Foolproof tool sharpening

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When I worked as a bladesmith back in the before times, we used belt sanders for all of our sharpening. It is hands down the best method for getting a well honed edge.

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So how would this compare to, say, the sharpening attachment for my Dremel?

I too canā€™t use a sharpening stone well. Thanks for the recco!

May I also wax poetic about the old knife sharpening guy who would drive through the streets clanging this great old bell? The moms would come running out waving their utensils at the guy. Heā€™s do his work outside the back of the panel van and we kids would delight in his cool tools. Does that still happen anywhere?

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Man, back in SF the little grocery store next to me had a knife sharpener come around once a week to do their deli knives, and then he started doing an overnight (or maybe it was a week) drop off service. That was awesome. Most importantly for me, he did ceramics. Iā€™m having a hell of a time finding anything in Tucson, even a shop to go to. Thereā€™s a guy or two wandering around to Farmerā€™s Markets, but they donā€™t have schedules, and Iā€™m not sure they carry diamond belts with them.

Iā€™d be tempted to get one of these, but at $96+ for the machine and belts thatā€™s two brand new knives, and I know Iā€™m not a professional, and any sharpening job I do will be inferior.

For the same money or less, you can get a benchtop sander with a 30" x 1" belt and a 5" disc. Mine cost around $50. It will do all the jobs described and more. The only advantage I see to this thing is that itā€™s pretty small, so you might be able to use it on hard-to-reach mower blades without dismounting them.

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I did not know it was possible to sharpen serrated blades. Iā€™m guessing my cake knife (can cut angel food cake without compression) is still out of bounds.

Not that Iā€™m going to spend nearly $100 for this tool, but I have learned something today so it was a good thing to read this thread.

In case someone questions my choice to spend money on such specific knives (but not sharpening them): I inherited all of my grandfatherā€™s and uncleā€™s knives. They were both avid chefs, and the tools in their kitchens were indicative of their skill level.

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Iā€™ve found that it is hard to make a straight and even edge with a dremel. It requires a deft hand not to over-grind any part of the blade. I love the Dremel for sharpening my lawnmower blades, axes, etcā€¦, but Iā€™m a little wary about using it on smaller blades that I intended to do fine work with.

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Iā€™d suggest Dremel with a barrel-shaped grinding tip with suitable diameter, and quite some patience, tooth by tooth. (Assuming the serrations have some sane spacing.)

Practice on cheaper less important blades, it will come to you in few years. Draw the blade over a grinding wheel in smooth not too slow strokes; too slow will introduce the overgrind irregularities.

With diamond wheels you can grind even carbide inserts for lathe tools.

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Is this a legitimate article or an ad? One has to be careful nowadays.

In my cousins town, they had what they called ā€œThe Umbrella Manā€ who rang a brass hand bell. He would take your umbrella for repairs. And I think the had a treadle grinding wheel slung on his back. If you look online, you can see many variations of this in developing countries, often using a bicycle as mobile workshop and store.

The best method I know for sharpening serrated blades of all types is to use a rat tail file on the scalloped (serrated) side and flat sanding on the opposite. If both sides have scallops, you will need to file both sides. I prefer this over something like a power tool simply because it is very easy to remove too much material with one which shortens the ā€˜spikesā€™ between each scallop and will eventually ruin the blade.

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Ceramic rods of appropriate sizes do a good job on most serrated blades, but the micro-serrated ones are pretty much unsharpenable without losing the tiny teeth. They last for decades, though.

If your angel food cake knife is one of the ones that looks like an afro pick, I donā€™t think anybody sharpens those. I could do it on my belt sander, but itā€™d be difficult enough that Iā€™d rather buy a new one and give the dull one to somebody with a poodle that needed combing.

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This is your ultimate touchup tool right here - the Big John Super Stick. Big enough for the largest blade and costs under $10ā€¦ Give one of these to everyone you know for Christmas and people will rave about it.

http://www.smkw.com/webapp/eCommerce/products/Smoky+Mountain+Knife+Works/Big+John+Super+Stick%26%23153%3B+Ceramic+Sharpening+Rod/SI1000.html

If you want to get good at sharpening knifes, buy some cheap flea market machetes (the smallest ones). Then use a bastard file once, and then a mill file to start getting an edge. Buy your files at flea markets and get old American files because the Indian and Chinese files arenā€™t worth shit. As you progress, cover the bladeā€™s edge with Sharpie ink - now you will see all the different angles your screwing up as you hack away at the blade. When you get close, use a small stone or diamond card to take down high spots. Then you can finish up with the rod. If it just refuses to get sharp, you have not removed enough metal with the mill file. Work under an intense LED light and use a magnifiers so you see the edge taking shape.

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The other thing about using sanders and buffers on blades is safety first. Itā€™s all too easy to nearly sever a finger when a loose sharp blade is under the influence of a motor.

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I know, we used to have a guy that did that in front of a store by me, but heā€™s not there anymoreā€¦
I bought one of those Chefā€™s Choice sharpeners which are OK, but not that great. Might have to give this one a try.

The spacing would be measured in micrometers, soā€¦no!

I think the need for an incredibly consistent angle when sharpening on bench stones is over stated. Iā€™m pretty good at doing that, but Iā€™m definitely not totally consistent, and my knives are plenty sharp. Like cut effortlessly though your fingernail when you miss the mushroom sharp. And there are plenty of guys deliberately putting different angles on different parts of their blades. Narrower angle at the tip for sharp point work, wider at the base for durability when hacking or doing heavy cutting. This is in fact where my inconsistency bites me in the ass. I tend to over thing the metal at the tips of knives (especially long ones) while still leaving them with a fairly wide angle that isnā€™t as sharp as I like. But if you can be constantly inconsistent, in the right way, it can be a good thing.

In terms of this tool the biggest problem I can see with it is that the bands are very narrow. Looking around it looks like theyā€™re 1/2". Using a cutting surface that narrow, on a machine, and with coarse grits, its relatively easy to remove more metal from certain parts of the blade than others along the length of the cutting edge. This can cause the blade to ā€œsmileā€ and warp in various ways. It becomes more apparent over time, but eventually you end up with a blade where the shape of the cutting edge has changed, or that doesnā€™t sit flat against the board when pressed down sideways. That can cause chipping and breakage where the metal has been overly thinned, and can definitely effect the cutting properties of a kitchen knife. Same thing can happen working with stones. But its much more likely, and would happen faster with something like this.

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Your comment made me spend some time on Google Images. I now know what youā€™re talking about, and no, it isnā€™t that kind. In fact, I cannot find an exact image of this particular knife. Guess itā€™s as special as my grandpa was!

This is as close as I could find, but mine is longer and narrower with a different handle and has a prong on the end as well. The brand is Cattaraugus Cutlery (New York, 1886-1963):

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Yep, and if you get the blade stuck between the stationary and rotary parts, thereā€™s a distinct possibility things might get explosively dangerous faster than you can hit the off switch. A burnt-up motor is the least of your worries! Half a pound of stone flying at your face is far too exciting, and a snapped belt isnā€™t necessarily much fun either.

People think Iā€™m pretty blasĆ© about danger, but I wear expensive safety glasses or a full face shield whenever I use a bench grinder or sander, and I have foot switches on several of my big tools.

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