Making Our Wedding Rings

So I always planned on making my own wedding rings, so when I asked Cheryl to marry me it was time to make it happen.  I did some sketched on paper of things that I thought wouldn’t be too hard to make.  After we decided on a basic design I decided to machine the rings our of acrylic.

First Cut on Acrylic Rod

Then I turned it to the correct outer diameter.

Turning the Outer Diameter

Then I used a hand ground profiling tool to form the outer shape.

Forming the Outer Radius

For my ring I then turned a simple groove on the outside.

turning_the_outer_groove

I bored it out, shaped it a bit, added a wax sprue and it was ready to be invested.

Plastic ring with wax sprue in flask

Cheryl’s ring was a bit more complicated.  I did a CAD drawing of the ring, and wrote up the deg increments I’d have to rotate it to put in each of the dimples.

CAD Drawing of Cheryl's Ring

I set it up on my Sherline Mill with the rotary table to do the precise rotation.

Sherline Mill setup

And after doing a few practice runs I was off and drilling the ring blank.

Drilling Holes in Cheryl's Ring
I then bored out the inner diameter of the ring.

Boring Inside of Ring
Then just like the other ring I added a wax sprue, and it was ready to invest.

Cheryl's Ring with Wax Sprue
I mixed up some investment, and used the vacuumed pump to draw out the bubbles.

The Vacuum Setup
Here you can see the investment bubbling.

Investment  Bubbling

Once it had hardened around the rings the flasks looked like this.  The dimple is formed by that black rubber cap that you saw in the other pics, and now only the red wax sprue is visible.

Flask Before Burnout
Then I burnt them out in this kiln.
My Kiln before Burnout

I was originally going to use my home brew electric spin caster to cast this, but I didn’t have 24v worth of heavy duty batteries, and my beefy 24v supply wasn’t up to the task, so suddenly I had to improvise.  Thankfully I knew I had an old mechanical spin caster in a box (that I’d picked up at a garage sale).   I dug it out, screwed it to the floor of the shop, and cast the rings without any sort of nice safety barrier making sure I wasn’t about to spin a lot of molten silver all around the shop.

spin_casting_machine

At this point the inside of the rings is mostly cylindrical, with a bit of a rounded edge.  I wanted more of a “comfort curve” kind of shape, so I did that by hand with a sanding drum. I made a number of acrylic jigs so I could polish/clean up the rings on the lathe.

Shaping the inside of the ring

After a bit of chemical darkening, and clean up the rings were done.  (They’re silver, but the red sheet makes them look a bit like gold.  Oops.)
both_rings_on_red