Advice for Investment Casting of Gold, DIY Engagement Ring
I'd like to make my partner's engagement ring. It's something I've wanted to do for years, and hopefully you only get one chance, right?
I'm an engineer with a lot of tools, including a good workshop, dremel, microscope and a lot of experience making & designing things. But admittedly, no jewellery experience...
As much as I'd like to do the whole process myself, I think I'm going to take advantage of an online 3D printing and investment casting service, then finish the ring myself.
Maybe set the stone myself as well, but we'll have to see. Much advice needed here!
I've designed a prototype in CAD that I'd like to get some feedback on. Both the design, but also what allowances/tolerances I should design in for the casting?
Casting wise:
Any advice on the following would be much appreciated: minimum feature size, expected shrinkage, sprues, and design limits for what is possible with 3D-printed wax/resin casting. How oversized should I design the elements to allow for polishing losses?
I think I'll go for yellow 18k gold.
Does anybody know a good UK casting service that will print the pattern for me as well?
Design wise:
My partner doesn't like things too flashy, and I think she'll like what I've come up with, but maybe I'm missing things. Once I lock in a design, I might swap the circular prongs for D-shapes, or the front and back leaves for something flatter. The current stone is a 1 ct oval diamond.
Eventually, I think I might add a very small Euro shank to the base to help prevent it from spinning.
The prongs are very much a draft at the moment as I'm not sure where best to place them, 45 degrees or 55? Tulip tip ending OK or should the prong only be a longer single point right at the end?
There are some very tight spaces in the basket area, what is the best way to polish them after casting?
Is my split spiral design a crazy choice, or workable?