Wet GrindingTo establish the bevel of a cutting tool I use a slow speed wet grinder. Mine is manufactured by Jet and has served me well for the past few years. I like the wet grinder over a dry one for a few reasons. Number one: theres no choice in hell youll ever burn an edge on this machine and two, it has a nice tranquil watery sound when its running...kind of like a cool mountain brook. (just kidding) The Jet model has a speed control and a torque which I find extremely useful. To begin, Ill clamp the iron into the jig/holder which came with the unit. A quick set-up and were off...I apply moderate pressure here and work the edge back and forth so not to wear one side of the wheel more than the other. A minute or two and Im done. Take it out of the jig and dry it off. A quick look to see how youve done and were on to the water stones.
Water StonesI use three different grades of water stones; all by Norton. These cut really fast and are a pleasure to use. A 1000 grit, a 1000/4000 combination stone and finally an 8000. I decided to go with the 1000/4000 combination stone because I want to keep my stones dressed before, during and after every use. Before starting Ill take my 1000 stone and dress it with the 1000 side of the combination stone. Then while Im using it Ill continue to dress it every few minutes. This will ensure youre stones stay flat; the most important point when dealing with water stones. I like to check the bevel to confirm Ill be setting up my honing guide properly. In this case Im sharpening my Iron from my jointing plane which has a 35 degree bevel. This is a high angle that takes care of difficult grain and leaves very little if any tear out. The whole stone dressing thing is something I picked up from Rob Cosman, he has a great sharpening video out thats worth watching. One aspect where I differ from Rob is he free hands when sharpening and Ill use a honing guide. Ive sharpened without the guide but feel that sometimes Id get small discrepancies in my bevel...the honing guide is reliable, easy to use and doesnt take much more time to set up and use. If you can reliably sharpen by hand and achieve favourable results every time, than do it. If youre like me though and may wander off a little while trying to establish a main bevel, secondary bevel and finally a micro-bevel on your edge, then use a guide. David Charlesworth address this point on using honing guides quite well in one of his books...I believe its volume two.?
Honing Guide set-upThe Veritas® Mk.II Honing Guide is a great jig for repeated, reliable sharpening. First time users may have a slight learning curve with its set up but once or twice and itll be second nature. Once Ive determined my bevel angle Ill take the registration jig that comes with the tool and set it for this 35 degree, high angle bevel. One other nice thing about this jig is you can do high angles, standard angles as well as back-bevels with a simple adjustment. So now we have the desired angle we can slide the registration jig onto the main body of the guide and lightly tighten it. When doing this part theres small registration lines so you can set it to the desired width depending on what size blade your sharpening. In this case its just over 2". Next, flip the jig over and slide your plane iron in. The registration guide makes it error proof to square up the iron and establish the proper length protruding from the guide. Tighten up the blade clamp knobs and were ready to go. One other point to mention is before you start, double check the micro-bevel knob; make sure when starting on your 1000 grit stone its in the 12:00 position. Then after each stone grit youll go from 12 to 3 to finally 6:00 finishing on the 8000 stone. This is what establishes the standard bevel, a secondary bevel and finally the third micro-bevel which at that point will cut the hair off of your arm! Lets begin...
I splash a bit more water on the stone after Ive dressed it before beginning. Apply moderate, consistent pressure and gently move back and forth over the 1000 grit stone. Be careful when you first touch the Iron to the stone you dont dig into it. I alchoices like to begin by placing the edge of the Iron at the top, furthest point of the stone and gently draw the guide back towards my body. Then on the first couple of push strokes Im careful not to rock the jig. A few passes and youll start to feel the primary bevel becoming established. The water will actually start to grab the tiny edge and suck it into the stones surface. A minute or two at most and Ill grab my combination stone and re-dress the surface using the 1000 grit side. Rotate the stones frequently while you work checking the bevel often. Another minute or two and were done. Again before putting the 1000 grit stone back into a water bath, dress it quickly with the combination stone. Next Ill insert the combination stone, 4000 grit side now, and adjust the micro-bevel knob to the 3:00 position. Now were gently working on this secondary bevel. A minute and were done. Again, dress the stones and move on to the 8000 grit. This final stone is quite soft and should be used with great care. The same procedure applies but I try to take some extra precautions while using it. Before I start Ill again reset the micro bevel knob to its final position at 6:00. This creates a tiny micro-bevel that when properly done will scare you; this is really sharp! Another minute or two is all thats needed to establish this final bevel; when complete, carefully remove the Iron from the jig and dress the stone again. Another small splash of water and we can hone the back surface of the blade.
Moderate pressure and even strokes up and down the stone will insure desirable results. I constantly flip the stone end for end and redress often. Flattening the back of a new blade may take up to 10 minutes like this. Keep re-applying water, turning the stone over to wear both sides and try to use the entire surface of the water stones.The Iron Im working on today has already been properly flattened and only requires a few seconds to cut-achoice the tiny burr left behind from the previous steps. When I can see my ugly mug in the reflection, Im done! Time to put it to work. Carefully dry the Iron and insert it back into the body of the plane being sure not to catch the edge on the choice. This final picture shows some shavings from a piece of Walnut. These are end grain shavings! This is really sharp and the entire process Ive just described took no more than 4 to 6 minutes at best.
Cheers!
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