Does the small knife jig allow for shallow bevels since many Japanese knives have a cutting bevel of 15˚and should they need a secondary bevel to keep the main bevel narrow it is necessary to do this at 10˚?
I have seen the simple homemade jig that Herman Trivilino has made the so called (HK-50) that can aid these small angles and I am thinking that this will definitely deliver such angles .
The new Tormek SVM-00 would be great for re-edging small knives but I am not convinced about how shallow a bevel is possible with this?
Has anyone put the SVM-00 through tests on really shallow bevels such as the ones I mention ?
I haven't used the SVM-00 but it seems it would be able to handle angles as small at 10o.
I'm not sure what you mean by the primary bevel. Are you talking about the taper? If so, I don't know how to set the bevel angle when there's a taper using the SVM-45 or the SVM-00.
With the HK-50 you set the bevel angle, then measure the taper, subtract the difference, and reset the bevel angle.
In an earlier post I indicted my intention to purchase one of the SVM-00 jigs last month and review it. That trip was cancelled. I stopped in at my old dealer today intending to purchase the jig today. They did not have them yet. So, no progress to report.
Ken
Sharp Tools USA sent me a mass mailer indicating that they had sold out and are expecting another shipment on April 29.
I believe that pictures below describe what Leo is saying.
I believe that the angles on the second picture are mislabeled (angle AB should be 30 degrees, angle CD should be 40 degrees). If it is labeled the way they meant, that is one thinly sharpened knife! :D
To me the primary or secondary (or the back as the one picture is labeled) bevel neither one is the taper (relief) grind or the thinning of the blade done by the manufacturer. I suppose by the strictest definition of the word secondary the taper grind would be a secondary bevel. If that is to be used, I like our knives to be triple beveled as almost all our knives are factory taper ground.
These angles are approximately what I aim for on knives that I sharpen. These are not Japanese knives, I don't own any at the present.
Leo from what I read and understand, your Japanese knives will have smaller bevels than that shown above (per my added note). The angles you mention may apply but having never sharpened a Japanese knife, I can't tell you. Is yours beveled on one side only?
Welcome to the forum! Keep posting.
You could be correct about the angles being wrong, Elden. The drawing itself looks like it was done by someone with no training as a draftsman. I say that because the arcs representing the angles are not drawn with the correct radius.
As far as grinding a knife to that geometry goes, well, I just don't see how it's possible with a Tormek.
It looks to me like the geometry I saw with my 40X microscope on a utility knife blade. It it possible that this is a scalpel?
Not putting a protractor to it, it appears to be close to the normal representation. I noticed what you said about the arc as well, Herman.
I am pretty sure that the 15 and 20 degrees mentioned, were meant to refer to the angle formed if a center line was drawn perpendicularly through the center of the knife blade. For example: See picture below.
Angle abx would be 15 or 20 degrees and angle cbx would be 15 or 20 degrees depending whether you were talking about the primary or secondary bevels.
Angle abc would be 40 degrees for the primary and 30 degrees for the secondary bevel.
I didn't take the time to find a bisected double bevel and I don't have a photo editor. :)
I still don't see how you could grind that bevel edge that's only 1/32" wide using a Tormek.
I haven't really attempted one on the Tormek yet. One time I did increase the angle slightly and grind lightly. It's one one of those "intend to try" things. I regularly accomplish a double bevel with the DMT Aligner. So far, I haven't gotten away from using it.
Has anyone got the SMV-00 yet?
Not me....I freehand the small knives
I use the HK-50.
kb0rvo
The photos show exactly what I term as primary & back bevels the better quality Japanese knives - hardness around 60 > have a primary bevel of 15˚ on each face so 30˚ total and I usually thin them with a back bevel of 10˚ total 20˚ although it would be desirable to do an even finer back bevel angle . The one sided edges such as on Yanagibas are around 30˚for the primary cutting edge and then 20˚ for the back bevel . The other side of these knives are hollow ground and whilst sharpening it is necessary to remove the burr by laying this side on a flat stone (flat) and running it gentle over the stone to remove the burr.
I have been looking at making an HK-50 possible out of some aluminium plate depending on what I can find since I spent a long time putting a back bevel on a couple of Japanese knives that were well used and had not been sharpened at the right angles for a long time it took over an hour to put a the back bevel on them with an "Edge Pro" where as I am certain I could vastly reduce that time using a Tormec with an HK-50 set up.
I like to use the edge pro for the primary bevels and often run the blade on the leather wheel to finish then off .
Since I charge to sharpen I find in general sharpening knives on the Tormec can easily go wrong but if a knife needs a repair or real tapering the Tormec would be my choice. I suspect I will use the Tormec a lot more once I have fabricated a good HK-50.
I'm experimenting with different materials for making the HK-50. My latest concern is the scratches it makes on the sides of knives. This is not a concern for old paring knives but might be a concern for knives that have a polished finish.
I'm finding that varnished oak with a drop of motor oil as a lubricant is working well. Needs more testing, though.
I tried visiting my Tormek dealer while visiting my former area yesterday. No SVM-00 in stock yet. Nor is it listed in their online catalog. That surprises me, it is one of the largest hardware stores in the country.
Ken
I think the factory ran out of stock. Sharp Tools USA announced they were temporarily unavailable.
I just ordered one from Amazon.com, I'll have it tomorrow.
I've waited long enough for my local dealer to stock this jig. None yet. I checked on Amazon. $39.95 plus shipping through Advanced Machinery. I can see $32.00, even if they tack on shipping. That's what it sells for at Sharptools, which is now Advanced Machinery.
Sharptools only has payment via Google, at least online. I tried to order one, and could not get past the google account. Call me contrary, but I just want to order it from the dealer.
Advanced Machinery doesn't list the jig alone on their site. There is no shortage. The supply has been rerouted to the package deal with the T7.
This customer is not a happy camper. I have decided not to purchase the jig until the dealers get their acts together.
Ken
Dear dear....that's a pretty big measure of something not being right when probably Tormek's greatest fan isn't happy!
I relented. I just called the 800 number on the Sharptools site (and reached Advanced Machinery). The helpful rep took my order over the phone with no problems. My jig ($32.00 + shipping =$38.95) will be shipped today. I consider that very good service.
I still don't like the way the price was jacked up on Amazon (by the same dealer) or having to use Google check out if I had placed the order online.
I will post again after I have a chance to use the jig.
Ken