Episode # 3: Layout Tools 06/26/2009
Whenever hand tools are discussed, handsaws, planes and chisels take center stage. However, without the layout tools, none of these tools would be able to do their jobs accurately. Still the layout tools just don't get the attention they deserve so I'm dedicating Episode # 3 just to them. I touch on what to look for when you're shopping for them, how to check them for accuracy and how to use them properly. Filing Saw Teeth 06/24/2009
 With the construction of the saws completed, all that was left to do was to file in the teeth. Commercial saw manufacturers typically cut the teeth in with a machine, resulting in perfectly spaced teeth. I don't have this equipment, nor do I wish to invest in it, so I use a file. I think teeth that are hand filed in end up working a little more smoothly anyway due to the minor variation in spacing that results from hand filing in the teeth. The random spacing theoretically reduces harmonic chatter, if only slightly. In my experience using saws in which I've filed in the teeth compared to saws I have with machine cut (but hand filed) teeth, I can notice a slight difference, but it is only slight. I set the tooth spacing by drawing lines with a CAD program and printing it out full scale. I place the piece of paper in the vise with the saw plate and file a small notch at each line. This one happens to be 12 PPI (or 11 TPI).  Once I've filed a notch at each gullet location by making one or two passes with the file, I remove the paper. I then go back and make several more passes at each notch to deepen the gullet and rough shape each tooth. At this point, I'm just trying to get close to the final rake angle so I don't use a guide to set the angle of the file. In fact, I'm just trying to keep the front of each tooth vertical at this point (i.e. 0 degrees of rake) and I do this by eye. I file just until the flats on top of each tooth disappear or almost disappear and no further. I file the initial notches and shape all the teeth from one side of the saw plate, prior to setting the teeth. Once all of the teeth have been rough shaped, I set the teeth. I use a plier type saw set for this. I begin at the heel of the saw and work toward the toe setting every other tooth. I'm just trying to set the top 1/3 or so of each tooth, not the entire tooth. If you try to set the entire tooth, you might break them off. Once I've reached the toe, I flip the saw around in the vise and set the remaining teeth so that each tooth is alternately set when I'm done. If you make a mistake and set two teeth in a row in the same direction, don't worry about it. It won't affect the performance of the saw and it can always be fixed at a future sharpening if needed. Do not try to set a tooth in the opposite direction of it's original set or you are about gauranteed to break the tooth off.  After I have set the teeth, I like to joint them lightly with just one or two light passes with a 6" mil file. I hold the file tight to a block of wood which acts as a fence to keep the file square to the tooth line. This seems counter productive to the initial shaping I just worked so hard to do, but jointing lightly after setting the teeth ensures that each tooth will be the same height after sharpening, even if the set is a little uneven. It also provides a reference flat on top of each tooth to guide my final filing.  Another aid for doing the final filing of the teeth is to darken the flats from jointing. You can use a permanent marker for this, and I did for years, but the teeth tend to chew up the marker tip pretty quickly so you never really use a marker until the ink is gone. Machinists layout dye is another good option, however, it's awful messy. My solution is to use an old planemaker's trick, a candle. By running the saw teeth back and fourth several times through the flame of a regular old candle, you coat the saw teeth with a thin coat of soot. The dull black soot covers well and provides a good reference for teeth that have been filed and those that have not. You don't hold the candle in one spot for so long that the saw plate heats up (this could ruin the temper of the steel) rather you keep the candle moving continuously to "paint" on the soot.  With the teeth coated in soot, I begin the final filing and sharpening of the teeth. Now that the teeth are set, I can't just file all of the teeth from the same side. I need to file only the teeth that are leaning away from me. I also now use a guide block to guide the angle of the file in order to set the desired rake angle. Here, it's about 4 degrees. The guide block is simply a small scrap of soft wood with a small pilot hole drilled centered on each edge. I then draw a line tangent to the hole at the desired rake angle. The rake angle should lean toward the handle. So in this picture you can see how I've noted on the guide block which side the handle needs to be on. The rake angle leans toward the handle from bottom left to top right at an angle of 4 degrees from vertical (the opposite edge of the guide block is a mirror image of this edge). I insert the file into the pilot hole with the right side flat parallel to the rake angle line. All I need to do now is file with the wood block held level and I will maintain the 4 degree rake angle. Again, I start at the heel and work toward the toe, filing every other tooth (only those leaning away from me). I file straight across (90 degrees) the saw plate because these are rip teeth. I make only one or two passes on each tooth until the flats on top of each tooth are smaller by about half. Be careful because this goes faster than you might think, especially on these smaller teeth. It takes only one or two light strokes of the file.  