How do you sharpen an asymmetrical grind deep fluted gouge?

[Jake Gevorgian]

I do it manually. Is there a jig that you use to sharpen it?

 

[john lucas]

Do you mean one wing longer than the other. It's easy to do with the Oneway Wolverine or any other jig similar. Just grind longer and move the gouge to grind as far back as you wish. Many people do this accidentally by simply staying too long on one side.

 

[Jake Gevorgian]

Do you mean one wing longer than the other. It's easy to do with the Oneway Wolverine or any other jig similar. Just grind longer and move the gouge to grind as far back as you wish. Many people do this accidentally by simply staying too long on one side.

I mean 60 degrees on one side and 45 on the other (somewhere around these angles, not too precise)

 

[john lucas]

So you mean you want a 60 degree cutting angle on one of the wings and a 45 degree cutting angle on the other wing. To achieve that with something like the Wolverine jig the bottom of the jig would have to either rock or move up or down to change the angle as the tool is rotated from one wing to another. Much easier to just grind free hand on something like that.

 

[robo hippy]

Yea, like John said, free hand would work better. You just roll it more over on one side than the other.

Just out of curiosity, why do you want the different angles?

robo hippy

 

[john lucas]

I should have asked that also. I'm dying to know. I do have a gouge that has a long wing that I use to use primarily for pull cuts when doing my mirrors. I don't use it much anymore.

 

[Jake Gevorgian]

Alright, I made a video of how I sharpen the asymmetric bowl gouge. The usage is great when I make hollow forms (or a bowl that has a smaller opening, larger curve as it goes in and smaller base.) The different angles help me prevent catch when I'm doing the hollow forms initial cuts, and then help me throughout the bottom---that is to say, an Elsworth grind on one side and a traditional grind on the other.
Anyway, the tool has some accent (just like I do, after using three different languages daily) so that means it takes some time to get used to it.

Here is the video link http://www.youtube.com/watch?v=ChHFUBE55nM

 

[john lucas]

Thanks for posting the video. You are getting your catches while doing the inside because you don't have the handle far enough away from you. This means you don't have the bevel pointing in the direction you intend to go. consequently when you touch the wood it tries to skip on you. John Jordan once told me, start the cut gently. If your at the wrong angle it will be rejected gently. Start it rough and it rejects it rough. What you want to do is aim the bevel in the direction you want to go. This often means moving the handle further out than you think. Then start the cut gently. Once it starts you have a small shoulder for the bevel to ride on and the cut will proceed nicely.
Then angle you grind the right side doesn't have anything to do with why the tool is catching. A lot of it is because you are forcing the cut. Relax, slow down, let the tool do the cutting. With a lighter grip you can better feel the bevel on the wood. We are all starting to use the term gliding the bevel or guiding the bevel rather than riding. Riding the bevel implies that you push against it . In reality you steer the bevel like using the rudder of a boat and the cutting edge will move in the direction you want to go.
I'd like to hear some discussion on way you are sharpening from other turners. Using the soft portion of the belt rather than the platten area produces a rounded bevel. There are different feelings on this. Johannes Michelson's bevel seems to be rounded as well as Eli Avisera's skew. I've been playing with it a little and the verdict is still out for me. I find it harder find the bevel when rolling beads but maybe a little more forgiving for starting a cut but really don't have enough experience with it yet to have a valid opinion.
You seem to be taking way too much time to sharpen. Watch for sparks to come over the edge and then stop. Repeated passes only remove more metal, they don't make it sharper unless of course you aren't getting the grind all the way to the tip. I know that takes time to learn. I ground away my first tool fairly quickly.
I don't see a reason for your grind in the way that you turn. An Ellsworth grind with his jig or the standard grind straight off the Oneway Wolverine should do you fine. Your grind will work. I use gouges with both grinds.

 

[John Lawson]

Jake, I've little experience turning bowls, but I see a pattern in the way you present the tool when you're getting catches. It looks to me like you begin the cut with the flute at 1:00 o'clock and the tool skates off to the left. Then you correct the flute to 2:30-3:00 o'clock and it proceeds OK. The experienced bowl turners need to validate the significance of my observation, but that happens over and over in your video.

