Sharpening Record No 4 - Silicon paper

[ByronBlack]

Jacob, any chance of a video of you demonstrating this?

 

[Anonymous]

Jacob, any chance of a video of you demonstrating this?

Byron, can't do it haven't got the kit. My kids have though, I'll try and get them on the job.

cheers
Jacob

 

[Benchwayze]

Right folks,

All I can go on is what I was taught, and what has always served me.

In the 1950's I got a 'lecture' from my Woodwork teacher, until I could hone freehand and maintain a flat bevel. It isn't easy.
When I asked why the bevel should be flat, said teacher gave me the 'ship's prow' analogy. he explained that a flat bevelled chisel cuts better than a rounded bevel, because in effect, both sides of the chisel edge can CUT rather than BULLNOSE through the fibres.

Now that I am my own man I still prefer a flat bevel.

As to my test, the fact still remains, both chisels had the same test. The rounded part of the curved-bevel chisel showed crushing of the fibres. The other showed a cutting action on both sides.

Finally, so far, no one but my Woodwork Teacher and my first foreman ever sent back any of my work.

Fin... And all the best on this one!

John

 

[Benchwayze]

I do not know about you, but I get a mirror finish, I love the way my bevels look, and they do shave the hair off my body. I have no idea how thick the shavings are.

I am assuming you mean shaving off the hairs on your wrist/forearm Javali!!!!

I once wondered if I could shave with a plane iron, but I decided it would be a waste of a good edge! In any case, I can cut myself with 'safety' razor blades! reckon I'll grow a beard. :shock: :shock:

Happy Woodworking and be lucky
John

 

[Anonymous]

I can't see any logic in the ships bow analogy. Bows tend to be rounded anyway, not to mention the bulbous bottle thing which most ships have just below the waterline at the pointy end!.
Anyway it's not about pseudo scientific tests it's about what works in practice, and my re-discovered rounded bevel technique works brilliantly without a doubt, which is why I keep blagging on about it, I'm not just trolling you know. :roll:
I say "re-discovered" cos I'm sure this was how it was always done before people started thinking too hard about it.
It's a bit like riding a bike - nobody tells you how to do it and infact many cyclists haven't the foggiest idea what keeps them upright, so couldn't tell you anyway. So they added stabilisers - very similar to honing jigs; no use at all :lol:

cheers
Jacob

 

[bugbear]

A rounded bevel means starting off cautiously at 30 deg, but after a few mm then dipping slightly at which point you throw caution to the wind and can press down hard and stab the chisel forward quickly and energetically.

... and achieve nothing except altering the relief angle for the next sharpening. What a waste of time!

I see no benefit in working at an angle below 30 for any abrasive other that the first (coarsest).

No "double beveller" would dream of wasting time working the primary bevel with a fine grit - this seem self-evident. Perhaps the rounded bevel obscures this truth.

BugBear

 

[Anonymous]

A rounded bevel means starting off cautiously at 30 deg, but after a few mm then dipping slightly at which point you throw caution to the wind and can press down hard and stab the chisel forward quickly and energetically.

... and achieve nothing except altering the relief angle for the next sharpening. What a waste of time!

Bugbear I think you've got it "altering the relief angle for the next sharpening". A waste of time yes - until you come to "the next sharpening". And done in one step instead of two. Is also "altering the relief angle for the next" pass during the current sharpening, which is what speeds things up so much.
So it's win win - you have only to look a few seconds ahead to see what the gain is.

I see no benefit in working at an angle below 30 for any abrasive other that the first (coarsest).

No "double beveller" would dream of wasting time working the primary bevel with a fine grit - this seem self-evident.

It is self evident I agree, if you are a "double beveller" that is. If on the other hand you are a "rounded single beveller" it saves time and is easier. Bigger blades or chisels still means moving up a grade or two however, but grinding also a rounded bevel ('cos it saves time and is quicker).

Perhaps the rounded bevel obscures this truth.

BugBear

Err, dunno, praps :lol:

cheers
Jacob

 

[bugbear]

A rounded bevel means starting off cautiously at 30 deg, but after a few mm then dipping slightly at which point you throw caution to the wind and can press down hard and stab the chisel forward quickly and energetically.

