Didn't want to pinch Richard's thread, and Tom asked about somefink I mentioned in it.
Find a hole saw, piece of steel pipe, bike handle bars, anything like that. If a saw gently grind the teeth off so as you end up with a flat end to the pipe. Do the same with all pipes, grind a flat end. Then carefully grind around the outer edge so you are forming a bevel around the edge. Your are not forming a cutting edge, what you are looking for is to form a small burr around the edge.
When you use these you only use then on a bigger ball than the inner diameter of the pipe. You DON'T want the pipe to slip over the work. Also either make a wooden handle for the cutter, or at least wrap the holding end in a rag and masking tape to protect your hand.
To make a wooden ball of say 50mm diameter, Take a piece of wood at least 65mm long, mount between centres and rough down to approx. 51mm. Mark a middle pencil line and turn a ball shape from the line, turn until you are left with a short stub on each end, and a ball shape. Just make sure you don't under cut below the 51mm on the horizontal as well. These sizes are not critical, just approx.
Now take a pipe approx 45mm dia and press it against the ball shape, while moving the cutter all around the form. Almost as if yo are rotating the pipe all around. Keep watching and once the whole surface shows to have been scraped you now have a perfect sphere. Take off the lathe and using a saw remove as much of the stubs as you can.
To finish, make a wooden end for your live centre with a slight hollow end on it, put a piece of wood in the chuck and turn a hollow in that which fits the dia. of the ball. Mount the ball between these wooden ends so the stubs are revolving on the vertical centre line. Protect the ball with tissue of router mat when you mount.
Switch on and you will now see the ghost of the stubs as the lathe revolves. Turn down gently using a spindle gouge, and sand. Or if you want to be perfect you can gently use the pipe once more after you have taken most of the stubs away.
Hope you can understand all this, it's far too early in the morning for me. Just make sure that the the piece of pipe you use is of a smaller diameter than the diameter of the ball you are making.
Find a hole saw, piece of steel pipe, bike handle bars, anything like that. If a saw gently grind the teeth off so as you end up with a flat end to the pipe. Do the same with all pipes, grind a flat end. Then carefully grind around the outer edge so you are forming a bevel around the edge. Your are not forming a cutting edge, what you are looking for is to form a small burr around the edge.
When you use these you only use then on a bigger ball than the inner diameter of the pipe. You DON'T want the pipe to slip over the work. Also either make a wooden handle for the cutter, or at least wrap the holding end in a rag and masking tape to protect your hand.
To make a wooden ball of say 50mm diameter, Take a piece of wood at least 65mm long, mount between centres and rough down to approx. 51mm. Mark a middle pencil line and turn a ball shape from the line, turn until you are left with a short stub on each end, and a ball shape. Just make sure you don't under cut below the 51mm on the horizontal as well. These sizes are not critical, just approx.
Now take a pipe approx 45mm dia and press it against the ball shape, while moving the cutter all around the form. Almost as if yo are rotating the pipe all around. Keep watching and once the whole surface shows to have been scraped you now have a perfect sphere. Take off the lathe and using a saw remove as much of the stubs as you can.
To finish, make a wooden end for your live centre with a slight hollow end on it, put a piece of wood in the chuck and turn a hollow in that which fits the dia. of the ball. Mount the ball between these wooden ends so the stubs are revolving on the vertical centre line. Protect the ball with tissue of router mat when you mount.
Switch on and you will now see the ghost of the stubs as the lathe revolves. Turn down gently using a spindle gouge, and sand. Or if you want to be perfect you can gently use the pipe once more after you have taken most of the stubs away.
Hope you can understand all this, it's far too early in the morning for me. Just make sure that the the piece of pipe you use is of a smaller diameter than the diameter of the ball you are making.
