Router Plane

Monday, March 7, 2022

Wood Egg - #2 Completing the Turning, Finishing & a Problem

In this photo the turning has started and the right end of the blank has been brought down close to its finished size.  There is just a little more to be removed so the shadow line matches up with the pattern.  All of the turning here has been done with a fingernail ground spindle gouge shown in the bottom photo.

Here the bulk of the turning is done with just the ends holding the egg in the lathe to do.  At this point the tail stock gets pulled back out of the way so that the end can be turned to its final size and sanded smooth.

The top photo shows after the tailstock had been pulled back so the little nub/cone could be removed and after that nearly all the finish sanding done.  The bottom photo has the tailstock brought back up against the egg but with a folded-up paper towel added to provide a pad so the sanded end does not get scratched or damaged.  The tailstock is there to provide a little support while the left end of the egg gets turned.

Once the shadow from the wood egg lines up with the pattern on the shadow board the turning is complete except for a little bit on the end.  Rather than try to turn the egg off and risking a chance of it hitting the lathe or floor it gets cut free using a fine-toothed Japanese pull saw.  What little is left on the end is hand sanded to blend in.

The actual turning of the egg went pretty quick, probably around 45 minutes or so.  I am sure if I made a bunch of them it would get a lot less.  Since everything was set up I decided to make two more eggs.  In addition to the already completed cherry egg one of them will be from a highly figured piece of black walnut and the other will be from oak.  Here are the three completed eggs ready for finishing.  The cherry in the center is the first one.  The walnut egg on the left ended up just a tiny bit smaller as the blank wasn’t quite big enough in diameter to match it to the center cherry one.  The one on the right is out of oak.  Since that blank was larger it could be bigger – how about calling it a goose egg.  To revise the original pattern I just added a line about 1/8” larger than the original layout line and turned to it.

Normally my finish of choice is lacquer but here that’s a problem because there is no good way to support the piece while the finish dries.  The balls that I have made have a friction wax finish applied but that only works because the balls have a consistent diameter.  That allows me to rotate them in  the lathe about each of the X, Y and Z axis in a fixture to seamlessly blend the finish together.  This is not the case with an egg so I went with a three coat Danish Oil Finish. 

After the first coat the walnut and cherry eggs looked great but the oak egg’s proportions looked wrong.  At first, I couldn’t figure out why.  I doubled checked it against the pattern profile and it matched up just right.  For a day or so I couldn’t find a reason on why but then it dawned on me.  Because an egg is longer than it is wide or pretty much an elliptical shape adding a fixed amount to the perimeter distorts the length to diameter ratio making it look not quite right.  The fix is to change the current length to diameter ratio so it matches the original egg’s ratio.  I could do that by putting it back in the lathe and eyeball turning until it looks right or doing some math and laying out a new pattern based on the original egg’s ratio.  Since I already know from experience what happens when I try to turn the shape by eye the mathematical method seemed to be the way to go.  That change was not a lot, only about 1/16” needed to be taken off the radius or 1/8” off the total diameter at the widest point.  From there it's tapered toward the ends to blend in.  To see if my math was correct, I laid out the new pattern on the shadow board then put the egg back in the lathe and turned it down to that line.  After some hand sanding to blend things together it ended up looking like the other two eggs.  Here are all three eggs with the completed Danish Oil Finish.

I have to say there is not really any functional use in these turnings but it was a fun little project the does not take much material and I had plenty of available scraps to use.  Who knows if I get bored in the future I might try and turn more?  Maybe even an ostrich egg.

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