"No Mandrel" needed for Pen Finishing

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  • "No Mandrel" needed for Pen Finishing

    I discovered how to finish a pen without using a mandrel and it works great. First, the reasoning: I have had trouble using CA with oily pen blanks such as ebonies and cocobolos. I like CA and won't give that up so I had to deal with the issue from a different perspective. CA would often stick to the bushings, even if coated with a light coat of wax. When separating the bushing from the blank, quite often the CA would separate just a barely visible smidgen from the blank at near the end, showing up as a light spot.

    This happened on about 50% of the pen blanks of ebony (Japanese persimmon) as well as other and on cocobolo. I have wiped the blanks with acetone and boiled them, but still had the problem. UNTIL . . .

    Someone on the pen turning forum at IAP mentioned mandrel-less turning a few months ago. Then when a lady had problems with bushing dust getting onto her blanks last week, one fellow mentioned the Mandrel-less finishing.

    I decided to give it a try. It requires a "dead drive on the head stock end. I do not have one but I had an aluminum rod 20mm in diameter and about 10 CM (4 inches) long, so I made a "dead center drive for pen finishing. I don't use it for getting the blank into the general shape but for finishing. I have done 4 pens with ebony wood and no problems so far.

    Picts:

    On this pict, you can see on the left end of the blank how the CA often separates from the blank when removed from a bushing. If you double click on the pict it will enlarge and then the separation can be seen at the point that the reflection meets the left end of the tube.



    My dead center, that I use in a 2MT chuck drive:



    For people in the USA, you can order a "dead drive" for $5 - $10 plus postage from several places.

    Also, if you want to see the original post on IAP, go here:
    http://www.penturners.org/forum/topi...TOPIC_ID=26155
    Last edited by leehljp; 07-22-2007, 12:57 AM.
    Hank Lee

    Experience is what you get when you don't get what you wanted!

  • #2
    So why do you want to use a non-live tailstock for the pen? If you're running the lathe up, wouldn't the friction on the tailstock cause at the very least discoloration of the pen body? Or am I just totally missing something here?

    For oily woods I've found that using sanding sealer first works pretty good, and also wiping it down with naphalia and then applying the thin CA while it's still wet-ish works good too.

    Comment


    • #3
      Originally posted by final_t View Post
      So why do you want to use a non-live tailstock for the pen? If you're running the lathe up, wouldn't the friction on the tailstock cause at the very least discoloration of the pen body? Or am I just totally missing something here?

      For oily woods I've found that using sanding sealer first works pretty good, and also wiping it down with naphalia and then applying the thin CA while it's still wet-ish works good too.
      I believe he means using the dead drive in the headstock end, with a live center on the tailstock.

      OTOH, I've not turned anything since high school, so I could be way off base here. It's been known to happen.

      g.
      Smit

      "Be excellent to each other."
      Bill & Ted

      Comment


      • #4
        Originally posted by gsmittle View Post
        I believe he means using the dead drive in the headstock end, with a live center on the tailstock.

        OTOH, I've not turned anything since high school, so I could be way off base here. It's been known to happen.

        g.
        you've got it. He's using a dead drive in a drill chuck on the headstock and a live center on the tailstock.

        As he mentioned. PSI and others sell #2mt dead drives that would eliminate the drill chuck.
        Mike
        Lakota's Dad

        If at first you don't succeed, deny you were trying in the first place.

        Comment


        • #5
          Final_T,

          I don't have naptha here but I do have acetone, Denatured Alcohol and other dryers, but still I get separation at times. (Tried it.) I kinda wonder if even the imported woods that I get here is cured or dryed different than what is available in the States. The words "kiln dried" or other specific dried other than air dried have little use here. Microwaving doesn't help either. (BTW, their methodology for using green/air dried wood in construction is quite different than in the US, so kiln dried does not have a long history here.)

          While I get separation with cocobolo and CA occasionally, it is mostly with Japanese persimmon. It will shine up to a beautiful satin finish without anything but will dull quickly from there, showing finger smudges. So I prefer CA finish overall.

          On the dead drive, If I were back in the States, I would have purchased one there. They are cheap enough, but postage is more than twice the cost of the drive, if they will ship overseas.
          Hank Lee

          Experience is what you get when you don't get what you wanted!

          Comment


          • #6
            Hank, where can I get a "dead drive?" I looked it up at Woodcraft.com and PSI's website but they didn't return anything.

            Also, from what I understand, you do the actual turning with the mandrel and bushings, then take it apart and finish with this set up, right?

            Thanks.

