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Thread: Question About The Combined Bevel Angle Of Skews

  1. #1
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    Question About The Combined Bevel Angle Of Skews

    I'm fairly new at turning and up to a few days ago never touched my skews. However, I've decided to start practicing with them to try and gain some proficiency. I've been practicing on 2" x 2" cherry spindle blanks.

    For those of you that are already proficient with a skew I have a question involving the combined bevel angle. I have two 1" flat skews with one skew ground at a combined bevel angle of 25 degrees and one ground at a combined bevel angle of 45 degrees.

    I'm finding it is much easier for me to control the skew with the combined bevel of 25 degrees than the one at 45 degrees.

    Does this make sense? I'm asking because some things I've read suggest it should be the other way around.

    I would appreciate your comments

    Thank you

  2. #2
    Combined angles of 25 degrees, to me at least means your platform was set to 12 1/2 degrees. That is pretty flat. It seems the range is 20 to 30 degrees on each side, but like turners themselves, there are a lot of differences. If you are at 45 degrees on both sides, that is pretty blunt, but a fairly common angle range for bowl gouges and spindle roughing gouges...

    robo hippy

  3. #3
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    Quote Originally Posted by Dom Garafalo View Post
    I'm fairly new at turning and up to a few days ago never touched my skews. However, I've decided to start practicing with them to try and gain some proficiency. I've been practicing on 2" x 2" cherry spindle blanks.

    For those of you that are already proficient with a skew I have a question involving the combined bevel angle. I have two 1" flat skews with one skew ground at a combined bevel angle of 25 degrees and one ground at a combined bevel angle of 45 degrees.

    I'm finding it is much easier for me to control the skew with the combined bevel of 25 degrees than the one at 45 degrees.

    Does this make sense? I'm asking because some things I've read suggest it should be the other way around.

    I would appreciate your comments

    Thank you
    Dom,

    You said the 25-deg skew is easier to control. What do you mean by "control", exactly? Is is easier to get a smooth, clean cut? Easier to avoid a catch?

    A few months ago I measured the angles of all my skews and found angles from about 22-deg to over 50-deg. I sharpen by hand and don't set a particular angle but usually just repeat the angle that is already on the skew. When I reach for a skew for a particular cut, I may get a smaller or larger angle depending on the cut.

    I use a skew a lot and my experience is, in general, a 25-degree skew will cut easier and cleaner than the 45-deg skew. However, the 45-deg is, in general, more forgiving than the smaller angle, i.e., less grabby if not well controlled, so I tend to give that to a first-time skew student. (and BTW, the skew is the first tool in the hand of a brand new turner - I think it is the easiest and quickest way to really understand how the bevel, edge, and tool presentation work together to make the cut. This applies to every other "cutting" tool.)

    However, I find a lot depends on several factors: the type and hardness of the wood, the angle of the grind, whether it is rounded or straight, and perhaps even the speed. I forget where I read it but one author recommends a different included angle for hardwood vs softwood. Even more important might be how the angle of the edge to the wood and you hold the skew move during the cut. The diameter of the work is also a factor. The specific wood may even be a factor - I have some particular osage orange that will chip badly when I use a 25-deg skew on thin spindles but a larger angle skew works better.

    2x2 cherry blanks sound perfect for practice. I generally turn with the lathe running about as fast as it will go but if beginning with the skew you might try turning the lathe speed down as low as possible at first. For a new student I actually turn the lathe by hand until they get the hang of making shavings. And I applaud you for tackling the skew! I've met experienced turners who never learned use the skew and joke about it being good only to open cans or as a scraper! When I started turning people told me to stay far away from the evil skew. But from the books the experts were all using skews. Hmm... I decided if they could do it I could too and today it is one of my favorite tools (for spindle turning).

    JKJ

  4. #4
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    Reed, I use Oneway's Wolverine grinding set up along with their skew jig to achieve the combined bevel of 25 degrees on one skew and a combined bevel of 45 degrees on the other skew.

    I agree, the combined bevel of 25 degrees is quite flat but seems to work better for me. With the skew having the combined bevel of 45 degrees it seems I have to lift the handle so much higher to get it to cut that it feels awkward.

