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  • Lathe Chatter Frustrations

    I get a lot of chatter towards the outer edges of my turning projects. This is mostly on face lathing when I am hogging out material. I recently got some carbide tools in hopes the chatter would go away but it didn't seem to make a lot of difference.

    What happens is when I put the tool on the outer edge (for instance a bowl gouge), the piece always seems to want to force a catch. Tools are sharp. Thickness is a good 1/2". I am taking super small bites with the flute at maybe 2 o'clock traveling from outside to center. Scrapers and other tools do the same thing. Square and round carbide tools also the same thing. If I take any more than a super light pass off I get this. This latest piece only has a diameter of around 6" and length of 8". Initially I supported it with a live center until I lathed in a tenon to use with my Nova chuck.

    I am a relatively new lather. Any ideas what I am doing wrong? One thing I will say is I have no idea what RPMs to run my variable speed lathe. For now I have it at around 800rpms.
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  • #2

    Re: Lathe Chatter Frustrations

    You should start with the tool facing 3 o’clock to start off, till there is a shoulder to keep the tool from skating out and catching.

    Shatter is where the wood wants to get away from the tool and it can because the wood is not strong enough and it will deflect, sharper tool and lighter cuts do help, also some shapes will very easily start shattering where other shapes will not or less so.

    A straight cylindrical shape is not as strong in preventing distortion as a curved shape, it will easily deflect away from the tool, where a curved shape is stronger and will not change shape as easily.

    The other thing that helps to prevent the shattering is to leave more wood in the wall so it is stronger and only turn an inch or so thinner at the time going down, NEVER go back up higher for another cut or it will catch, so you do have to feather the next cut into the other one.

    I have also used my left hand to steady the wall while cutting and holding the tool with the other hand, my thumb helping to steady the tool.

    So smaller sharp gouge and lighter cuts plus steadying the wall are all called for, practice practice practice, and practice some more


    Have fun and take care
    Leo Van Der Loo

    Comment


    • #3

      Re: Lathe Chatter Frustrations

      Originally posted by Leo Van Der Loo View Post
      You should start with the tool facing 3 o’clock to start off, till there is a shoulder to keep the tool from skating out and catching.

      Shatter is where the wood wants to get away from the tool and it can because the wood is not strong enough and it will deflect, sharper tool and lighter cuts do help, also some shapes will very easily start shattering where other shapes will not or less so.

      A straight cylindrical shape is not as strong in preventing distortion as a curved shape, it will easily deflect away from the tool, where a curved shape is stronger and will not change shape as easily.

      The other thing that helps to prevent the shattering is to leave more wood in the wall so it is stronger and only turn an inch or so thinner at the time going down, NEVER go back up higher for another cut or it will catch, so you do have to feather the next cut into the other one.

      I have also used my left hand to steady the wall while cutting and holding the tool with the other hand, my thumb helping to steady the tool.

      So smaller sharp gouge and lighter cuts plus steadying the wall are all called for, practice practice practice, and practice some more
      It is hard to explain what is happening. I will try to get a video to post. Any advice for lathe speed?

      Comment


      • #4

        Re: Lathe Chatter Frustrations

        Try other ways of doing things, try a higher speed, if your using a gouge you should be rubbing the bevel that avoids catches, are you cutting at just above center? as you are learning (aren't we all, all the time) learn how to rotate the gouge and experiment with the difference in cut at different angles, just be sure you are rubbing the bevel.
        I usually completely turn the outside of a bowl before I start to remove the inside, work from the bottom of the bowl towards the top edge, when the outside is finished turn the bowl around and hold by the bottom then work from the top edge down to the bottom inside the bowl.
        Show some pictures of what you are doing there are plenty of people who will help you.

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        • #5

          Re: Lathe Chatter Frustrations

          For speed what ever you are comfortable doing, no right no wrong, but faster is better, just be sure to be safe.

          Comment


          • #6

            Re: Lathe Chatter Frustrations

            Every time I see this thread listed I think it's titled "Lady Chatterley's Frustrations"

            ...Umm, OK. Carry on.
            WoodBob likes this.

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            • #7

              Re: Lathe Chatter Frustrations

              Keep your tool rest as close to the work piece as possible. The shorter the chisel length hanging over the tool rest, the less chatter and the easier it is to hold safely.
              Egon likes this.

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              • #8

                Re: Lathe Chatter Frustrations

                Since you have a variable-speed lathe, try adjusting the speed just in case you are getting a bit of resonance making the workpiece vibrate a bit more. I don't really think this is the problem but easy to try.

                Your workpiece isn't that big and does have a 1/2" wall but it is 8" long. If I were having the same trouble I'd try a bowl steady near the end. This is the same idea as Leo's left hand on the bowl but would be more rigid.

                Since you admit to be a fairly new turner it may just be a case of "you have to learn a bit more" and I assure you we have all had the same problem at one time or another.

                billh

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                • #9

                  Re: Lathe Chatter Frustrations

                  Replace your headstock bearings. A tiny, undetectable amount of wear in them will result in chatter, especially on the larger items. I had the same problem on my first lathe, it didn't start out that way but developed over time. I tried all the suggestions mentioned above, nothing worked. Changed bearings and the problem disappeared.

