Ad Widget

Collapse

Announcement

Collapse
No announcement yet.

I need a better way to hold the bobbin

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Originally posted by David Schwab View Post
    I don't disagree, but my Schatten has an aluminum bar that was obviously not machined any further than having a couple of holes drilled in it, and it runs nice and true.
    Schatten has the machine tool to make the hole axis perpendicular to the faces of the bar. A good drill press will do this, as will a vertical mill used for drilling. Without a machine (such as using a handheld drill), it's hopeless.

    That said, your suspicions of the wooden spacer are probably justified.

    In any event, the OP should get a properly machined winder plate. The George Stevens winder is a tank, and with a good faceplate things will go far better.

    At normal winding speeds, one cannot really tell what's going on, and mystifying things happen. One thing I found helpful was to provide a recess into which the bobbin flanges fit, so the wire physically cannot hang up on the edges of the bobbin flanges. This can be as simple as an aluminum plate roughly the same thickness as the bobbin flanges with an bobbin-shaped oblong hole cut in the center. The fit need not be precise, and there can be a gap between bobbin and plate. The plate is held to the faceplate with a few countersunk screws. But, sand everything smooth so there is nowhere for the wire to catch.

    Comment


    • #17
      As a followup to the original topic, here are pictures of the face plate that I made up for Nate (888guitars). It's 4" diameter, turned from a slug of 6061 aluminum. The hub on the back is 1" diameter, and the bore is drilled & reamed to 0.376" to fit a 3/8" shaft. Two 10-32 setscrews lock it on. The flange is 3/8" thick. Nate asked for the milled groove on the face for magnet clearance when he does reverse winds. There's a single 4-40 tapped hole in the center. I added a 3 degree bevel around the outer edge of the face and gave it a light polish to help prevent wire snagging.

      I charged him $75, and it took me about 2 1/2 hours to make. No big money maker job for me, but I'll make up custom face plates like this for any of you guys who need them. Let me know.
      Attached Files

      Comment


      • #18
        I've taken my wobbly faceplate (an aluminum rectangle) and mounted a dial indicator in front of it to measure the how off axis it was and then shimmed one side until it was in plane. I used electrical tape as a shim and got it pretty bang on.

        Comment


        • #19
          Originally posted by Bruce Johnson View Post
          As a followup to the original topic, here are pictures of the face plate that I made up for Nate (888guitars)...
          Nice job! I think I'll have to enlist your services when I start getting my new winder together.
          It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein


          http://coneyislandguitars.com
          www.soundcloud.com/davidravenmoon

          Comment


          • #20
            An extra note:
            I can also help you if you need other machined parts for your winder. Here's a driveline kit that I made up for another customer, with an aluminum face plate, a stainless shaft, and matched timing pulleys and belt.

            As I said above, I offer these services to other winders because I have the machinery to do it, and I know that it can be hard to find a machine shop willing to work with you on little jobs. I quote jobs like this at about $25/hr, whereas my normal rate for machine work is $45/hr.

            Hmmmm......Well, under the new, improved format, I can't seem to figure out how to upload an image from my computer. Under Manage Attachments, it seems like the only option is to upload from a URL. Is that true?

            Okay, thanks David! I think I got it now.....
            Attached Files
            Last edited by Bruce Johnson; 06-12-2010, 12:18 AM.

            Comment


            • #21
              Originally posted by Bruce Johnson View Post
              An extra note:
              I can also help you if you need other machined parts for your winder. Here's a driveline kit that I made up for another customer, with an aluminum face plate, a stainless shaft, and matched timing pulleys and belt.

              As I said above, I offer these services to other winders because I have the machinery to do it, and I know that it can be hard to find a machine shop willing to work with you on little jobs. I quote jobs like this at about $25/hr, whereas my normal rate for machine work is $45/hr.
              Cool!

              Hmmmm......Well, under the new, improved format, I can't seem to figure out how to upload an image from my computer. Under Manage Attachments, it seems like the only option is to upload from a URL. Is that true?
              I had a hard time finding it the first time as well. It was showing previous uploads.

              In the upper right hand corner is a button labeled "Add Files", click on that.

              Then click on the "Choose Files" button and browse to your file.

              Then press "Upload"

              Then you will see it in the "Attachments" pane at the bottom.

              Check the box next to the image then choose Insert Attachment or Insert Inline.

              The old attachment window was much easier.