 

[odie]

Jake.......

You look to have spent a great deal of effort perfecting your double bevel grind.........but, it's my opinion that your long edge on the left side of the flute is your problem. I haven't used your progressive bevel grind on the internal shape of a bowl, so you can take my thoughts for what they're worth. It does look like the shape itself would be prone to catching with the way you are presenting it to the wood. There is very little positive control on the left side of the flute, but this gradually gets better as the tool progresses closer to the center where it levels out.

I am mostly using a standard bowl grind done at various bevel angles. This is done with the Wolverine using the V arm. Certainly my grind, and style is completely different than yours. Most of my internal cuts are near the tip and slightly to the right side of the flute. A long sharpened edge is not needed here in order to present the most useful cutting edge to the wood.

ooc

 

[MichaelMouse]

Interesting to watch. You need to spend more time using the nose of the gouge. If you lay the bottom of the flute parallel to the curve of the piece, you can stop those big wood-wasting kick-outs when hollowing. I use a plunge and roll technique for hogging, personally. Gouge is ground more or less symmetrical, because I, too, freehand on a grinder.

Hollowing sequence. http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=HollowTwo001.mp4 The pillar is left in for remount of the dry piece after the wood cures. Shavings, not chips are a good thing. You get chips because of the high pitch angles you use. If you lower the pitch for broad, not deep cutting, your control and surface would benefit. You can get a good idea of my flute direction by watching the shavings eject. The run around the flute and depart at about 90 degrees to the nose.

Here's seasoned wood with a nice, controlled entry. First is to take energy away from the turning by slowing the lathe down, second is to enter as narrow as possible, under control. http://s35.photobucket.com/albums/d160/GoodOnesGone/?action=view&current=Inside.mp4 Second sequence is back to the finishing gouge.


I finish with a completely different gouge. It's all nose. http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=CherryPeelIn.mp4 Even thin shavings on dry wood often hold together across the endgrain, because there's so little stress when you slice.

I use a gouge ground similarly to your left side for hollowing endgrain, but it's a shallow, "detail" gouge. http://i35.photobucket.com/albums/d160/GoodOnesGone/a63b77ab.jpg

It shaves the interior smoothly and ejects the shavings down the flute. Sure beats scraping, hosing and maybe jamming on the dust! http://i35.photobucket.com/albums/d160/GoodOnesGone/725a28f2.jpg

 

[robo hippy]

If the flutes are too up and down, the wings are more prone to catching. I have my gouge rolled over between 45 and 90 degrees all the time. As John said, moving the handle more away from you will help keep the skipping to a minimum.

I have heard of and seen the grind you use, but can't see that it has any advantages. I only have one swept back grind gouge, the rest are more of a fingernail grind. I use scrapers for roughing.

robo hippy

 

[Jake Gevorgian]

Thanks for posting the video. You are getting your catches while doing the inside because you don't have the handle far enough away from you. This means you don't have the bevel pointing in the direction you intend to go. consequently when you touch the wood it tries to skip on you. John Jordan once told me, start the cut gently. If your at the wrong angle it will be rejected gently. Start it rough and it rejects it rough. What you want to do is aim the bevel in the direction you want to go. This often means moving the handle further out than you think. Then start the cut gently. Once it starts you have a small shoulder for the bevel to ride on and the cut will proceed nicely.
Then angle you grind the right side doesn't have anything to do with why the tool is catching. A lot of it is because you are forcing the cut. Relax, slow down, let the tool do the cutting. With a lighter grip you can better feel the bevel on the wood. We are all starting to use the term gliding the bevel or guiding the bevel rather than riding. Riding the bevel implies that you push against it . In reality you steer the bevel like using the rudder of a boat and the cutting edge will move in the direction you want to go.
I'd like to hear some discussion on way you are sharpening from other turners. Using the soft portion of the belt rather than the platten area produces a rounded bevel. There are different feelings on this. Johannes Michelson's bevel seems to be rounded as well as Eli Avisera's skew. I've been playing with it a little and the verdict is still out for me. I find it harder find the bevel when rolling beads but maybe a little more forgiving for starting a cut but really don't have enough experience with it yet to have a valid opinion.
You seem to be taking way too much time to sharpen. Watch for sparks to come over the edge and then stop. Repeated passes only remove more metal, they don't make it sharper unless of course you aren't getting the grind all the way to the tip. I know that takes time to learn. I ground away my first tool fairly quickly.
I don't see a reason for your grind in the way that you turn. An Ellsworth grind with his jig or the standard grind straight off the Oneway Wolverine should do you fine. Your grind will work. I use gouges with both grinds.

