My adventure with automatic sharpening started when I went to a country auction a couple of summers ago. The auction was in a hamlet with no stores, and it wasn't obvious where the residents worked. The seller was one of those guys who lived in the house for his entire adult life and accumulated stuff for over 50 years. At some point he had run a sharpening business out of his house. The homeowner, now about 80 years old, lived in a space of a few hundred square feet, with the rest of the house, garages, and other outbuildings stacked to the ceiling with machines, including a large metal-working lathe, tools, lumber, papers, dozens of broken chairs, and garbage. And he could probably tell where everything was. The front yard was covered with tools, some on tables, others on the ground. The auctioneer had a tent in case of rain -- which didn't happen -- and next to that was what must have been a 35-foot-long Dumpster, filled six-feet deep with junk that didn't make it to the auction. I took my number and waited for the sale to start.

 

I picked up lots of saws for $5 a bundle, a couple of little things I don't recall, and near the end of the night they got to the saw filing machines. The auctioneer couldn't get scrap value for a practically new-looking Foley-Belsaw carbide sharpening machine that costs a fortune new. It looked heavy, and it wasn't what I was looking for. When the opening bid got down to $50 and no one bit, the auctioneer moved on. I went for the older saw machines. There were two model 61 filers. I started at $20 and another bidder jumped in. I bailed out at $50, so he got it. No one else was interested, so I got the auctioneer to go down to $35 on the other, and it was mine. I carried it to the truck after the sale and carted it home, arriving just as the rain came in.

 

Foley automatic saw filers first came out at the turn of the 20th century, the early ones operating with a hand crank. The first machines were designed to sharpen butcher saws. With time, the filers became more flexible in the variety of saws they could sharpen. The F-3 was introduced in 1919 and the F-5 in 1926. The latter could use an optional electric motor. The F-16 filer (sold 1932-1954), looks much like the 61, but lacks a few features. The Model 61 is primarily a motor-driven machine. It has a small knob on the drive pulley in place of a crank, which is used to check the adjustments without engaging the motor and possibly damaging the saw. The major functions of my post-World-War-II filer are the same as those from the early part of the century. The saw is held in a carrier, which a steel bar with three or four clamps that hold the saw. They came in a few lengths and shapes to accommodate different types of saws, both flat and breasted profile.

 

A simple pair of gauges position the saw on the carrier so that the teeth are the right height in the vise and the file can sharpen the teeth. The carrier then rides on a pair of wheels that allow the saw to advance to the next tooth as it is sharpened. Once the carrier is put onto the machine, the vise is tightened onto the saw blade. The bevel of the teeth is set on a scale on the back of the filer, which pivots on an axis at the front of the machine.

 

The teeth's rake angle is set by rotating the cylindrical stocks that hold the file, and the setting is held by clamping the stocks. The height of the file in relation to the saw is set with knurled screws that adjust and clamp the file holders in the filing arm. Rotating the drive pulley pushes the file across the teeth. At the end of the forward stroke, the filing arm lifts the file off the saw teeth, the arm slides back, and the tip of the file is brought back down into filing position.

 

The other motion the machine makes is advancing the saw to the next tooth to be filed. When the file arm lifts to slide back, the advance mechanism slides the saw to put the next tooth into the path of the file. As is the case with manual saw filing, every other tooth on a crosscut saw is filed because of the alternating bevels on the teeth. The filer will then go back and file the other half of the teeth later, filing in the opposite direction. One end of the advance mechanism rests on a table above the filing arm. The other end has a finger that rests in the saw tooth gullet. When the filing arm lifts, the advance mechanism pivots in the middle, and the saw is advanced by the finger of the mechanism. The distance the saw is advanced depends on the number of teeth per inch. The distance is adjusted with two set screws, one setting the starting point for the finger and the other regulating the distance the mechanism moves. It's all simple, but the adjustment is trial and error and must be checked for each saw. The adjustment sometimes needs tweaking during the filing process.