              Click image for larger version

Name:	SafariScreenSnapz002.jpg
Views:	1
Size:	170.3 KB
ID:	818598
              It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein


              http://coneyislandguitars.com
              www.soundcloud.com/davidravenmoon

              Comment


              • #22
                Originally posted by Bruce Johnson View Post
                As a followup to the original topic, here are pictures of the face plate that I made up for Nate (888guitars). It's 4" diameter, turned from a slug of 6061 aluminum. The hub on the back is 1" diameter, and the bore is drilled & reamed to 0.376" to fit a 3/8" shaft. Two 10-32 setscrews lock it on. ...
                One improvement occurs to me while looking at the photos. I would have put the two setscrews 45 degrees apart, not 180 degrees apart, for greater stability on shafts that are not a perfect fit in the hub bore.

                Comment


                • #23
                  Originally posted by Bruce Johnson View Post
                  Okay, thanks David! I think I got it now.....
                  You did indeed!

                  Nice looking parts. Now I have to start designing my winder so I can use your services. You know the old saying * , "I could rule the world, if I could only get the parts..."

                  (*also an album by the Waitresses)
                  It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein


                  http://coneyislandguitars.com
                  www.soundcloud.com/davidravenmoon

                  Comment


                  • #24
                    Originally posted by Joe Gwinn View Post
                    One improvement occurs to me while looking at the photos. I would have put the two setscrews 45 degrees apart, not 180 degrees apart, for greater stability on shafts that are not a perfect fit in the hub bore.
                    Joe, I usually use two setscrews at 180 just to keep it balanced to minimize vibration. A trivial thing, just an old habit. The clearance on the shaft should be 0.001" unless the shaft on his machine has been chewed up somehow.

                    Comment


                    • #25
                      Originally posted by David Schwab View Post
                      You did indeed!

                      Nice looking parts. Now I have to start designing my winder so I can use your services. You know the old saying * , "I could rule the world, if I could only get the parts..."

                      (*also an album by the Waitresses)
                      Thanks, David. That's why I keep aquiring machines. Every new machine tool gives me the capability to make parts the way I really want them to be, when I need them. So I can build even more machines. It's a difficult addiction to kick.

                      Comment


                      • #26
                        Originally posted by Bruce Johnson View Post
                        Joe, I usually use two setscrews at 180 just to keep it balanced to minimize vibration. A trivial thing, just an old habit. The clearance on the shaft should be 0.001" unless the shaft on his machine has been chewed up somehow.
                        I've never seen 180-degree separation used except when needed for lateral adjustment, rather than simply to affix a hub to a shaft. Nor are all shafts perfect.

                        The setscrews don't weigh very much and are very close to the axis of rotation, so dynamic balance won't be affected. More to the point, the only thing that will matter in practice is to get the center bore and the rim of the face plate concentric, because the effect of a small test mass of constant size varies as the square of distance from the rotation axis. Sufficient concentricity is almost automatic if one turned and bored on a lathe without removing the faceplate from the lathe.

                        Anyway, a pair of setscrews spaced 45 degrees apart was good enough to get a patent, now expired, because of far greater rigidity and resistance to loosening (because the parts were far less able to wiggle and work themselves loose). (No, I don't recall the patent number -- it's been a long time.) Lots of people used 90 degree spacing, which does work, but 45 degrees worked surprisingly better, according the trade press of the day. Not that it will be so critical for a pickup winder, and I bet 60 degrees will work just as well.


                        On something this small, it won't be important, but on larger stuff it is standard practice to ensure that the setscrews don't stick out, for safety. Those oldtime big square-headed setscrews were a big danger as they tended to catch clothing and pull people into the gear works, causing the gears to rust.

                        Comment


                        • #27
                          I have to say that all the high end knobs I have two set screws at 45 degrees apart.
                          It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure. — Albert Einstein


                          http://coneyislandguitars.com
                          www.soundcloud.com/davidravenmoon

                          Comment


                          • #28
                            Originally posted by David Schwab View Post
                            I have to say that all the high end knobs I have two set screws at 45 degrees apart.
                            Hmm. I didn't know that, but it makes sense, as control shafts are not made to particularly tight tolerances.

                            Comment


                            • #29
                              Originally posted by Bruce Johnson View Post
                              ... Nate asked for the milled groove on the face for magnet clearance when he does reverse winds. There's a single 4-40 tapped hole in the center. I added a 3 degree bevel around the outer edge of the face and gave it a light polish to help prevent wire snagging...
                              Wow, like minds and all that!.

                              Here is one I had made for my second winder, I have the same magnet clearance slots (one for single coils and one for humbuckers stud-coils) and the 4-40 in the center.

                              (the axle shaft actually has the 4-40 hole)
                              Attached Files
                              -Brad

                              ClassicAmplification.com

                              Comment


                              • #30
                                How much is that kit?

                                Originally posted by Bruce Johnson View Post
                                ...Here's a driveline kit that I made up for another customer, with an aluminum face plate, a stainless shaft, and matched timing pulleys and belt......
                                -Brad

                                ClassicAmplification.com

                                Comment

                                Working...
                                X