  5. #5
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    You said the 25-deg skew is easier to control. What do you mean by "control", exactly? Is is easier to get a smooth, clean cut? Easier to avoid a catch?
    John, it's exactly as you state- with the 25 degree skew I find it easier to get a smooth clean surface and cut. I present the skew to the wood at a 45 degree angle with the cutting edge at about center and as long as I pay attention to keep the toe up, so far I have not had a lot of catches.

    One exercise I've been doing is to use the skew with the 25 degree bevel to completely round a 2" x 2" blank without the use of a spindle gouge. Much to my surprise, it works quite well but I'm just a newbie.

    Thanks for your comments.

  6. #6
    I guess some of it depends on your tool rest height. As a bowl turner, I don't use a skew much. Some skew users tend to have the tool rest at center height and have the skew more up on edge. Some have the tool rest above center, and have the skew closer to flat on the tool rest. Both ways work. I watched Eric Loffstrom use a skew for boxes, and he only used the peeling cut, which left an excellent finish...

    robo hippy

  7. #7
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    About 2 1/2 minutes in Allan Batty discuss different bevel angles and why.
    Sounds reasonable to me and I have always used about 40*.
    Add..BTW, Alan Lacer suggest a bevel length 1.5 X the thickness of the blade. If you work through the math it is almost the same 40*.
    https://www.youtube.com/watch?v=KfeLAHQSbqk#t=15
    Last edited by Michael Mills; 08-22-2017 at 7:24 PM.
    "I became insane, with long intervals of horrible sanity." - Edgar Allan Poe

  8. #8
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    Quote Originally Posted by Dom Garafalo View Post
    One exercise I've been doing is to use the skew with the 25 degree bevel to completely round a 2" x 2" blank without the use of a spindle gouge. Much to my surprise, it works quite well but I'm just a newbie.
    That is an excellent. I regularly use just the skew to rough and shape a spindle blank, moving to a spindle gouge only to add detail such as coves.

    I couldn't find the paper with all my skew sharpening angles but I think my most-used skews are between 25 and 35-deg., using the sharper skews especially for hard, fine-grained woods like dogwood or hard maple. My favorite skews for detailed work are 1/2" and sometimes 1/4" round skews for small work, 3/4" to 1-1/4" wide skews for larger diameters. I have a couple of oval skews that seem easy to use. I generally reach for one of my favorites then if I'm not satisfied with the cut (as long as it is sharp) I'll try one with a different grind. I've mentioned this before, but when making any cut, planing a cylinder, hollowing a bowl, I like to make lots of practice and test cuts while removing wood. I might try different tools and some different shapes on the surface, then cut that away and repeat. As I get closer to my desired surface I make a series of finish cuts, each as perfectly as I can manage. By the time I get to the final finishing cut, my hands and stance and control for that particular cut and tool are well practiced!

    Most people teach to keep the cutting edge well below the center line - I think that is to give you a little extra distance from the long point in case the attention wanders! However, truth be known you can actually cut above the finish line as long as you are careful and don't let the point itself touch - the edge is still well supported by the bevel. I wouldn't try this for heavy cuts since the grain could get grabby and pull the edge a bit deeper which could cause a problem. But since most cuts are light I regularly use the edge above the center too - hey, it's sharpened all the way along the edge, why waste it! One thing to be sure of, if you haven't, is that there aren't any sharp corners down the length of the tool - round them over with stones or diamond hone or even a belt sander so they don't dig into the tool rest. I like the way Doug Thompson makes his with a radius machined down the entire length of the short edge, the one that usually rides on the tool rest for planing cuts.

    You will find that after you get some experience you will never get a catch in normal use. The only catches I seem to get are from not paying attention when moving a tool around when the lathe is spinning and accidentally run it into the wood! I think one problem people have is tenseness in the hands, arms, and shoulders, holding the tool with a death grip. One practice technique is to hold the end of the handle of a skew (or spindle, or even a bowl gouge) with just two fingers and make the cut with just one or two fingers near the tool rest.

    If you haven't seen it, this video by Richard Raffan might be useful. https://www.youtube.com/watch?v=jOvF5f1phhY

    JKJ

  9. #9
    The oft used "formula" of the length of the bevel being 1.5 times the thickness of the skew will always produce a combined angle of just barely under 40* - for whatever that may be worth to you.

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