            Anna

            Comment


            • #7
              Originally posted by Anna View Post
              Hank, where can I get a "dead drive?" I looked it up at Woodcraft.com and PSI's website but they didn't return anything.

              Also, from what I understand, you do the actual turning with the mandrel and bushings, then take it apart and finish with this set up, right?
              Thanks.
              Anna
              Here are two places to get the dead center, which by the way is sometimes called "Revolving Centers" but when they have those names, the price is 3 to 5 times as much!

              Precision ground 60 Carbide Tipped Lathe Center remains sharp and accurate long after other dead centers wear out.

              Get accuracy in your mini lathe with this 2MT dead center. Compatible with various mini lathe manufacturers, the Morse taper dead center is easy to install.


              You are right, I take it off the mandrel after turning and see how close the fit is in some cases (where it is easy to take apart), then move it to the dead drive. I may do some extra sanding from the dead drive but not turning.

              I believe that an experienced turner could turn from there, but it will take skill, patience and experience.

              To me, it is MUCH easier finishing that way. Bushings get into my way when I am finishing a pen.
              Last edited by leehljp; 07-25-2007, 02:09 AM.
              Hank Lee

              Experience is what you get when you don't get what you wanted!

              Comment


              • #8
                So can you sand/ etc with this as well? When I'm doing a light colored wood like yellowheart, I can get a grey coloration from the bushings. When that happens it's nearly impossible to get that crap out of the pores and it really hurts the look of the pen...

                Comment


                • #9
                  Originally posted by BigguyZ View Post
                  So can you sand/ etc with this as well? When I'm doing a light colored wood like yellowheart, I can get a grey coloration from the bushings. When that happens it's nearly impossible to get that crap out of the pores and it really hurts the look of the pen...
                  Yes, I did it today on a Churchill and didn't have a problem. Don't apply too much pressure from the sandpaper. I haven't so far, and I try to stay constantly aware of the pressure of the sandpaper on the blank with that set up.

                  That brings up something else: Having it tight enough on the end drives without over tightening from the tail stock. You can flair the tubes and break the wood if you don't watch.

                  One advantage is that the dead center and live center from the tail stock are angled. With the end of the blank being at 90 degrees to the center line, therefore creating a space of about 1/16 inch between the end of the blank and before the drive - at the wood level. I think that this can be a sufficient enough space to do a final sizing finishing from end to end and not touch the drive centers.

                  A hint that I used with bushings on light wood, I usually sand from the center outward to the ends with the lathe on its lowest or next to lowest speed. I personally try to get the blanks to as close as I can to the size that I want - with the chisel, and then with sandpaper, I start at the center and move outward; on the next stroke, I use a different section of the sandpaper about a 1/2 inch away. I have done that for the past year on lots of holly and didn't have a problem with it except that I use a little more sandpaper.

                  Another note: you will need to size the blank by using calipers once you are on the "no mandrel" set up. I always turn/sand my blanks down to around .005 to .008 smaller than the size of the nib, center ring or finial, and build that space back up with finish.
                  Last edited by leehljp; 07-25-2007, 08:03 AM.
                  Hank Lee

                  Experience is what you get when you don't get what you wanted!

                  Comment


                  • #10
                    Hank, thanks for the links. One last question: wouldn't replacing the bushings with smaller diameter bushings on the mandrel do pretty much the same job? That will also eliminate the problem with overtightening the tailstock and ease off the problem with sanding. I think.

                    Anna

                    Comment


                    • #11
                      Originally posted by Anna View Post
                      Hank, thanks for the links. One last question: wouldn't replacing the bushings with smaller diameter bushings on the mandrel do pretty much the same job? That will also eliminate the problem with overtightening the tailstock and ease off the problem with sanding. I think.

                      Anna
                      I think it would. But my primary reason was for the gluing. Even with waxing the bushings, a thick coating of CA on the blanks would separate in small spots when pulling the blanks off - specifically on oily blanks like ebonies, cocobolos and others.
                      Hank Lee

                      Experience is what you get when you don't get what you wanted!

                      Comment


                      • #12
                        Well I think I may try this. I can't seem to get a CA glue finish working for the life of me, but if I eventually do manage to do one I think this will help.

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                        • #13
                          So far I've got two (out of many pens) finished with CA that looks okay, but I can't remember how the heck I did it. Friend of mine described my finishing technique as a stochastic process. I thought that only applied to my cooking.

                          I'm going to give the mandrel-free turning a try when I get my new drive. Hope it wouldn't be too difficult to use it for sanding since that was my original problem too (metal dust getting into the wood pores).

                          Anna

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