Help needed - Skew Sharpening problem

[Tim Thiebaut]

Hi All, I think I have sharpening of the gouges down pretty good now, but when sharpening my skews this evening I ended up with an issue..my "1 oval & "1 1/4 flat skews came out with a concave spot, a low spot...between the long and short points. My 5/8 came out perfect and sharp as a razor. The longer ones are sharp but with the low spot and the ends dig in before I can ride the center of the skew...what am I doing wrong. Is this because these skews are wider then the grinding wheel itself? That is the only thing I can think of since my 5/8 is fine. What can I do to fix this issue? Thank you for any help you can give me, I feel lost not being able to grab my skews. Tim


PS - I do have the skew grinding attachment for the wolverine jig, while sharpening on the left side short point is left, sharpening on the right side short point is right.

[Roger Chandler]

Tim,

A little concave shape is desirable in a skew. That way honing with a stone to do touch up is easier. You use the cutting edge and the high shoulder for 2 contact points and hone with the stone. This is the way that Alan Lacer teaches on his videos and in person at his demos. I have the videos and have been to his demos as well.

I would recommend that you get his video, "The Dark side, the Sweet Side" as it will teach you the proper way to sharpen a skew, and you will learn great technique from him for the skew! One of the best I have seen!

[Tim Thiebaut]

Hi Roger, it is probably the way I explained this, I wouldnt mind at all if it was just like Alan's...but think exactly oposite of that, concave not convex....so that the S and L points are touching if you place the blade against something, and there is a concave bow like the St. Louis arch between them....Tim

[Gary Conklin]

Check this out:

Link (http://www.youtube.com/user/capneddie#p/u/43/QYCAdFOCcJA)

[Brian Libby]

Also the AAW has a DVD "Woodturning: Fundamentals of Sharpening".

[Roger Chandler]

Hi Roger, it is probably the way I explained this, I wouldnt mind at all if it was just like Alan's...but think exactly oposite of that, concave not convex....so that the S and L points are touching if you place the blade against something, and there is a concave bow like the St. Louis arch between them....Tim

Okay Tim to make sure you and I are on the same page.....at first I typed convex by mistake, then edited to say concave. Concave is when the grind is a little like a hollow grind, which is what you want, a little dip between the edge and the shoulder. Then the edge and the shoulder can be used as two points to hone with a stone. If you have a convex shape [mound in the middle of the edge and the shoulder] then you need to regrind to take that off.

I highly recommend you get a video and learn to do it the right way.........it will save you a lot of tool steel! Hope this helps!

[Jim Burr]

Hey Tim...to a point..no pun intended...skews are to be sharpened on the side of the wheel. PLEASE keep in mind that most wheels are not stabilized for lateral stress, so light pressure is required. A good edge is acheived however!! Kinda funny...I did mine about 4 hours ago with this method.

[David E Keller]

I prefer the grind as shown in the link that Gary posted... I like it better than the hollow grind that Alan Lacer and others recommend. I use my grinder free hand, but the belt sander is an interesting idea. I hone with a diamond card quite frequently while using the tool, and I don't find the need to use the grinder all that often. I need to make one of those buffing discs like Capt. Eddy, too.

Oh yeah, I also like a curved edge rather than the skew being straight across the end... Sort of the opposite of what you've got going now I think.

[Jake Helmboldt]

Tim, I'm confused. Roger is refering to the concavity on the bevel; what is called hollow ground. That is what I thought you were talking about as well. If I am understanding you, you are saying the actual cutting edge is curved? If so, then you likely are moving the end of the handle as the blade remains in the same place on the wheel. The tool edge needs to sweep across the wheel.

You need to either slide the edge across the wheel in a linear fashion, or rotate it slightly so you get the radiused edge. Putting a radius on an oval skew is difficult but pretty easy on a square skew. I prefer to use a basic platform at the wheel to control the swing.

[Roger Chandler]

I have seen Mike Darlow, and Alan Lacer's videos, and seen Lacer up close on his demo. I think they prefer the concave [hollow grind] because they say you get better cuts and better control with that grind. It seems to me that a convex hump would make control harder, and when you go to do some cuts like the pummel cut on a table leg, that it would be harder to get the precise small shaving action sometimes needed to finish cut a shoulder cut on a pummel.

I guess there is more than one way to do most anything, but the recognized masters at this seem to agree that the concave is the way to go. I have also watched 3 other demos by skew "experts" and they also agreed with Lacer and Darlow. I personally have not tried the convex, so I cannot tell you for certain from my own experience, but I do know the concave works really well from my own experience.

[Dan Forman]

I think a picture of the offending skew would be in order, would probably make the problem and solution clearer.