Here you can see where every other gullet has been filed as noted by the shiny gullet. The candle soot remains on the unfiled teeth. Once I reach the toe, I flip the saw around in the vise so that the unfiled teeth, which were leaning toward me before, are now leaning away from me and the saw handle is on the left. I NOW REVERSE THE GUIDE BLOCK ON THE FILE. The opposite side of the guide block is a mirror image of the first side. It has an arrow pointing to the left where the handle should now be and the rake angle is tangent to the left side of the hole and should lean from the bottom right to the top left at 4 degrees from vertical. The file is inserted with it's left edge parallel to the rake angle line. This is an extremely important step. If you keep the guide block in the same orientation as before, the rake angle will be all wrong and when you file the teeth you'll end up filing them into little toothpick points, so make sure you reset the file in the guide block so that the rake angle is correct.  With the guide block on the file switched to its proper orientation and the saw flipped around in the vise, I can now file the remaining teeth. Again, I start from the heel and work toward the toe filing straight across because these are rip teeth. I file only until the flats on top of each tooth disappear and no further, even if the teeth are different sizes (the size isn't important, the final height is). Once I reach the toe, the filing is complete and the teeth should be very sharp. I perform one final step prior to using the saw. I like to joint the sides of the teeth to remove the filing burrs and smooth the teeth out some. To do this, I place the saw plate on the edge of my bench and with an oiled hard Arkansas slip stone, I make one pass with light pressure from heel to toe, keeping the stone flat to the side of the saw plate. I then flip the saw over and joint the other side the same way, making only one pass from heel to toe.  Once I've done the side jointing, I'm finished with the sharpening. I use a little turpentine on a rag to clean the remaining soot from the blade and the saw is ready to go back on it's peg until it's called on to cut some tenon cheeks. Here's a shot of the finished rip teeth. They're not perfectly spaced, not all exactly the same size and likely not all exactly the same rake angle, however, they don't need to be perfect and hand filed saws never are. In fact, the imperfections are what make hand filed saws such a pleasure to use. They cut smoothly with no vibration or chatter and seem to glide through the wood. If you don't already sharpen your own hand saws I hope this will encourage you to give it a try. It's really not that hard to do and if you just take it step by step and go slow it's very difficult to ruin a saw and near impossible to take it beyond repair. If you make a mistake, it's a simple task to rejoint the teeth down and start over. Oh yeah, and the obligatory test cut was smooth, fast and straight. Can't ask for any more than that ; )!  18th Century Style Tenon Saws Part II 06/22/2009
 With all of the rain we've been getting here on the East coast, I had some time to finish up my saws this weekend; well, except for filing the teeth. We left off the last pst with the backs finished and the plates cut to size and the bluing sanded off. Now I needed to insert the plates into the backs. I used a method described in the Grammercy saw kits by using a softwood "bat" to tap the plat into the back. I started at one corner and worked it down gradually.  This isn't as easy as it sounds. You have to tap and pivot and tap some more trying to keep one end in while you tap the other end down. The back holds the plate very tightly so you need to get it in exactly the right spot when you start it. It's too tight to slide the plate down after it's started without buckling the plate. It's sort of like West Side Story...fighting and dancing at the same time.  I did finally manage to get both done. The second one was slightly easier than the first, but not by much.  With the saw plates and back assembled, I turned my attention to the handles. I glued the templates I made to a piece of straight grained walnut with liquid hide glue.  I bored holes to locate the concave curves and finished cutting the blanks out with a turning saw. I cleaned up to the template lines with carving gouges, bench chisels and spokeshave. I also bored the holes for the split nuts and cut the kerf and mortsie for the saw plate while the stock was still flat. It's much easier to do this now.  With all the holes bored and the kerfs cut, all that was left to do was finish the shaping. I used a rasp, file and several grits of sandpaper to do this. This is the fun part. The best thing about making your own saw handles is that you can make them fit your hand perfectly. No sharp corners or pinch points, just a perfect smooth fit to your hand. I finished with a coat of linseed oil and I'll add several more over the next few days. I didn't take any pics of making the split nuts, however, the Norse Woodsmith has a good writeup on that and I used his method. The only difference in my split nuts is that I used lock washers in place of the square nut, ala the Grammercy saws. It's easier in my opinion and they aren't seen anyway. Now I just need to file the teeth. 18th Century Style Tenon Saws Part 1 06/16/2009