... and achieve nothing except altering the relief angle for the next sharpening. What a waste of time!

Bugbear I think you've got it "altering the relief angle for the next sharpening". A waste of time yes - until you come to "the next sharpening". And done in one step instead of two. Is also "altering the relief angle for the next" pass during the current sharpening, which is what speeds things up so much.
So it's win win - you have only to look a few seconds ahead to see what the gain is.

There's clearly no point dipping/rounding/dubbing below 30 degrees when using an abrasive too fine (and thus slow) to create any useful relief. Any such strokes are simply wasted, regardless of "vigour".

Conversely, any stray steep strokes when using the coarse abrasive will remove far more material than is desirable from the precious tip.

If care is taken that strokes when using the coarse abrasive are kept in a "lowish" range, and strokes when using finer abrasives are kept in a "highish range", all will be well.

Of course, at this point, we're simply talking about a varient of good ol' double bevelled sharpening.

BugBear

 

[javali]

As to my test, the fact still remains, both chisels had the same test. The rounded part of the curved-bevel chisel showed crushing of the fibres. The other showed a cutting action on both sides.

OK, so I had my test. Sharpened my Stanley #3 blade with a round bevel. put it in, tuned, and it takes full width gossamer shavings. Put the blade in the veritas Mk II jig, ground a flat bevel, back to the plane, and however I set the blade, it skids over the timber. No shavings at all.

For the record, the grinding angle was 50 degrees, and we all know that it is not the best bevel angle for a Stanley #3, but the fact still remains, both planes had the same test. The round bevel takes fine shavings, while the flat bevel does not take any shavings.

So, do we agree that flat bevel is better for chisels while round bevel is essential for planes? :roll:

Conversely, any stray steep strokes when using the coarse abrasive will remove far more material than is desirable from the precious tip.

Just out of curiousity, how many of your blades have reached the end of their useful life in the past 10 years? How many times a week do you sharpen a blade?

 

[bugbear]

For the record, the grinding angle was 50 degrees, and we all know that it is not the best bevel angle for a Stanley #3

Assuming we're talking about a bevel down, 45 degree frog sort of #3 (i.e. a normal one) a 50 degree tip bevel will indeed skid, no matter how it was created. This is because part of the blade behind the edge is lower than the edge, and will hit the wood first. (draw a diagram).

So, do we agree that flat bevel is better for chisels while round bevel is essential for planes? :roll:

Actually, it's about the difference between bevel down and bevel up. Chisels are normally used bevel up, whilst plane quite commonly come in both flavours.

Conversely, any stray steep strokes when using the coarse abrasive will remove far more material than is desirable from the precious tip.

Just out of curiousity, how many of your blades have reached the end of their useful life in the past 10 years? How many times a week do you sharpen a blade?

My concern is not "using up" the blade.

The end of the chisel is kept "narrow", so that even fine abrasives can work quikly and effectively. This narrowness means that a coarse abrasive will remove metal at a **** of a rate.

This consequently means that to keep the ratio consistent (double bevel) or the shape consistent (rounded bevel) a good deal of metal needs to be removed from the "primary"/"top part".

But in double bevel sharpening, either hand or jig, one NEVER (deliberately...) uses the coarse abrasive on the tip, whereas (as I understand it) Jacob's approach involves deliberately doing exactly that.

With a jig, of course, such a separation is absolute.

Indeed, in normal "touch up" sharpening, I only use the 30 degree angle (and comparitively fine abrasives).

When the secondary bevel becomes a little large (this is rarer event), I use a coarser abrasive, and a lower angle (normally 5 degrees lower than my desired secondary). Sometime, I do this freehand, sometime with a jig. The odd stray stroke higher than my target does no damage, as long as my error is less than 5 degrees.

I never use a fine abrasive on the primary bevel (no point), and I never use a coarse abrasive on the secondary (too fierce).

The former point is not critical, the latter is more important.

BugBear

 

[Anonymous]

A rounded bevel means starting off cautiously at 30 deg, but after a few mm then dipping slightly at which point you throw caution to the wind and can press down hard and stab the chisel forward quickly and energetically.

... and achieve nothing except altering the relief angle for the next sharpening. What a waste of time!

