Replies

1. 
   dgreen | Sep 08, 2007 08:51pm | #1

   I use a pencil compass to draw a ring on the faceplate. Once you have a ring drawn it is quick and accurate to locate the corners of your work within the ring.

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   It would indeed be a tragedy if the history of the human race proved to be nothing more than the story of an ape playing with a box of matches on a petrol dump. ~David Ormsby Gore

1. 
   vwalla | Sep 08, 2007 08:59pm | #2

   Unfortunatley my work piece is about 11 inches & the face plate is 6" (approx).  I would not be able to see the drawn ring.  Also the face plate has radiused corners so when setting flat, it is hard to guage the palcement of the plate on the work piece.

    

   Thanks

1. 
   dgreen | Sep 08, 2007 09:24pm | #3

   Can you draw a centerline on the faceplate and extend it over the sides? Then just line it up with the centerline of your work.------------------------------------

   It would indeed be a tragedy if the history of the human race proved to be nothing more than the story of an ape playing with a box of matches on a petrol dump. ~David Ormsby Gore

2. 
   oldusty | Sep 09, 2007 01:27am | #8

   vw,

           You say the face plate is 6" and the work piece is 11" , could you find the center of the backside of the work piece and with a compass draw a 6" or a size that allows you to clearly center the face plate to the wood , then attach it ?

        First ,  Spin the face plate empty and check to make sure the O.D. is concentric with the mounting threads into the head stock  .

                    dusty

   Edited 9/9/2007 12:50 am ET by oldusty

1. 
   SteveSchoene | Sep 09, 2007 05:08am | #9

   I'd say Dusty has given you good advice. 

1. 
   vwalla | Sep 09, 2007 08:33pm | #10

   True...but I think that the face plate is not concentric.

   I made a large disc awhile back that I forgot about that is perfectly true (3/4 ply wood about 12" dia).  I use it for sticking sanding discs to it.  I think I can find the dead ctr of that & utilize some of the techniques presented.

   Thanks for all the advice.  I will post pics of what I have done...prob a concolmeration of a few posts here.

   Thx,

   V

2. 
   oldusty | Sep 10, 2007 12:16am | #11

   V ,   since you have metal cutting bits and tools you could check and true the face plate while it is spinning on your wood lathe , then it would be concentric .

          My guess is it's not off by much if at all , the accuracy you can expect with wood can be found on a tape measure , smaller than that may be an unrealistic expectation of the medium , imo .

              dusty

2. 
   jako17 | Sep 08, 2007 09:40pm | #4

   Spindle turn a short dowel that is a slip fit in the 1 in threads bore it on the lathe to fit a pencil that is sharpened  concentrically and use that to mark the centre.I assume that you have dimpled the workpiece with a punch first to enable you to feel it with the pencil point.Essentially that is the same as you will pay a machinest to do

3. 
   Steinmetz | Sep 08, 2007 09:49pm | #5

   Don't use threaded rod (It is notoriously inaccurate)

   Rather, have the centering fixture turned to exactly fit your plate's thread .
   Have the device turned from hex stock,so a wrench can 'snug' it into the plate.
   Also,taper it's point so (when fitted)it slightly extends from the faceplate. Also, most face plates are not concentric at the outer diameter.
   Have them turn off a bit of the radius, so as to present an accurate concentric edge for locating the work piece/pieces to your 'drawn ring'

   Steinmetz.

   
   

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   Edited 9/8/2007 2:53 pm ET by Steinmetz

4. 
   Napie | Sep 08, 2007 10:25pm | #6

   Make a single screw center plate out of a piece of 3/4” plywood and a sheet metal screw that will be attached to your existing faceplate.  Fasten it to your faceplate; put it on the lathe and center it all up including drilling a pilot hole for the sheet metal screw with the tail stock.  It is far easier to use and has only one screw hole to deal with on the finished work.  They are simple to make and hold just as well due to friction on the plywood as using all of those screws in the other plate. And it is useful for any large faceplate type work, in fact you can make a lot of them for different sizes..

1. 
   vwalla | Sep 09, 2007 01:12am | #7

   I think that I am going to have my shop machine out a pointed piece for me (for free as I own the company).  We use PD material, so I am going to have them CNC a point on our lathe then roll the threads.  I will post back the results.

   Thanks for all your comments.

   V