Thanks John, as you saw in my video I was very unprepared for the video. First I did a quick run, then stopped the sander, then got a metal file to make a damage "as if" I'm trying to say, hey, I did it. Then, I wanted to make it in a way, so that I don't shut the camera off, and I position it to records the motion on the lathe and to show that that's the gouge I'm using... Anyway...this video is a total failure if you were to ask me about the quality. I think that if I have done a better preparation and directed the video correctly, you wouldn't see me so nervous -- I was trying not to block the camera view and that is when I couldn't reach the right angle of cut and body in place.
So you think OneWay's Wolverine can do this asymmetric grind without any problem? I don't think it will be done easily, unless you come up with some kind of addition to the jig.

Jake, I've little experience turning bowls, but I see a pattern in the way you present the tool when you're getting catches. It looks to me like you begin the cut with the flute at 1:00 o'clock and the tool skates off to the left. Then you correct the flute to 2:30-3:00 o'clock and it proceeds OK. The experienced bowl turners need to validate the significance of my observation, but that happens over and over in your video.

Your observation is right on the money my friend.

Jake.......

You look to have spent a great deal of effort perfecting your double bevel grind.........but, it's my opinion that your long edge on the left side of the flute is your problem. I haven't used your progressive bevel grind on the internal shape of a bowl, so you can take my thoughts for what they're worth. It does look like the shape itself would be prone to catching with the way you are presenting it to the wood. There is very little positive control on the left side of the flute, but this gradually gets better as the tool progresses closer to the center where it levels out.

I am mostly using a standard bowl grind done at various bevel angles. This is done with the Wolverine using the V arm. Certainly my grind, and style is completely different than yours. Most of my internal cuts are near the tip and slightly to the right side of the flute. A long sharpened edge is not needed here in order to present the most useful cutting edge to the wood.

ooc

It took me some feelings -- as I was reshaping this gouge It was hard to do something different to it -- specially, when I was thinking, what if it doesn't work...man, I'll end up wasting so much HSS Metal off of my gouge!

It works great, it just has a horrible performer at the time this video was recorded... It's due to some poor understanding of video directing... Anyway, I'll try to do a proper video. Thanks for the info on what you prefer on gouges.

Cheers

Interesting to watch. You need to spend more time using the nose of the gouge. If you lay the bottom of the flute parallel to the curve of the piece, you can stop those big wood-wasting kick-outs when hollowing. I use a plunge and roll technique for hogging, personally. Gouge is ground more or less symmetrical, because I, too, freehand on a grinder.

Hollowing sequence. http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=HollowTwo001.mp4 The pillar is left in for remount of the dry piece after the wood cures. Shavings, not chips are a good thing. You get chips because of the high pitch angles you use. If you lower the pitch for broad, not deep cutting, your control and surface would benefit. You can get a good idea of my flute direction by watching the shavings eject. The run around the flute and depart at about 90 degrees to the nose.

Here's seasoned wood with a nice, controlled entry. First is to take energy away from the turning by slowing the lathe down, second is to enter as narrow as possible, under control. http://s35.photobucket.com/albums/d160/GoodOnesGone/?action=view&current=Inside.mp4 Second sequence is back to the finishing gouge.


