My Bread Knife

[Herman Trivilino]

My old Echo brand 8-inch bread knife has seen better days. I've posted about it before here in this forum. The conventional wisdom (we learned this from Jeff) is that these knives that are scalloped on only one side are sharpened by grinding the flat side. Well, I had done this so many times to this old Echo knife that it just wasn't working any more. Ken S and others encouraged me to take a round file, or a wooden dowel and diamond paste, and grind away at the scallops. Not having any diamond paste on hand I decided to glue some wet-o-dry sand paper to a wooden dowel and give that a go. The sand paper quickly wore out and then it tore.

Recently I purchased a Victorinox as a replacement. When I showed it to my wife she commented that we'd had that old Echo knife since before we were married. So I figured I'd take it to my local hardware store. They have a guy from Greater Houston Sharpening come and pick up stuff on Mondays, then return it sharpened the next Monday. They charge $3 plus $1 per inch, so that's $11 for this knife. They have a warning on their flyer that the depth of the scallops gets reduced with each sharpening, so I had my doubts. I figured that maybe they too only grind steel off the flat side. One way to find out is to give it a try.

I picked it up last week, bought a loaf of bread to celebrate, and headed home to surprise my wife. I was immediately disappointed by the first slice. Tried my new Victorinox and it cut much much better. Out to the shop and a look with the magnifier revealed that they had indeed ground on only the flat side, and their grinding marks didn't reach all the way to the edge! So I called the sharpening service and they had me leave it at the hardware store. Yesterday was Monday and I got a call from Mike at Greater Houston Sharpening. He said my knife was waiting at the hardware store to be returned to me with a refund of my $11. He's a really nice guy and explained that they hire teenagers and family members to sharpen, that he does the final inspection, and that somehow this one got by him.

I've talked to Mike before about sharpening in general and Tormeks in particular. He's sharpened a few of my table saw blades and a hand saw or two over the years. He confirmed that Jeff's method of grinding only the flat side is the correct method. He said that there's a new machine that costs $5000 that sharpens three types of scalloped edges, but he declined to buy it.

I asked about the wooden dowel method and told him that a 1/2 inch dowel matched the curvature of the scallops pretty well. He said that in that case you want to use something smaller so you can grind at the valley of the scallop and then roll the tool out towards the tips of the scallops as you sharpen. He recommended a round file made for metal and said that that Echo knife will have very hard steel.

He also mentioned that the Nicholson files are not being made any more, and that the alternatives from China are a waste of money. So, when I pick up my knife at the hardware store I'll be looking for a round Nicholson file. 3/8 inch. 

[Jan]

Herman, in this country, many knife sharpeners do not accept serrated knifes at all.

For my serrated bread knife I use diamond rod sharpener. One side of the sharpener is tapered rod, so you can select the appropriate segment, which corresponds to your serration size. I use the marker to delimit the part of the tapered rod, which should be involved in moving the sharpener back and forth for each serration. I also colour with a marker the bevel of each serration to see where my grinding occurs. With this care I believe the knife may survive functional for the next generation. 

Jan

P.S.: Diamond files may be used with a back and forth motion without damaging the file, but keeping in mind the burr formation, it is better to apply the pressure only during the forth motion.

[Ken S]

Excellent topic, Herman. Jan, your response was excellent, also. This topic hits many of the hot buttons of what is wrong with sharpening today.

Eleven US dollars strikes me as a fair price for sharpening a scalloped bread knife, providing the job is class A and done carefully by an experience sharpener. if the family member hired to do the job was a retired or moonlighting machinist, that would seem fine to me. If the teenager was an outstanding industrial art student majoring in the machinist trade, that would be fine, too. However, I doubt that was the case. Nothing personal against your friend, Herman, but the work was shoddy.

My opinions on sharpening scalloped blades are well known. I believe that grinding the back surface, although it is expedient, is not the proper way to sharpen a knife. Lee Valley and other places sell adhesive back fine grit abrasive paper especially designed for this kind of work. I don't believe ordinary wet and dry is up to the task. The adhesive paper I used did not tear. I used it with a 1/4" (6mm) dowel and only on the push stroke. Jan is right about burrs.

I have not yet tried it, however, I believe the diamond paste may be an improvement over the adhesive paper. My bread knife needs to be sharpened again; I will try the diamond paste and report.

I have read good reports about Grobet files, made in Switzerland. (lee Valley sells them.) Apparently they are of the high quality made famous by Nicholson for over a century before its decline. Too bad; they made fine products before they cheaped out.

Unfortunately, knife manufacturers seem more obsessed with their knives not staining than with how well they can be sharpened. The old high carbon knives worked very well if they were maintained. Now everything is stainless.

I think the smaller diameter dowels (1/4") are necessary to preserve the points of the scallops. With wider dowels the points would gradually be eliminated.

Herman, I hope you will return to rejuvenating your old knife with a quarter inch dowel and diamond paste. Your neighborhood Woodcraft would carry the date. A diamond file, like Jan recommends would probably work even better, although at a higher cost.

Ken

http://www.leevalley.com/US/Wood/page.aspx?p=58754&cat=1,43072

http://www.leevalley.com/US/Wood/page.aspx?p=58754&cat=1,43072

At the risk of sounding like an infomercial, Lee Valley is having one of its periodic "free shipping with orders over forty dollars" which ends the end of today.