Dan

[Bernie Weishapl]

I like the hollow grind on my skews. I use the front of the wheel and hit the heel first dropping it into the hollow. Then I hone.

[Jake Helmboldt]

Folks, take a look at my previous thread. I don't think this is an issue of hollow ground bevels. Tim seems to be saying his edge is concave.

[Michael Mills]

I assume you are not talking about the bevel at all and that you want a straight edge tip to tip (not curved like Lacers).
The only thing I can think of is you are not keeping it straight as you go from side to side.
If you can put a finger on the back side of the grinding rest you should be able to get a straight edge sliding side to side (The same way you would use your hand as a guide for planing or using a spindle roughing gouge). You will have to spend a little more time at each tip to get it straight again.
If not this, then I can only think your wheel is not flat on the face but is slightly curved and need to be flattened.

[Tim Thiebaut]

Folks, take a look at my previous thread. I don't think this is an issue of hollow ground bevels. Tim seems to be saying his edge is concave.


Yes...the edge of the skew is what I am talking about. The cutting edge. As I said I have the wolverine jig Skew attachment I am useing, the butt of the tool is held stationary in this while sharpening. I will go mess with it a while and see what I can do if it dosnt work out I will get some pictures.

@ Jim Burr - You sharpen your skews on the "side" of the wheel? I have never heard this before, and would be impossible to do it that way with the wolverine setup.

[Keith Westfall]

Have you trued the face of your grinder wheel? if it is not flat, it may give you problems...

[Michael Mills]

I do not have the wolverine but after I posted I did watch the youtube video by Woodcraft. I watched two and they newer showed a wider skew. If I understand you, the butt of the tool is stationary in the rest. If so the only way to grind across the width (except on a narrow tool) is to swing the cutting edge side to side on the wheel. I think that would cause what you are describing. It would be like a compass, if the point (the butt) is fixed, the pencil (the edge) has to start forming a circle any time it is moved.
The butt of the tool needs to be kept at the same angle to the wheel and the entire tool moved side to side.
My idea of keeping your hand against the back of the rest will probably not work because the rest is too narrow.
It would be quick to make a little jig to slide on top of the rest and you would get the same 70(?) degree every time.

[Tim Thiebaut]

I "think" I may have figured this out, and before I start...yes I did true up my wheels today, I have been unable to find a diamond wheel dresser anywhere here in town that I went to so I had to order one on line and it just got here this evening...I have been waiting on this before attempting to sharpen my skews as I didnt want the wheel to mess them up, the wheels had small grooves in them from sharpening my gouges. To help in the future I also ordered a second wheel so I can do skews on one side and keep the face fairly square as opposed to the wheel I will do only gouges on from now on. The larger skews I have are so much wider then the wheel itself there is alot of the tool that is out in mid air while sweeping the tool from side to side, while the middle portion of the tool is almost always in contact with the wheel, I believe this is what caused my issue of the middle of the tool being ground back further then the sides out towards the S and L points. I spent a good while this evening practising with it and varying pressure on the skew while sharpening it until I was finaly able to start getting an even grind all the way accross the edge of the tool.

Thank you for being patient with me....sometimes I feel like I dont know what the heck I am doing and am glad I can come here and bounce things of you all...Tim

[Derek Stockley]

I was having a bit of trouble grinding my oval skews too. I tried an arrangement similar to the wolverine skew grinding attachment that I banged together with a couple of blocks of wood, but I wasn't happy with the result, basically because I'm just not very skilled at the grinder. I too was causing myself lots of grief due to un-even grinding, twisting and so forth.

After reading a bunch of forums, I found some ideas that inspired a jig to hold my skew flat on the grinder's tool rest. The tool is held in place by a pair of opposing wedges, similar to a moulding plane iron, and oval skews are kept centred accurately by V notches cut into the jaws.

181479

I wrote a blog post (http://www.makingsplinters.com/2011/01/sharpening-an-oval-skew-without-creating-facets/) a couple of weeks ago about it that includes exploded sketchup drawings and additional notes on designing it, but the short version is that to get a radiused skew, you put a single pin on it, and to get a straight skew, you'd want to glue a straight fence on each face at the angle you want. The pin pivots on the rear edge of your flat tool rest and gives you a consistent cut. The pin's position relative to the blade establishes the radius of the curve on the blade. Alternately, the fence would slide across the rear edge.

[Keith E Byrd]

Gary,
As a new turner I have had trouble getting the skew to be a skew - I was getting pretty good with it as a scraper! But I watched this video, sharpened my skews and for the first time I actually skewed a piece of wood!
Thanks for posting it!