Scalloped serrated knife with two sided bevel

[Elden]

Shown below are pictures of a serrated knife from a rummage sale. It has scalloped serrated teeth and is beveled on both sides.


What would you suggest for sharpening?

[Herman Trivilino]

Measure the edge angle with the angle master, divide by 2, and use your jig to grind that bevel on each side.  Prepare the grindstone fine so you remove as little material as possible.

[Elden]

Thanks Herman, but the bevels are not flat due to the scallops.

[Herman Trivilino]

Elden, measure the edge angle at the tip of one of the scallops.

[jeffs55]

Any amount of sharpening on those teeth is only going to flatten them. The round profile cannot be maintained, can it? A bread knife with round teeth is not much of a bread knife in my experience. It just will not cut througn a tough crust like one with points on it. Believe it or not, I have one of those 5 Star knife sets from Ronco and the bread knife it comes with is superb. Its only fault is the 10 inch or is it 8 inch blade. You say that ought to be long enough but it is not. I like to cut  my bread at an angle and that greatly increases the length of cut. Kborvo, buy you a nice cake slicer from Amazon for less than $20 delivered and it has a blade 14 inches long! It is made by Fat Daddio. I have one and it is nice. It has the pointed teeth if you ever need to sharpen it which is not likely just cutting bread and cake.

[Elden]

Thanks fellows. You are confirming what I figured. I did not get the knife to use it, but because of the oddity of it. Two others along with it (they are normal style serrated knives) cost a total of $1.00. All were purchased for training purposes.

Jeff, I wondered how well it would slice even if it were sharp. As you said, I can't picture it working well.

The only thing I can think of is using the leather honing wheel(s). I want to try to maintain the original profile just to see if I can, yet get it sharp. If I had a tiny flat hone, I think that would work to remove the dings. I may have to gently use my needle files to do that, then proceed to the honing.

[Jeff Farris]

.... I may have to gently use my needle files to do that, then proceed to the honing.

You're on the right track. I've seen this design (double bevel serration), but it is rare. I would attack it with a set of slip stones and then the leather honing wheel.


EDITED TO ADD:

Looking at a photo, it  is hard to judge the radii of the serrations. If you're looking to do this with the Tormek, I can tell you that you can use the smooth side of the stone grader to put a radius profile on the corner of the grindstone, which can then be used to fit into inside radii with freehand control. It's tricky, and I've buggered up as many tools doing this as I have saved. The usual problem is that the small radius surface doesn't stay as smooth as you want it to, and all the sudden you're cutting too fast.

But, if you bought it to practice on, there's one thing to practice.

[jeffs55]

Well for a dollar invested I would say you got your moneys worth. I bought a new bread knife at Publix with rounded teeth such as yours, it did not work well. I bought it because of its 12 inch blade but if it won't cut, it ain't worth it. Another lesson hopefully learned.

[Travis G]

Have fun with that.

The greatest success I've had with this type of serration is with a fine Scotch-brite deburring wheel on a high speed bench grinder. With the corner of the wheel, light to moderate passes are done on either side to create a burr (ironic that a deburring wheel can create a burr, but that's been my experience) which I then use a ceramic rod system (Spyderco Sharpmaker) to deburr and finish honing.

On the Tormek, I'd experiment with using the corner of the leather wheel. If you had the profiled wheels as well you may have even greater success. Another option is to use a diamond abrasive rod of some sort in lieu of the Scotch-brite deburring wheel, mentioned above, to form a burr, then finish and hone on the Tormek's leather wheel.

A lot of it has to do with the initial quality of the edge bevel. For example, Wusthof makes a knife called the Super Slicer which has reverse scallop serrations (single beveled, admittedly) like the knife above. The quality of finished edge we can get on one of those using my process listed above is exceptional.

For the record, we also use the Scotch-brite wheel for conventional scalloped serrations, but use the corner (radiused, not square) to fit into each serration and then deburr on the flat side.

Travis

[Elden]

Thanks for the suggestions Travis. I haven't tackled it yet. I do have the profiled leather honing wheels and had them in mind. I also have a tapered DMT diamond hone as well as DMT Aligner flat hones. I can see where the Scotch Brite wheel would probably work well. If I ever finish setting up the mandrel, I,also, should have a paper wheel setup with a support bar similar to the Tormek USB. I would think the corner of the paper wheel would work as well.