Gouge sharpening

[FiddleMkr]

I’m trying to find the best way to keep a gouge sharp; better said; I am trying to find the easiest way to resharpen a gouge after it dulls with use.  
     My way of sharpening is to use diamond plates, 300, 600, 1200, then either 4000 stone or leather and honing compound (or both). 
     Then to resharpen after the gouge gets dull with use, I use the leather (plus compound) but most often I have to go to the 1200 grit, then the leather to polish. What I would like is a one step rehoning, if I could find one. Maybe ceramic?   
        I could probably find the answer through experimentation but I was hoping that someone had found a one step process to resharpen their gouges and they wouldn’t mind sharing their experience. Thanks in advance. 

[Shunyata]

The abrasive paper systems with float glass are a very convenient way to touch up gouges.  A few squirts of water and quick passes with 5,000-15,000 grit papers has you razor sharp again.  1 minute at most.

I just leave a few glass strips with different grits and a spray bottle sitting out on my work table.

I prefer the 3M adhesive papers.  They are good for about a years worth of use before they need to be replaced.

[FiddleMkr]

2 hours ago, Shunyata said:

The abrasive paper systems with float glass are a very convenient way to touch up gouges.  A few squirts of water and quick passes with 5,000-15,000 grit papers has you razor sharp again.  1 minute at most.

I just leave a few glass strips with different grits and a spray bottle sitting out on my work table.

I prefer the 3M adhesive papers.  They are good for about a years worth of use before they need to be replaced.

by “float glass” do you mean just a flat piece of glass? That you adhere the abrasive paper to ?

edit: I looked up “float glass”. I hadn’t heard the term. (I wasn’t asking a stupid question (not intentionally)). 

Edited June 13, 2024 by FiddleMkr
Added paragraph

[Dennis J]

Using a 4000 stone followed by leather and honing compound is all that you need to refresh an edge. It might also be necessary to use a 4000 slipstone and leather on the incannel surface.

The 300 should only be used to form an initial bevel away from the cutting edge.

I just checked the bevel angle on this gouge. It is about 15 degrees. And taking the curvature into account its angle at the cutting edge is about 20 degrees or perhaps a little more.

If you don't grind gouge bevels at a low angle like this resharpening will be ineffective. Higher angles would require the whole bevel being ground back. In my experience Pfeil gouges tend to be a little soft producing large, flexible honing burrs which can be difficult to remove especially with acute cutting edges like these.

In the photos you can see how the incannel surface is slightly concave approaching the cutting edge so a fine slipstone works on the cutting edge only. Without that factor alone keeping gouges sharp can be problematic.

 

[LCF]

It would be helpful sometimes when these aspects of sharpening are being discussed if there was a simple sketch of the cross section included with the descriptions. Gets a bit confusing otherwise.

[FiddleMkr]

13 hours ago, Shunyata said:

The abrasive paper systems with float glass are a very convenient way to touch up gouges.  A few squirts of water and quick passes with 5,000-15,000 grit papers has you razor sharp again.  1 minute at most.

I just leave a few glass strips with different grits and a spray bottle sitting out on my work table.

I prefer the 3M adhesive papers.  They are good for about a years worth of use before they need to be replaced.

I found that there’s a sharpening “system” that you can buy using glass and abrasive paper. I didn’t know. Thanks.

[FiddleMkr]

7 hours ago, Dennis J said:

Using a 4000 stone followed by leather and honing compound is all that you need to refresh an edge. It might also be necessary to use a 4000 slipstone and leather on the incannel surface.

The 300 should only be used to form an initial bevel away from the cutting edge.

I just checked the bevel angle on this gouge. It is about 15 degrees. And taking the curvature into account its angle at the cutting edge is about 20 degrees or perhaps a little more.

If you don't grind gouge bevels at a low angle like this resharpening will be ineffective. Higher angles would require the whole bevel being ground back. In my experience Pfeil gouges tend to be a little soft producing large, flexible honing burrs which can be difficult to remove especially with acute cutting edges like these.

In the photos you can see how the incannel surface is slightly concave approaching the cutting edge so a fine slipstone works on the cutting edge only. Without that factor alone keeping gouges sharp can be problematic.

 

I used a the 4000 grit stone plus leather hone yesterday and it gets the job done. 
      

[JacksonMaberry]

Bevel geometry is a useful consideration, and should reflect the nature of the steel for best results. 

[Shunyata]

24 minutes ago, JacksonMaberry said:

Bevel geometry is a useful consideration, and should reflect the nature of the steel for best results. 

Amen to that!

[Dennis J]

Here is a rough drawing showing the basic measurements and geometry of two gouges.

