Friday, December 21, 2012

Wood Lathe -- Bowl Turning

So far in my wood lathe posts I have only described spindle turning. I do enjoy turning intricate shapes and designs into a long piece of wood chucked up between the spur drive and live center but that's not all that can be done with a wood lathe.  Here is a fine recessed rim bowl I turned from a solid slab of Mahogany.

To turn bowls requires a method called faceplate turning.  The stock can't be simply chucked up between two points like a spindle because one surface must be clear to allow access for the hollowing cuts.  In order to turn a bowl I use a device called a faceplate that supports the work piece fully from one side.  The face plate is attached to the wood blank by short wood screws and then the whole assembly is fixed to the threaded shaft of the headstock.
  

Here is the bowl and faceplate in position on the headstock.  I first prepare the workpiece by cutting it into a rough circle shape using a band saw.  Then I turn it round with gouges as if it were a giant spindle.  The majority of the hollowing out of the cavity is also done with regular gouges.  Simple salad bowl type turnings can be finished up completely with gouges and scrapers but the decorative recessed rim that I like requires a special tool to finish called a bowl scraper.
  
Because a standard gouge is shaped rather like a fingernail with the cutting edge out on the end the tool will only cut up to a certain point.  Eventually the angle of attack becomes too great and the side of the gouge will run into the top of the bowl rim.  The bowl scraper has a rounded button ground onto the end that greatly increases the radius of the tool's cutting edge allowing material to be removed from the underside of the rim.  This type of turning is the most challenging and is my favorite work on the lathe.  You can't see and are in essence cutting completely blind.  Feel for what's happening comes only with experience and feedback through the tool handle is all you have to go by. 
  

This piece is not finished yet. I have rubbed on a couple coats of tung oil but I still want to do some more sanding and additional coats of oil.  Once I'm satisfied I'll remove the bowl from the faceplate and fill the screw holes with a mixture of finely ground mahogany dust and wood glue.  When dried I'll use a palm sander and various grits of paper to make the bottom perfectly smooth and flat and then finish that surface with more oil.




6 comments:

  1. Wow! That's absolutely beautiful. It looks as if you've got a lot of woodworking experience under your belt.

    From start to finish, how long does it take to make something like this?

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  2. Love that rim. It was worth a special tool.

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  3. Hey thanks for the kind words! It takes probably 3 or 4 hours from start to finish. Carving out the shape usually goes pretty quick becuase I just get excited and can't stop until I reach the final form. Applying the oil only takes a few minutes for each coat but with letting it dry a day or two in between that process can go on for days if I want to do 8 or 10 applications.

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  4. Superb work....love the look of that a lot....
    Have a really good Christmas and New Year....

    -Trevor

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  5. Beautiful. Nice! Excellent, actually!

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  6. Very elegant shape Mike, it really sings. Tom,ab9nz

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