I finish with a completely different gouge. It's all nose. http://s108.photobucket.com/albums/n28/MichaelMouse/?action=view&current=CherryPeelIn.mp4 Even thin shavings on dry wood often hold together across the endgrain, because there's so little stress when you slice.

I use a gouge ground similarly to your left side for hollowing endgrain, but it's a shallow, "detail" gouge. http://i35.photobucket.com/albums/d160/GoodOnesGone/a63b77ab.jpg

It shaves the interior smoothly and ejects the shavings down the flute. Sure beats scraping, hosing and maybe jamming on the dust! http://i35.photobucket.com/albums/d160/GoodOnesGone/725a28f2.jpg

Hi Michael. Thanks my friend for posting your videos. I think I've seen them some time ago. They are great and I think you should put them up on YouTube. There are so many people out there who seek for advice, and they always search for it on YouTube. So, I think it'll be much better if you upload your videos there... By the way, in your video, where you're using a detail gouge, how do you end up doing the very bottom?

If the flutes are too up and down, the wings are more prone to catching. I have my gouge rolled over between 45 and 90 degrees all the time. As John said, moving the handle more away from you will help keep the skipping to a minimum.

I have heard of and seen the grind you use, but can't see that it has any advantages. I only have one swept back grind gouge, the rest are more of a fingernail grind. I use scrapers for roughing.

robo hippy

Thanks Reed very much agree with you all on the way it was turned. But, like I said, I just wanted to show the sharpening technique.

Anyhow----I'd love to see some other sharpening techniques on this asymmetric grind. I heard that Richard Raffan has a video on sharpening asymmetric grind...I don't know if I can rent the video somewhere online to watch it. If you know of any other instructional video on asymmetric sharpening, please let me know.

Cheers

 

[john lucas]

Jake it was actually a great video. Sharp and in focus. We could actually see your gouge and how you were using it. That's way ahead of 90 percent of the videos on the web.
If you position the flute at about 45 degrees or say 2:30 when doing a push cut on the inside your grind will work fine. I still say you are getting the kick back at the beginning of the cut because you don't have the tool handle over far enough. Try going very far over with the handle. Further than you think you need to go. Once the tool starts position the handle where it needs to be to make the gouge go in the direction you need to go.
Placing your thumb the way you don't won't stop a kick back if your off very far. If you are close it does help. It might make it easier to understand the direction of the bevel if you position the flute at 3 oclock.
Watch my video on turning a cove. The part where I discuss using a spindle gouge would be similar at the start of the cut to starting into a bowl.
http://www.youtube.com/watch?v=DSybPNw4F1o

 

[Jake Gevorgian]

Thanks John, that video was shot with my iPhone

What I wanted to say is that the tripod was on my way when I was turning... And I couldn't be in the right position, because I would have closed the camera. Anyhow, today I gave a try to some more video shots using a different position (the tripod was still close, but at least I could stand correctly)

Here is a test cut on an end grain. The wood is very fuzzy... It's some scrap piece.

http://www.youtube.com/watch?v=GXYc_JuK1gk

 

[Jake Gevorgian]

By the way, your video is great. I have seen it few months ago. It's the best instructional video I can tell (available for free

 

[Jake Gevorgian]

Here is another test cut. http://www.youtube.com/watch?v=wEdgyQvBeBY

 

[Jake Gevorgian]

And here is the final test http://www.youtube.com/watch?v=Hk_Sd6MpQgc

 

[MichaelMouse]

I take it you don't have a bandsaw? Don't see a lot of sense keeping four corners unless your end product is going to be square.

Position on the camera is tough, even if you have a spouse doing the cinematography. S/He may not grasp the idea that it's how the tool meets the wood that you want. Your best with words and hope the pictures help is all you can do.

Think what John is saying about rim entry is that you enter as narrowly as possible. You can enter with a high pitch angle or low. Main thing is the swing in that follows. Take a quick peek at the cured maple entry in the videos I referenced. Position the fulcrum properly and swing in. As soon as you get a tad bit removed, you have the option to swing to cut with the side of the gouge. I learned to take the point of a skew or parting tool and make a stopping scrape to keep the gouge from being thrown outward way back when. Works reliably, but the guy teaching me was an Oland Tool type, so he didn't have all the options we gouge users have.