The 15 degree bevel is not something I have not aimed for but it seems to be what works best. I'm a bit surprised that it is that low although with the slight rounding of the bevel it probably means a working edge close to 20 degrees.

The thickness of the blades for both gouges is about 3.2 , the bevel for the larger one is about 11 mm wide and the smaller one about 9 mm. That compares to a block plane blade of about 3.2 mm thick with a bevel about 6 mm wide having a cutting angle of about 25 deg. So these gouges are definitely sharpened at a very low angle, but they stand up very well. Whether that holds for other gouges out there I don't know. But I think that gouges sharpened at a higher angle would not work as well generally speaking.

Edited June 15, 2024 by Dennis J
addition

[FiddleMkr]

10 hours ago, JacksonMaberry said:

Bevel geometry is a useful consideration, and should reflect the nature of the steel for best results. 

Yes, I have a book on sharpening that solved a “dull” gouge problem, ie edge geometry. In fact I made one of my gouges the “ideal” geometry, or close to that, and it almost cuts too well. (I had to guess at many of the angles and I’m sure it is not actually the ideal or it would be easier to control the cut.) 

[Shunyata]

2 hours ago, FiddleMkr said:

Yes, I have a book on sharpening that solved a “dull” gouge problem, ie edge geometry.

What is the book?

[FiddleMkr]

2 hours ago, Shunyata said:

What is the book?

The complete guide to sharpening, by Leonard Lee.

 

[Dennis J]

One thing I can say is that I have never read anything about gouge sharpening. And I haven't taken much notice of videos online. I'm not saying that there isn't some good advice out there, but I haven't seen much.

And one thing that I think is essential as far as sharpening gouges, apart from honing angles is concerned, is the use of slipstones. If the incannel surface behind the cutting edge is slightly hollow a slipstone will work very well. In the photo the slipstone is only making contact with the cutting edge and further up towards the handle. So to work properly a slipstone needs to be resting like this or at the least on a flat surface.

 

[JacksonMaberry]

I also find slip stones indispensable. I have two, 1k and 3k. I use a bit of dowel with green compound on it as my final "slipstone". 

For the outcannel, I use 1k, 6k, and 10k stones. I finish ( and refresh) with green compound on MDF. For most tools I prefer that hard strop to leather. 

 

But, this is just what I do. Lots of ways to skin this cat. 

[LCF]

19 minutes ago, JacksonMaberry said:

I also find slip stones indispensable. I have two, 1k and 3k. I use a bit of dowel with green compound on it as my final "slipstone". 

For the outcannel, I use 1k, 6k, and 10k stones. I finish ( and refresh) with green compound on MDF. For most tools I prefer that hard strop to leather. 

 

But, this is just what I do. Lots of ways to skin this cat. 

MDF is very useful like that. I also have a very hard Arkansas slipstone, grit unknown, which I use on gouges. 

Arkansas stones seem to be in short supply nowadays.

[JacksonMaberry]

3 minutes ago, LCF said:

MDF is very useful like that. I also have a very hard Arkansas slipstone, grit unknown, which I use on gouges. 

Arkansas stones seem to be in short supply nowadays.

The nicest natural stone I ever used was an Arkansas a friend had, alongside a Belgian coticule. I haven't used a really fine Japanese natural stone, but I'd like to if I win the lottery. I'm not surprised, I suppose, to hear that they're over mined. 

I actually really like the synthetic Japanese water stones designed for hispeed steels. They cut (and also wear) very quickly. I've used the same set for the last 7 years, and my 10k finally cracked. I'm using the bits but I really ought to replace it. I can get a fine edge going from the 6k to the MDF strop, but I can absolutely feel the difference when using the 10k between them. You can see it too, under magnification. 

The sharpest blades I have are all old low alloy carbon, but they are not the toughest. Horses for courses. 

[Dennis J]

The gouges that I have date back to the time when British woodworkers and furniture makers carved their way through huge amounts of African mahogany and other hardwoods making Victorian era furniture. They used leather strops and slipstones regularly before rehoning their tools. But the gouges themselves had the geometry and quality that made that sort of process possible.

I should add that only use the 4000 slipstone occasionally along with a cotton mop charged with rouge and chrome oxide to refresh an edge. When rehoning the whole bevel with coarser stones I might use a 1000 slipstone followed by the 4000 followed by the buff.

[JacksonMaberry]

4 minutes ago, Dennis J said:

The gouges that I have date back to the time when British woodworkers and furniture makers carved their way through huge amounts of African mahogany and other hardwoods making Victorian era furniture. They used leather strops and slipstones regularly before rehoning their tools. But the gouges themselves had the geometry and quality that made that sort of process possible.

Yep, it really comes down to steel quality (including temper/heat treat) bevel geometry (suiting the qualities of the steel and the material to be worked), and technique (sharpening/honing and actual use of the tool).

