Mem-Gems with i.materialise technology

#1

Hi there,
I have developed a new laser projection jewelry technology called (Mem-Gems) that I think could be a perfect complement to i.materialise 3D printing and metal casting capabilities. Many of my early customers have asked for their Mem-Gems to be embedded in rings and pendants, and I have referred them to their local jewelers. However, I think that if I could have some design guidelines for them I am sure there would be a lot of interest, either in making them a ring with embedded Mem-Gem or guidelines for them to do it themselves.

I am planning to make my own wedding band with an embedded Mem-Gem as a proof of concept, so I will document my learnings along the way. So far, I have found that you are out of stock of white gold :frowning:
I will try regular 14k white gold. I want to embed the Mem-Gem with a “Gypsy” aka “flush” bezel set, which means some precision engineering on the embossed feature. I am planning to make my ring look like this:
reflection2

I have a degree in Mechanical Engineering, and am familiar with Solidworks and Autodesk Fusion 360 so I think I could probably pick up the software pretty quick. Any suggestions on which 3D software to use for the 3D design of a custom wedding ring that can house a Mem-Gem? Any other tips are much appreciated!

#2

Alright I got a design:

ring_assembly_2020-Nov-28_08-54-55PM-000_CustomizedView16472162691
ring_assembly_2020-Nov-28_08-54-55PM-000_CustomizedView164721626911518×701 73.5 KB

I will go with 14k yellow gold. I followed the design guidelines. However, I worry that there will be residual gold in the well post-polish, preventing the Mem-Gem from sitting nicely in the hole. I also worry about the dimensional shrinking. I would like the Mem-Gem to fit into the hole, and then use a burnisher to push the edges in afterwards to make a flush “gypsy” setting. I am planning to do a test print. What material is most representative of 14k yellow gold? Would silver, brass or bronze give a good representation of the gold part as a test or would they have different thermal shrink and resolution? Yes, I have read all the datasheets available on the i.materialise website, but I am missing the key information about typical dimensional shrinkage. I saw some posts saying 1.25% extra, others saying ±5% (crazy huge range!)

After a lot of reading and going through forums, I think I will just order one in silver and see how it looks. I hope that will be a good representation of what to expect on Gold.

#3

Hi arbutuspointtechnolo,
I’m still checking some questions with our production and will come back to you with a complete answer as soon as possible. In the mean time, I can already confirm to you that for i.materialise it’s not possible to predict what the shrinkage will be. A gold model is considered good as from the moment that the accuracy is within ±5% (with a lower limit of ±0.35 mm).
Please keep also in mind that we measure these tolerances on the outer dimensions of the entire part and we can’t guarantee that the Mem-gem will fit perfectly.
Kind regards Lizy

#4

Hi arbutuspointtechnolo,

Here I’m back with what I hope are the rest of the answers.

So, like I said before it’s impossible to predict shrinkage and a part is considered a good print the moment the outer dimensions are within the accuracy limits on our website (±5% with a lower limit of ±0.35 mm). The reason why there is such a huge range is because shrinkage is depending on the size of the piece (heat goes faster / slower).

Please keep in mind that to build your design when using these precious metals Wax 3D printing and lost wax casting are used and this can’t be compared to the accuracy of Selective laser melting (SLM).

We’re indeed still temporary out of stock of white gold due to the lack of palladium.

Production assured me that there will be little or no residual gold present in the cavity.

On your question about what material is most representative of 14k yellow gold, I’ve to tell you that there is no alternative with the same 14 kt properties due to different materials which are used to compose the other materials like silver, brass or bronze.

You also asked for a tip on which 3D software to use for the 3D design of a custom wedding ring that can house a Mem-Gem? Fo that please take a look at our blog https://i.materialise.com/blog/en/best-jewelry-3d-software/ where you can find out more which 3D modeling programs are perfect for jewelry designers who want to print their products in 3D.

So, I hope I covered all your questions. If not, please don’t hesitate to come back to us.

Kind regards

Lizy

#5

±5% seems like is a crazy high tolerance to me. I’ll measure my parts after the process to at least give others that might read this a mean value to aim for when their parts are a similar size to mine…

What about polishing? Is it possible to ask your staff to be careful around the hole and not round the edges too much? I don’t know if the polishing is manual or fully automated.

#6

Hello,

I can imagine that ±5% (with a lower limit of ±0.35 mm) seems like a crazy high tolerance to you, but when we’re talking about jewelry, we’re mostly talking about smaller parts and on a ring of 20 mm we are talking about a difference between 0.35 and 1 mm on the outer dimensions. This is due to the nature of the process (lost-wax casting and printing) used in the production of gold and there is nothing we can do about it.

Polishing is done manually and in order to polish, we have to be able to reach the surfaces. As a rule, we can’t file, sand or polish cavities and small sharp edges will be rounded off. Also, as you can imagine, complex internal, mesh-like structures are also impossible to reach.

Kind regards Lizy

#7

Hi, I know you were interested in white gold and wanted to let you know that we just got the message that this material is available again. Kind regards Lizy