I don't use a detail gouge in any of the videos. The long-grain hollowing in the stills is where I use one. I generally clean the end grain bottoms with my ring tool or a fingernail grind gouge. The videos use deep gouges for digging or forged for finish cuts.

 

[Jake Gevorgian]

We have hot weather in California! Why do I need to round up the square? It keeps me cool. :cool2:

 

[Dale Miner]

I think the runs you get when presenting the gouge are a result of the cutting egde not being perfectly neutral at the point of contact. The assemetrical grind effectively makes the cutting edge shorter on the swept back side of the gouge. When the edge makes contact, it is at an angle to the rotation, and causes the gouge to skate. Brute force to hold it in posititon until there is enough notch for the bevel to register against is one way to control the skate. When I try using brute force for control, it always fails me at the worst time. You might try closing the flute a few more degrees at entry to bring the longer part of the gouge into a more neutral mode and then open the flute after the cut is established, or, try grinding the conventional side of the flute just a bit shorter. Grinding that side of the flute a bit shorter will result in the portion of the egde making initial contact more neutral and less apt to skate.

I do see the advantage in having the right side of the flute with a more blunt bevel, but I don't think I am going to give it a try. I keep a conventional grind with a blunt angle in the tool rack for those parts of a bowl that need it.

I also see the advantage of using the soft spot of the belt to get a convex bevel for use inside a bowl. I see no advantage of a convex bevel on the outside of a form though.

 

[Jake Gevorgian]

Excellent notes Dale. By the way, after standing correctly, I managed to position the tool the following way:

Handle down, so the cutting edge was about 30 degrees.
Flute closed and even tilted some more.

But, what I'd like to point out here is that, by doing a freehand sharpening, the tool might not work as it used to work previously---there's a little accent in there.

I so wish there was a jig for it. John Lucas said something can be done with a Wolverine jig, but I'm trying to figure out from where to get my third hand in order to move the jig up and down ***little humor here!***

 

[john lucas]

Jake I'll be in the shop tonight, at least for a little while. I'll see what I can come up with on the jig thing. I know what you mean about sharpening angles. That's why I went with a jig. When I was new every time I sharpened it was a little different, usually with lots of facets. I should have gone into shaping diamonds because I was really good at getting all sorts of facets.
I really don't think you need the asymetrical grind and it's much easier to do either the Ellsworth or traditional grind. If you watch my sharpening video's you will see the Stewart Batty grind which is similar to the right side of your gouge only both sides have the same grind. This is done with just a tool rest so it would be an easy grind to do on your sander. The Ellsworth or Wolverine jig type of grind is like the left side of your tool. Either one work fine for turning bowls. You would have to rig up a sort of pivot point for either the Ellsworth or Wolverine jig to be able to use your belt sander but it does work, I've done it on my sander.

 

[Jake Gevorgian]

Thanks John. Would love to see what you've came up with. I'm also working on some ideas here -- just passing them into the paper. No scientific tests have been performed yet, especially when I have to work in the cabinet shop all day...at the end of the day I'm pretty exhausted. Ah, the paperwork is still due! Darn, I hope my clients don't find me out here.
Cheers

 

[john lucas]

Jake I played with the jig a little. It would be a pain. you can use the wolverine jig to do the nose and left side but you would have to slide the jig to the right and up to grind the right side. That won't work with the V arm and you would probably be doing that movement somewhat freehand anyway.
In reality the solution is not the grind you are using it's how you are using the tool. I would love to make a quick video to show you but I'm working the next 14 days straight with very little time to play in the shop. Maybe after graduation May 6th I'll have some time although I believe we have some sort of assignment on May 7yh also. College Photographers never get to rest, especially when they are interviewing and hiring a new president.

 

[Thomas Stegall]

I think John described it beautifully. Proper tool presentation when starting a cut makes all the difference. The rudder anaolgy was also quite accurate.