It ain't rocket surgery, it just takes time to develop the skill. 

[LCF]

1 hour ago, JacksonMaberry said:

The nicest natural stone I ever used was an Arkansas a friend had, alongside a Belgian coticule. I haven't used a really fine Japanese natural stone, but I'd like to if I win the lottery. I'm not surprised, I suppose, to hear that they're over mined. 

I actually really like the synthetic Japanese water stones designed for hispeed steels. They cut (and also wear) very quickly. I've used the same set for the last 7 years, and my 10k finally cracked. I'm using the bits but I really ought to replace it. I can get a fine edge going from the 6k to the MDF strop, but I can absolutely feel the difference when using the 10k between them. You can see it too, under magnification. 

The sharpest blades I have are all old low alloy carbon, but they are not the toughest. Horses for courses. 

My flat Arkansas stone is in the same state as your 10k but I still like to use the bits.

[FiddleMkr]

14 hours ago, Dennis J said:

One thing I can say is that I have never read anything about gouge sharpening. And I haven't taken much notice of videos online. I'm not saying that there isn't some good advice out there, but I haven't seen much.

And one thing that I think is essential as far as sharpening gouges, apart from honing angles is concerned, is the use of slipstones. If the incannel surface behind the cutting edge is slightly hollow a slipstone will work very well. In the photo the slipstone is only making contact with the cutting edge and further up towards the handle. So to work properly a slipstone needs to be resting like this or at the least on a flat surface.

 

Is the tool in the first photo a gage or a stone (that grinds a hollow into the surfaces)?

[LCF]

14 minutes ago, FiddleMkr said:

Is the tool in the first photo a gage or a stone (that grinds a hollow into the surfaces)?

Veritas bevel gauge.

[FiddleMkr]

17 hours ago, Dennis J said:

And one thing that I think is essential as far as sharpening gouges, apart from honing angles is concerned, is the use of slipstones. If the incannel surface behind the cutting edge is slightly hollow a slipstone will work very well. 

 

The gouges that I have are flat behind the incannel edge, at least when new, but then become slightly humped after sharpening. I can think of a way to put a hollow behind the edge, however crude, using a dremel tool, but what technique do you use to create a hollow behind the incannel edge?

Edited June 16, 2024 by FiddleMkr
Rewording

[FiddleMkr]

22 hours ago, Dennis J said:

One thing I can say is that I have never read anything about gouge sharpening.

      What I found to be the most helpful in the book concerns the geometry of the bevels. 
      I can’t explain well what the author does, but the general idea is to look at the gouge geometry with respect to the wood. So you put the ideal geometry at the center and at the sides, then blend the two together. What you are left with is a gradually changing bevel from outside to inside, where in the center all the bevel is on the outside, and on each side all the bevel is on the inside. And you keep the included angle the same, say 20 degrees. 
      What I particularly like about what you added is the hollow behind the edge. I can see how this is important for both sides of the bevel. For the outside I can see that an easy way to create this hollow would include the edge of a grinding wheel on a bench grinder.  Do you have a preference for the inside hollow? The only idea I have is to use a dremel tool, but it would be hard to get much precision this way.  Do you have a better way?
 

Edited June 16, 2024 by FiddleMkr
Reworded

[Dennis J]

If I understand what your book suggests the gouge is bevelled on the incannel surface at the sides or wings of the gouge. Something like that might be possible but it sounds awfully complicated and I can't imagine what purpose it would serve.

Using a mallet I can hold a gouge sharpened properly at a fairly low angle and drive it into a piece of wood and it can take a full depth cut and then climb out of the cut just about automatically. If I wish to continue the scoop I can just raise the handle a little.

The hollow behind the cutting edge I'm talking about is a feature of the old gouges I have. It's only slight, no more than about 1 mm, but that's how they were forged and shaped. However a lot of these old gouges are well worn and that hollow has been lost. I have been able to deal with that on a few which had rounded over incannel edges or rust pitting using a Dremel and flap wheels but it is a very slow process on this sort of hardened steel. Larger grinders with a longer reach and soft grinding heads would be ideal but I don't have one. If you can lay a straight edge on the incannel surface you can clearly see whether a slipstone will make contact with the cutting edge. That surface doesn't have to be hollow but it does need to be at least flat. Tilting the slipstone to make contact with the edge doesn't work very well.

Nearly all of my chisels and gouges are old to very old but all of them are in perfect working order, but some of them have required a bit of work to get them that way. The only modern chisels and gouges I've had are Pfeils which I sold. I don't know if the gouges had any hollowing but I did manage to sharpen them alright. I would say most modern ones have flat incannel surfaces, which is ok, but the hollowing makes deburring or smoothing much more precise.