Bugbear I think you've got it "altering the relief angle for the next sharpening". A waste of time yes - until you come to "the next sharpening". And done in one step instead of two. Is also "altering the relief angle for the next" pass during the current sharpening, which is what speeds things up so much.
So it's win win - you have only to look a few seconds ahead to see what the gain is.

There's clearly no point dipping/rounding/dubbing below 30 degrees when using an abrasive too fine (and thus slow) to create any useful relief. Any such strokes are simply wasted, regardless of "vigour".

Strewth not sure if I can keep this up :roll:
What you've just written is of course true - but if the grit is so fine that it won't back off the bevel, then it will be too fine to hone the flat part of the bevel.

Conversely, any stray steep strokes when using the coarse abrasive will remove far more material than is desirable from the precious tip.

If care is taken that strokes when using the coarse abrasive are kept in a "lowish" range, and strokes when using finer abrasives are kept in a "highish range", all will be well.

Of course, at this point, we're simply talking about a varient of good ol' double bevelled sharpening.

BugBear

Well yes - as I've pointed out - one grit only will work for smaller edges, bigger ones may need 2 grits. So it is a variant if you like. But it works a lot better because it's quicker and easier.
It's no good coming up with arguments about why it won't work when it self evidently does work just as I've described, for me at least. I suggest you stop worrying about it - you do it your way and I'll do it mine

cheers
Jacob
PS re javali's question about usage. I've been a fairly busy woodworker since I bought my first chisels and planes in about 1975. In that time I haven't worn out many blades at all except a block plane and a couple of chisels. The chisels went more through damage than normal use - having to do something desperate on site etc.
You'd have to do a phenomenal amount of work to wear them out - or more likely a phenomenally excessive amount of sharpening - quite probable if you use a tormek or whatever :lol:
PPS

But in double bevel sharpening, either hand or jig, one NEVER (deliberately...) uses the coarse abrasive on the tip, whereas (as I understand it) Jacob's approach involves deliberately doing exactly that.

Bugbear - I thought you had carefully read every word I have written :shock:
No I don't use a coarse abrasive on the tip. If a fine stone is too slow I use a coarser stone but starting at 25 deg but still rounding the bevel. Although if in a hurry I might use the next to finest as the finishing grit on a wide plane blade.

 

[bugbear]

It's no good coming up with arguments about why it won't work when it self evidently does work just as I've described, for me at least. I suggest you stop worrying about it - you do it your way and I'll do it mine

Interesting approach to a discussion forum, but since you want to stop...

BugBear

 

[Anonymous]

It's no good coming up with arguments about why it won't work when it self evidently does work just as I've described, for me at least. I suggest you stop worrying about it - you do it your way and I'll do it mine

Interesting approach to a discussion forum, but since you want to stop...

BugBear

Well I had to be carried off screaming from here to the sound of slow hand clapping, and I wrote it up here (needs up dating I see). Not sure if I've anything to add.
Anyway - have a go then you might see what I'm on about!

cheers
Jacob

 

[javali]

For the record, the grinding angle was 50 degrees, and we all know that it is not the best bevel angle for a Stanley #3

Assuming we're talking about a bevel down, 45 degree frog sort of #3 (i.e. a normal one) a 50 degree tip bevel will indeed skid, no matter how it was created. This is because part of the blade behind the edge is lower than the edge, and will hit the wood first. (draw a diagram).

You are absolutely right. We also know that a chisel honed at 40 degrees tends to crush wood fibers more than a chisel honed at 30 degrees. If John is allowed to ignore the honing angle, I am taking the same liberties.

My concern is not "using up" the blade.

I never use a fine abrasive on the primary bevel (no point), and I never use a coarse abrasive on the secondary (too fierce).

The former point is not critical, the latter is more important.

Except for possibly "using up" the blade faster, why is it more important?


BTW, guys, if I read Google maps correctly, you are only about 3 hours drive away from each other. Why don't you meet on a fine weekend to have a serious evaluation of the round bevel method? Not to convince anyone to switch to round bevel - just to establish its validity, and to be able to have a discussion based more on observation than on assumptions. I would be happy to join if someone covers the airfare.