Convexed Dovo Hone

[lightfoot]

Check out these fascinating videos Jarrod from TSS posted a while back. They demonstrate the use and purpose of the arched hones that Dovo uses at the facory

 

[SliceOfLife]

The high point that he describes is how a lot of vintage razor hones are found. Many Thuringian, cotis, and almost every single Pierre DSO I've bought came this way.

I always assumed it was a result of how they were leveled by the mines and just meant the hone had seen little use. Interesting that he suggests that they might have developed the high centers due to use (honing on the edge of the stone inward).

 

[lightfoot]

The high point that he describes is how a lot of vintage razor hones are found. Many Thuringian, cotis, and almost every single Pierre DSO I've bought came this way.

I always assumed it was a result of how they were leveled by the mines and just meant the hone had seen little use. Interesting that he suggests that they might have developed the high centers due to use (honing on the edge of the stone inward).

Slice these videos are interesting indeed! What's fascinating to me is that Dovo is required to prepare there hones in this manner per the trade guild guidelines according to the 2nd video...

 

[bluesman 7]

A convex hone and a straight edge would have the same advantage as honing a smile on a flat hone, which is that you are not contacting the whole edge at the same time so every part of the edge gets individual attention with regard to pressure.

 

[eKretz]

Yep, I noticed the shape of their hone from the very first time I saw the Dovo factory video on How It's Made. It's almost certainly trade guild spec'ed for a reason. This way they get a good apex all the way down the razor's edge as fast as possible. No worries about whether a slight warp or similar issue will make a blade take a long time to hone. Time is money in a manufacturing setting. Personally I'd rather have a flat hone and a smiling blade - YMMV.

 

[Steve56]

I'm with Eric and bluesman7.

Furthermore I'll throw the BS flag. A convex hone is functionally a narrow hone that can more effectively hone warped or unevenly ground razors. Having a convex hone on a razor production line means they haven't mastered their craft; it isn't something to be admired. But I do admire marketing a liability as a plus! I understand they're doing the best they can with tremendous demand and a long learning curve for the grinders, but a warped or misground razor is just that and there's not much else to be said.

I don't have a honing problem with warped or misground razors, I have narrow hones for just that reason. I do have a problem with trying to pass off warped or poorly ground razors at full price and touting the virtues of a convex hone or that warped or misground razors are the price consumers must pay for some other quality.

If you talk to an engineer or designer at any of the major remaining manufacturers, I would bet money that none of the engineers intend the razor to be warped or misground, those are not design criteria.

Cheers, Steve

 

[lightfoot]

To bluesman, Steve, &/or Eric,
Would any of you be willing to post a video on this thread at some point demonstrating the use of a narrow hone on a tricky razor? I've been on the forum for a while now but I haven't seen anyone post such a video and I think it might be a good resource for others to see. I film all of my videos on my phone with good results as long as I have good lighting...

 

[bluesman 7]

I rarely use a narrow hone. When I do it is a Chosera 1k on it's side and I'm doing it to concentrate on one area of the blade without taking material from the rest of the blade. Said another way, 'when the problem is an in board area of the blade and I want to avoid honing the toe'. This is all prior to the bevel being completely set. Once I've brought the problem area up I go back to the flat face of the hone and finish setting the bevel. It's all wider hones from there.

 

[Steve56]

I don't have videos but the idea is pretty simple. This method is for honing a frown, not removing it.

The narrow hone is usually used with a sliding stroke so the hone can ride into the frown, just like the technique that likely created it.

You can also use back and forth strokes on the corner of a hone to ride into the hone if you don't have a narrow hone or one thick enough to use the side.

Cheers, Steve

 

[bluesman 7]

@Steve56. That corner idea is good. I had never thought of that.

 

[Steve56]

It's a good solution to an unpleasant problem lol

Cheers, Steve

 

[lightfoot]

I may catch heck for this but I've wanted to get one of Dan's arkie files just to play with. I was looking at one of their round 6x3/8" hones...

 

[eKretz]

Corners and edges can be quite handy at times. A badly warped razor can look quite rough if it's honed to complete cleanup on a wide flat stone in the conventional manner. Using a narrow stone or Steve's corner trick they can be brought to a nice shaving edge with much better aesthetics.