A few months ago I borrowed the book "Tools: Working Wood in the 18th Century" from my local library. This book was written by James Gaynor and Nancy Hagedorn in conjunction with Colonial Williamsburg. In that book was a picture of a group of tools, one of which is a saw by an unknown maker.  I have never been thrilled with my current tenon saw and have wanted to replace it for some time. Not having the money to spend on the style of saw I want, I decided to make one. Some time back I made a couple of dovetail saws as practice for the larger saw. When I saw this saw in the Williamsburg book, I knew right away that was the style I wanted to make. Based on the typical size of a dado plane, I estimate this saw plate to be about 19" long. I think that might be a little long for me for routine tenon work so I decided to make mine about 16".  So I ordered a piece of 0.025" thick 1095 spring steel from McMaster Carr. The cheapest length of the steel was enough for three saw plates so using a pair of aviation snips I cut the spring steel into a 14" piece for a crosscut backsaw, a 16" piece for a rip tenon saw and a 19" piece for a future saw TBD at a later date (maybe a 19" long Kenyon style tenon saw). I filed the cut edges to remove the rough cut edges and the deformed steel resulting from cutting the steel with the aviation snips. The steel comes blued but I decided to sand the bluing off down to the raw steel.  I made the backs like the backs for the second dovetail saw that I blogged about some months back. I started with 14 ga. steel angle and used an iron bench vise to close the bend. These 1" angle pieces were a little more difficult to completely close than the 3/4" angle and needed to be finished with a hammer on the anvil of my machinist vise. Unfortunately this left some marking on the backs that I had to file out.  So I clamped the back to the bench and draw filed each side to remove as much of the hammer marks as I could remove with moderate effort. This picture is part way through the process and you can see some of the low spots and spots that have been filed.  This picture shows where I stopped. There are still a few marks but they would be too much work to remove and require too much metal removal which would weaken the back too much so I decided it was not worth it to remove them. I also cut and filed the decorative curve into the front of the back and filed some small chamfers on the lower edge and around the curved front edge to dress it up a little and remove the rough sharp edges. Finally, I polished the back slightly on a stitched buffing wheel on the grinder dressed with emery compound. Episode # 2: Hand Tools for Every Shop 06/12/2009
For new woodworkers looking to start a hand tool shop or experienced power tool users looking to incorporate more hand work into their projects, selecting tools can be a daunting task. There are literally thousands of different hand tools out there to choose from and without at least some experience using the tools, it's hard to know which ones to get first. Episode # 1: Introduction 06/04/2009
Well, the podcast is up and running. Honestly, I'm not sure how I feel. A little excited, a little embarrassed and a little anxious. At any rate, there's no turning back now. The show must go on as they say. Desk Finished 06/01/2009
 Ever since the first time I read Roy Underhill's book "The Woodwright's Apprentice" I've wanted to build a version of his standing desk. I always thought it would be a great piece to have in the shop for making drawings, laying an open book or magazine or setting my coffee. It would also give me a logical place to keep pencils, scissors and other small odds and ends that typically get lost at the bottom of boxes and cabinets.  So over the last couple of weeks I finally got around to building one. I modified Roy's design slightly by adding a drawer to my desk. To do so I had to make the sides slightly higher and obviously add a bottom rail to the front under the drawer as well as a frame for the drawer to sit on. I also shortened the height about 3" from the drawing in the book as I'm pretty short and the original 48" height seemed just a little high for me to work at comfortably.  The piece is made of Eastern white pine, as with most of the pieces I make for the shop, because it's cheap, readily available where I live, cheap, easy to work, and oh yeah, cheap. I also like the look of it as long as it's not full of huge knots (a few pin knots are ok). The inside is currently just a big open space. I'll add a simple gallery in the future, but for now it will serve as extra storage. I'll also divide up the drawer in the future but that's a project for another day. I'm glad that I finally got around to making this piece. It is certainly a welcome addition to the shop and much better looking than the piece that used to occupy this space (ugly plywood junk cabinet). It's unfinished right now as I have not decided whether to just oil and wax it or give it a couple coats of milk paint and oil. I think I'll just leave it alone for now and let it get used to it's new home for awhile. The finish can wait. | CategoriesAll
November 2009
       
       
        
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