Egg cups with captive rings

egg cups

These egg cups were made for a client who likes captive rings. From left to right they are: apple, ash, laburnum, hornbeam and yew. Finished with friction polish and wax. Just in time for Easter! After the third one I was starting to get the hang of it, but the most nerve-wracking bit is detaching the ring.

The captive ring tools you buy tend to be shaped for a particular thickness of ring; I tend to prefer larger rings that don’t look like they’ve been milled. The tools I use I actually got second hand and are home made from bent masonry nails, one ground for the left side, the other for the right.

IMG_20160317_154140370I started with the inside of the egg cup, because that’s the shape that matters, and because that way there’s more wood to support it and keep it stable. I used a ‘reference egg’ made from a thin piece of wood and sized for a large egg, 47mm diameter, as specified. The flat shape allows me to check that it fits the cup without having to move the tool rest. The egg has to sit nicely without bottoming out. If the bowl got too wide, I simply took the top couple of millimetres off the rim and went deeper. At this stage I haven’t yet committed myself to where the base goes. I at least wanted all the egg cups to be the same height. Once I’m happy with the inside shape, I can then mark where the base is.

The next stage is to shape the outside of the bowl to a reasonably uniform thickness. The client wanted a thick stem, and the stem thickness is largely dependent on what it looks like when the ring comes away. It does look distinctly untidy, at that stage. I like to hold the ring out of the way with masking tape when I’m tidying the stem; many turners don’t bother on the grounds that the ring gets out of the way of its own accord but I still find it a distraction, especially with such a short stem.

You have to shape the ring and sand it before detaching it, but I did pick up a trick to sand the inside of the ring after it’s been detached. You just wrap sandpaper round the stem, hold it in place with tape, run the lathe slowly and hold the ring against the rotating sandpaper.

sanding captive ring

When it’s all sanded down to 400 grit, it can be sealed before parting off at the base. Reversing the cup to finish the base is always a challenge, and I’ve used my home-made wooden chuck jaws, which I don’t have a photo of to hand but will show in another post.

I then buffed the egg cups on a buffing wheel with buffing compound, followed by Chestnut WoodWax 22, which is toy safe and reasonably water resistant.