micron paper with the jig on the second slip for a few seconds. Again, check for the new microbevel across the full width of the iron. Remember to pull first, to avoid having the wire edge rip the abrasive. Again, I usually flip back and spend a few seconds on the front, then the back again to complete the removal of the wire edge. Why this works When you start honing the third microbevel on the 0.5 micron abrasive, the slip increases the angle enough that the blade is resting solely on the edge. The honing action begins right at the edge, and gradually widens this microbevel. Initially you are honing just a fraction of the previous microbevel (almost 0%?). Because you are honing such a narrow strip, metal removal is rapid even with the finer abrasive and the third microbevel widens quickly. The 0.5 micron abrasive removes metal at the edge to the depth necessary to completely remove the 5 micron scratches. As this third microbevel widens, the rate of widening slows. By the time this microbevel is half the width of the 5 micron microbevel, the widening rate has slowed to almost zero. The process is self limiting. If you did not use the slip, you would be attempting to hone the entire second microbevel with this much finer abrasive. You might remove some of the scratches left by the 5 micron abrasive, but you have to spend a lot longer than 1 minute to completely remove them. If there is a wire edge, it is touching the abrasive. If you begin with a push, you can easily rip the abrasive. So, always begin with a pulling motion. If you see the wire edge breaking off (silver flecks in the baby oil), repeat the pulling motion. Cleanup -- 1 minute. Wipe the baby oil and iron filings off the three abrasives. I also wipe the baby oil and grit off the iron for each visual inspection. This helps keep the abrasives clean (especially the 15 micron, which produces most of the filings). TimingThe time taken on the 15 micron paper increases as the first microbevel gradually widens across the main front bevel. When this first bevel gets too wide I regrind the primary bevel. I am very careful when regrinding the primary bevel to not actually grind down to the edge. Rather I grind away most but not all of the existing 15 micron microbevel. To see pictures of the blade taken during grinding, look here. The time taken on the 5 micron and 0.5 micron papers does not change, since they always start from the same complete bevel produced by the previous grit. These second two microbevels are quick because they are very narrow. This means as well that the 5 micron and 0.5 micron papers wear out very slowly.
Jigs for SaleI no longer make and sell jigs.If you make a jig, it is almost as easy to make 6 as it is to make 1. If you make extras and want to sell them through these web pages, send along a picture and contact details. I will add that information to this site. People wanting to buy a jig can then get in touch on their own. Website Navigation
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