[Rob]

I've been getting superb results of late with a diamond tapered file sold by Trend over here.  It's a 6 inch file with a handle, flat on one side and barrelled (half moon type convex radius) on the other both tapering to just less than a point.  So far I've used it to touch up my tungsten carbide tipped table sw blade which was as blunt as you like (80 teeth) and it'd really brought that back from the brink. Also just to tickle the edge of both skew and bowl gouge.

I was truly amazed at its performance with the bowl gouge. Using gentle circular motions all the way round the elliptical bevel it created a stunning edge for the finishing cuts.  What surprised me was how little pressure you have to apply to get it to cut.  I guess that's the power of diamonds.  I'm really impressed with the versatile little gadget and intend to try it on the gullets of my big bandsaw blades which go blunt after ripping green logs.

The tapered and radiused edge would be a good fit for scalloped knives I suspect though not tried it myself (I do it the lazy way and just grind the off side).

[Herman Trivilino]

As far as I know Nicholson still makes good files, it's just that they're going out of business. I picked up a round one at the hardware store yesterday.

Do you think this would work better?

http://www.amazon.com/Columbia-River-Knife-Tool-VEFF1/dp/B0030IX772/ref=sr_1_6?ie=UTF8&qid=1429118663&sr=8-6&keywords=diamond+tapered+sharpening+rod

[Rob]

http://www.trend-uk.com/en/UK/productlist/3/328/diamond_files_and_steels.html

4th product down (6" tapered file) is the one I'm referring to.

[Herman Trivilino]

Here are pictures of my sharpening progress. As you can see, I made a jig to keep the round (rat tail) file at the right angle as I filed away at the gullets. Then I used the Tormek to grind the flat side at a 20^o angle. I had to remove a lot of steel to reach the tips. Then I used the leather honing wheel on the flat side and the scalloped side. On the scalloped side I placed each gullet on the edge of the honing wheel. I've yet to use the knife to slice a loaf of bread.

[Rob]

be interesting to hear the result when you get chance.  Looks a thorough method, I'm sure it will work well. 

[Herman Trivilino]

I wasn't happy with the result so I filed on the gullets some more. I followed this up with a cylindrical stone attachment on a rotary tool. Then I ground the flat side on the Tormek grindstone again, prepared fine, to remove the burrs. I also briefly passed the scalloped side over the grindstone at the same angle to form little chisel tips at the high points of the scallops. After honing on the leather wheel I got something that now works well.

I compare to the new Victorinox bread knife that I bought recently. The flat side of that blade is completely flat, no bevel. The scallops on the other side each have an identical cylindrical shape. The geometry couldn't be simpler. There are burrs on the flat side left from the grinding that was done at the factory to form the scallops. I suppose these burrs improve the cutting action when slicing bread.

I wonder why these knives don't cut through skin easily. I'd think that the sharpened tips would be dangerous, but they aren't.

[Rob]

sounds good Herman....if a little labour intensive perhaps.  Talking of knoves that don't cut skin reminds of when I was recently in hospital with my youngest.  He's the one with all the leg bone troubles.  The nurses were cutting off an old plaster cast from his shin and the rotary blade tool (electric) was able to cut through the plaster like a knife through butter yet when placed on your skin it just tickled.  She demo'd it on the palm of my hand....couldn't believe my eyes, it just couldn't cut me no matter what she did and yet plunged straight into the plaster like an industrial chopsaw.  Amazing technology and I've no idea how they do that.

[Herman Trivilino]

sounds good Herman....if a little labour intensive perhaps. 

Yes, and a rather bold experiment, too. I could have easily ruined a knife doing this to it. But really, I figure that since I'd already given it to a reputable pro who couldn't do it, I had nothing to lose. To be honest, it now looks a bit like a key hole saw. I could probably use it to cut drywall. 

[Rob]

Underlying form trumps superficial beauty in my view.  If it's fit for purpose, who cares what it looks like 

[Ken S]

Almost all of my Nicholson files are older and were purchased as "old new stock" or used. They all have "Made in USA" stamped on them. I am not opposed to purchasing products made elsewhere, as long as the quality is good. With Nicholson, I have read reports that the quality has slipped since moving production overseas.

One big problem with hardware stores is that they are usually "bastard cut" (a perfectly acceptable term). Over the years the number of cuts has diminished to three, bastard, second cut, and smooth. Bastard cut is the coarsest cut. This is designed for quick removal of soft steel. A good industrial supply store will have all three grades, as well as a much larger variety of files. Second cut and smooth work much better with harder steels and leave a smoother finish.

Files are essential tools. Every shop should have at least a bare minimum a set of three mill files, one of each coarseness and all properly handled. The inexpensive Nicholson red plastic handles serve quite well.

Ken

[Herman Trivilino]

The round file I used to sharpen this bread knife is bastard. I could tell right away that it was far too coarse for the application.

[Herman Trivilino]

Over the years the number of cuts has diminished to three, bastard, second cut, and smooth. Bastard cut is the coarsest cut. This is designed for quick removal of soft steel. A good industrial supply store will have all three grades, as well as a much larger variety of files. Second cut and smooth work much better with harder steels and leave a smoother finish.

To what does the term "mill file" refer?