 

The success of automatic filing depends entirely on the perfect regulation of saw teeth. In other words, the teeth must be evenly spaced because the filer doesn't control the spacing of the teeth. The opposite is true: The filer is controlled by the spacing of the teeth that are already on the saw. Unevenly spaced teeth make the file skip to the wrong tooth or land on top of a tooth, resulting in a messed-up saw.

 

Poorly regulated saw teeth are jointed down and new teeth are stamped out with a separate machine called a saw toother. They turn up on ebay and in other auctions all the time, but usually don't have the guides that control the number of teeth or points per inch. A toother is pretty much useless without them, and they sell cheap because of it. When all is well and the filer goes neatly from tooth to tooth, the teeth are evenly filed. It might take a couple of passes to do it right. Filing too deeply in a single pass will do a rough job and likely gore the teeth off the file.

 

Once every second tooth has been filed the right amount, it's necessary to file the other half of the saw's teeth. The filer is designed to pivot so the bevel (or fleam as it's called) matches the teeth, the same as you would in manual saw filing. This adjustment, called the quadrant, pivots 30 degrees on each side of a line perpendicular to the saw. Half of the teeth are sharpened with the file pointing toward the toe of the saw, half with it pointing toward the heel. I had reservations about doing it that way because I've found during manual saw filing that I get better results by turning the saw so I'm always sharpening with the file pointed toward the toe. I find a saw tends to vibrate when I sharpen with the file pointed toward the heel.

 

What I decided to do was reverse the rotation of the motor and turn the file around, so it files toward me instead of away. It's quicker than remounting the saw in the carrier. It wasn't the intention of the manufacturer to do it that way, but it worked. Later I was informed of the proper way to use the machine and the results were fine. There is no need to turn the saw or reverse the file to sharpen with good results, and it's a fast process. You simply pivot the quadrant adjustment to allow the file to sharpen the other teeth. Some adjustment to the advance mechanism may be necessary, but practice makes that easy after a few saws. All of this would have come to me more quickly had I access to an instruction manual.

 

Notice the bar stock near the bottom of the machine in the first photo. The previous owner added it to stabilize the saw carrier. Just below it is the clamp for the vise. It is designed to slide up and down and doubles as an arbor to hold circular saw blades for filing. There is also another carrier meant to hold bandsaw blades. The blade loops around the filer and is fed in a continuous cycle until all the teeth are sharpened. The filer is also designed to joint the teeth, but I've not found any advantage to doing it that way, a mill file being much quicker. The real advantage to the automatic filer was the ability to file several carpenter's saws with 7 or 8 points per inch rapidly with minimal labor. Considering the cost of the Foley saw filer was $237 when the Model 61 came out in 1954, it wasn't a household tool. The price of the F-16 model was $222 in the late 1940's. Foley's sales brochures for potential buyers included marketing plans for sharpening businesses run in communities of all population sizes. It's entertaining to read the pamphlets to see how times have changed over the last 50 years. For example, adding a Foley key cutting machine to a sharpening shop could result in another dollar or two of income per day. I enjoy using my filer, but it's not something I couldn't live without in the shop. For the average galoot with a few saws, manual filing is efficient. With a little practice, manual filing is not difficult, and you can keep your saws sharp without spending a lot of time at it. Finally, I wonder how many years automatic handsaw filers were profitable, either for the manufacturer or the machines' users. The F-16 filer came out during the Great Depression when few could buy the machine and carpenters weren't working or paying to have their saws sharpened. Then came World War II and war production. There were probably not a lot of saw filers being sold or used. The building-boom period after the war must have been good for the sharpening business, but it wasn't long before electric circular saws became dominant on job sites. By the 1960's sharpening machines became specialized and more complex to handle the variety of cutting tools being used. Routers, shapers, and circular saws with carbide cutters replaced handsaws, chisels, and planes. The investment needed to equip a sharpening shop for these tools became enormous. The volume of work needed to pay for the modern machines requires a steady customer base of industrial clients. Walk-in business at a storefront shop is not going to keep the carbide sharpeners running, although I'm sure you can still take in a dollar or two a day cutting keys.     For more information about Foley filers, go to the Foley Filer Blogspot.          Published 2002.

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