The fully round hone might be difficult to use as it will be very unstable and possibly hard to safely hold while honing a razor unless brought to bear against the razor as a file might be. Personally I've always found this more difficult than bringing the razor to the stone. May be just force of habit though.

 

[Jarrod]

since 2016, gone are naturals @ Dovo; they just can't get big and pure enough so they switched over to synthetics from JP, which will make a point to document soon enough. That footage is six yrs old.

Preparation to the sloped way still done by hand, mostly by just using a blade where and for how long, I think some use of naguras to wear down.

I'd like a 12" circular coticule on a turntable with ~1.5mm rise to center and just move the blade radially to center, spine hone, repeat, switch sides, repeat...I bet such a stone can be had in fine alum oxide base.

Honing on the rounded stone takes practice. It is very quick to correct bevel plane widths.

 

[eKretz]

∆∆That would be awesome! Many of us had the same thought about a circular black Ark that was posted in one of the Arkie threads.

 

[lightfoot]

I don't have videos but the idea is pretty simple. This method is for honing a frown, not removing it.

The narrow hone is usually used with a sliding stroke so the hone can ride into the frown, just like the technique that likely created it.

You can also use back and forth strokes on the corner of a hone to ride into the hone if you don't have a narrow hone or one thick enough to use the side.

Cheers, Steve

View attachment 786184 View attachment 786185

Thanks for the pics Steve. Deffinately some crafty hone work. Honing difficult blades in a manner that works in harmony with a razors geometry rather than against it is still kind of like honing wizardry to me...

 

[Steve56]

Thanks for the pics Steve. Deffinately some crafty hone work. Honing difficult blades in a manner that works in harmony with a razors geometry rather than against it is still kind of like honing wizardry to me...

It isn't really. If you have a razor that has wonky geometry because of poor honing practices over decades, you just hone it the same way that caused the problem in the first place. I mean someone was honing and shaving with it to cause the frown/smile/upsweep... Just use the corner or edge on frowns or overground razors if you don't have a narrow hone.

You see a lot of frowns in older European razors because the hones were narrower and many people did not use the hones properly. A 3" wide Thuringian or coticule was pretty much non-existent, even slate razor hones were narrower though they paved roads and built walls with the same slate. I've never understood that. So you just hone it the same (improper really) way they did.

Now those 'U' shaped bevels from pasted strops, those have to go.

Cheers, Steve

 

[Jarrod]

update; revisited w/ Dovo in Solingen May 9. They still use only convexed bench stones.

But no more natural stones since early 2015 or so (original video was from 2011 when they still used coticules & Arkansas stones).

Also visited with 3 other Solingen straight razor productions; not all are as transparent (in wanting their internal productions showcased via YouTube videos), there's always been a vibe among older master grinders to wish to keep their trade secrets as close to the chest as possible. But all seem in agreement on the convexed bench stones issue, for that is what all used exclusively, including a tiny manufacturer in no hurry at a ll who makes under 1000 pcs per yr...there wasn't a level bench stone among them, and they're seemingly really good at getting that rise % to be miniscule, consistent, and slightly spherical rather than 'ridgeline down center line' style. One of the makers primarily uses machinery produced in 1919!

 

[lightfoot]

update; revisited w/ Dovo in Solingen May 9. They still use only convexed bench stones.

But no more natural stones since early 2015 or so (original video was from 2011 when they still used coticules & Arkansas stones).

Also visited with 3 other Solingen straight razor productions; not all are as transparent (in wanting their internal productions showcased via YouTube videos), there's always been a vibe among older master grinders to wish to keep their trade secrets as close to the chest as possible. But all seem in agreement on the convexed bench stones issue, for that is what all used exclusively, including a tiny manufacturer in no hurry at a ll who makes under 1000 pcs per yr...there wasn't a level bench stone among them, and they're seemingly really good at getting that rise % to be miniscule, consistent, and slightly spherical rather than 'ridgeline down center line' style. One of the makers primarily uses machinery produced in 1919!

Thanks a lot Jarrod. I've been curious about your most recent trip. Did you get any footage?

 

[Jarrod]

I've been curious about your most recent trip. Did you get any footage?

Yes, have posted numerous videos the past wk from Solingen and Isle of Man (@ that really big video-specific site), many more to go!