                  PS - be certain to use the best quality bearings. Makes a big difference.

                  Comment


                  • #10

                    Re: Lathe Chatter Frustrations

                    Originally posted by Art in Prince George View Post
                    Replace your headstock bearings. A tiny, undetectable amount of wear in them will result in chatter, especially on the larger items. I had the same problem on my first lathe, it didn't start out that way but developed over time. I tried all the suggestions mentioned above, nothing worked. Changed bearings and the problem disappeared.

                    PS - be certain to use the best quality bearings. Makes a big difference.
                    The lathe is new but it is a cheap(er) one. It is a Wen. The chuck is also new, a Nova. I did find the lathe is not very level so in addition to leveling I will also check for any out of spec headstock situations. I watch the videos on YouTube and a project like I am doing takes them no more than 10 minutes start to finish. It's depressing!

                    Comment


                    • #11

                      Re: Lathe Chatter Frustrations

                      Originally posted by WoodBob View Post

                      The lathe is new but it is a cheap(er) one. It is a Wen. The chuck is also new, a Nova. I did find the lathe is not very level so in addition to leveling I will also check for any out of spec headstock situations. I watch the videos on YouTube and a project like I am doing takes them no more than 10 minutes start to finish. It's depressing!
                      The good part to your depression is "its a big learning curve that will absorb a lot of your time and then become very rewarding, just when you master one piece of work/wood you put another type of wood on the lathe and you start learning all over again, its endless, you get a lot of value from your cheap machine, don't have any time off its easy to forget what you learnt unless you want to start all over again.

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                      • #12

                        Re: Lathe Chatter Frustrations

                        You could use a bowl steady, (buy or make) that does help with vibration.

                        https://oneway.ca/Bowl%20Steady?search=steady

                        and as you bring up, yes cheap or low cost asks for payment all the time in extra things and effort when using it, goes like pay me now or pay me later, though expensive by itself does not make everything nice and easy either.

                        One of the problems that was already brought up is the bearings, less costly ones do have more clearance in them and give play which can become chatter, also the short headstock used in small lathes bring the bearings closer together again making things worse, however it can be overcome, but it takes effort and experience and or extra accessories.

                        Have fun and take care
                        Leo Van Der Loo

                        Comment


                        • #13

                          Re: Lathe Chatter Frustrations

                          Here is a video. It was chattering a bit here but I was just testing the camera setup really. I did not go out to the edge where it is really bad. But any comments on my technique?

                          https://youtu.be/BwMvqRtYsBw

                          Comment


                          • #14

                            Re: Lathe Chatter Frustrations


                            Maybe you can compare what you do with a very knowledgeable turner, yes he goes pretty fast, but you can look as many times as you need, look at his tools and how he holds them, there are 2 videos as you can see.

                            https://www.google.com/search?client...UTF-8&oe=UTF-8

                            Having different wood that are not the same does not help you, and as I said before cylinder shapes are more likely to give you shatter.

                            We can’t see the tools cutting edge/shape, I would not hollow a shape like you have there like that, but rather in a cone like shape, so start at the center and next cut wider and deeper and on like that, the picture shows this and even in your piece you can do this till you are deep and then flatten the bottom, don’t use a bowl gouge as a scraper, have it cut,

                            Click image for larger version

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                            KenL likes this.

                            Have fun and take care
                            Leo Van Der Loo

                            Comment


                            • #15

                              Re: Lathe Chatter Frustrations

                              I suspect that the chatter issue in your new lathe can be cured easily. I had the same issue way back when and it was fixed by two things: the cone angle of the live centre needed to be reground to be a shorter cone with a much less acute angle and I changed the way the tools were sharpened as Leo said. I am not a proponent of high lathe speeds to try to cure problems by bullying them out of existence but rather figuring out what the underlying cause is and then repairing the problem. It's a bit like driving fast on a rough road to pretend it is smoother; it doesn't work like that because the energy is still going somewhere.

                              Once you get some chatter, more turning makes it get worse and the worst part is that it becomes self-perpetuating until the root cause is determined and eliminated How level your wood lathe sits will have no influence on this issue unless the bed is being twisted. Art's advice to check the bearings in the head stock (new or not) might uncover some clues, is easy to do and eliminates or reveals one possibility.

                              Scrapers seem to be a mixed bag to me; their tendency to chatter at higher turning speeds is remarkable but, for me at least, they are the most forgiving tool in wildly varying grain. I agree with Leo 100% that a cutting tool should be used to cut and not to scrape; the geometry is all wrong. Some folks never use a scraper; and others never use a skew; I use both on spindle turning (eg a rolling pin or pen) and scrapers on bowl turnings. I made up a steady rest using Lee Valleys polyurethane wheels but was so unhappy with it that I scrapped it and am going to try again because it helped some for thin bowls but was a terrible thing to adjust.

                              I don't know if any of that helped but please do let us know what (if anything) you find.

                              Ken

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