Trying to think of a cool Christmas thyme project, the thought of colored glass enamel came to mind. Of course! Color is what is needed and missing in my silver work. I use a bit of black silver oxide on many of my pieces for definition. But there is a universe of color available.
The process in this project is called champlevé. I don’t carve the troughs for the color but rather use a lost wax silver casting with the recesses designed into the casting.
The vitreous enamel pundits say glass enamel can’t be done with Sterling silver (because of the copper) but as can be seen, it’s all just knowing how.
The process is to pickle the silver and create a barrier layer of pure silver on the surface. I may explain the process in some future post. It’s not magic, just a technique.
There is a similar process to champlevé called basse-taille. The difference is basse-taille used transparent enamel so features and designs under the enamel can be seen. That will be on my agenda for some future project.
This is a Christmas season pendant, so I picked a poinsettia blossom as my subject. I found a general outline drawing of a poinsettia so I would get the shape correct. It was not in a useable format for designing a Champlevé but got me started in my own design.
The pendant was created in Vectric Aspire (V10) as I am very comfortable with designing with this software.
Since Aspire can output .stl files, after I completed the design, I used one of my 3D printers to create a plastic prototype. The real output was to a g-code file for my Taig CNC mill.
I have one of my Taig mills dedicated to carving wax. I modified this mill by adding a 20.000 rpm water cooled spindle and a fourth axis (A) for rotary milling projects. (jewelry rings).
I machined two wax masters of the poinsettia pendant design and cast them in sterling silver using the lost wax casting method.
The resultant casting was cleaned and prepped for the champlevé process. Four firings (layers) were required to fill the recesses.
After the enameling was complete, the silver was again brought up to a full mirror like finish, through several stages of polishing.
Last step was the addition of the bails.
I think they look quite good and now I am planning to make a few more duplicates, then move on to other glass enameling projects.
A common human desire is to have a personal sense of value. A purpose in life. There is no one answer for what that requires or how it is achieved. Value probably has an infinite number of manifestations. It can be tangible or intangible (emotional).
I have no internal struggle with my sense of value. I am generally comfortable with who I am and what I have done. I do ask myself the “what value?” question when making more than minor decisions. Major decisions are judged on the value it creates.
I try my best to stay on the positive side of the value judgement. I may not always make the “right” decision. When I don’t, I call it a learning experience.
My current life goal is to spend time on being creative and making quality “craft” items that will be my “having lived” legacy for family and friends. Those items need to be of sufficient “value” to endure the test of time. The value can either be emotional or tangible.
I set course a couple of years ago to explore a new “making” system, commonly called three-dimensional printing. At the hobby level, it soon became a major part of my time and effort. It is a very fascinating process to master. I have mastered the process and have made (printed) a considerable number of things.
But I soon realized, most of what I make in on the junk (Junque) side of the value curve. That’s the lowest end of the scale…
I have produced items of value which are accessories to other creative processes and tools that I use. Holders for my wax carving tools for example. Not going to itemize them all but certainly valuable to me. Just not items to be cherished keepsakes.
Three-dimensional printing has proved considerable value in refining my CAD (drawing) skills. But very little value in the Items I have been making. The output material is PLASTIC. Therein lies the quality and value issue.
There is a lot of WOW! value because it is a new high tech process. But the same item made from conventional materials have far more intrinsic value. So, 3D printing has a definite place in my skill set. Just not in producing high quality and valuable heirloom class items.
Decision time. A time to refocus on how and where I spend and create items of quality. 3D printing remains a useful tool. It’s not going away. But…
My focus and time will return to making high value items with conventional materials like wood and metal. Automated machinery including 3D printing is certainly part of the process.
Bottom line: A lost wax cast Sterling silver jewelry pendant far outclasses (more enduring value) than the same design in layered extruded plastic. Plastic is a great choice for the mundane items of everyday use. I see more intrinsic value when plastic is not the primary or sole material.
My wife, Gloria has her hobbies. The main one is certainly her quilting avocation. We could probably sleep every night of the year under a different quilt. Well, that might be an exaggeration, as I have never counted them, but she does have a passion for making lots of them. It's also a social gathering for her and her quilting buddies. They are all female, but there is no reason a male couldn't enjoy this sewing art as well.
The ladies gather in "retreats" where they spend a few days in secret hide-outs doing their sewing thing. As far as I know there are no men invited. :)
Gloria likes to give away some of my three dimensional printed objects as little gifts at these gatherings. The last item was a drink coaster with a quilting design called a square in a square in a square. Evey quilter knows that basic design pattern in their quilting work. I thought it was a good idea for a design quilters would recognize.
I designed a suitable coaster in Fusion 360 and was soon busy making a big pile of them (see pictures).
After the retreat, I was searching for ideas for creating a lost wax cast silver pendant design. There was an obvious conclusion. A pendant with the three nested squares is a perfect jewelry accessory for a quilter. It's a simple design and a recognizable symbol to them. It is also a good conversation topic starter to explain to a non-quilter what it represents.
Back to Fusion 360 and a new square drawing. The pendant needed to be small. I chose a one inch square as quilts are produced to inch measurement. The CAD drawing is metric though, because I intended to three dimensional print the master model. 3D printers almost exclusively use the metric measuring system for the materials as well as the print designs.
Being well practiced in both measurement systems, it is no issue to use either or both. It is the way it is today.
The bars in the design are designed to be 2 MM wide and the pendant is 3 MM thick (and 25.4 MM or 1 inch square).
I try very hard to use three dimensional printing with my silver work. It should be a natural fit, but there have been issues with the castable resin used to create the model. It has to burn out of the mold as clean as the standard wax model. That has been a very long learning path. It does work when all the production methods and secrets are known, and a rigorous process strictly followed. That's a story told in previous posts.
I will continue with both wax carving and 3D prints for my silver work. Each has it place.
I produced the green plastic example as a proof of concept to show my "boss" (Gloria). It was quickly produced on a FDM fllament type printer. It is a low resolution prototype.
Resin DLP 3D printing (by UV light) requires a lot of design effort in supporting the model for printing. Not necessary for FDM printing and the reason for doing the FDM print first.
AS it turned out, the first DLP print was what I can only call a disaster. My supports were inadequate and only one resin pendant survived. As I said above, resin printing is a bit of a challenge to get right. A re-think and a re-design of my supports and I was able to produce three high quality resin master models on the next try.
The printing is the first step. It is working well now that I have the correct resin and I don't make poor support designs. The really big issue has been getting clean cast silver from the burnout. Many of the resins tried and the process variables (trade secrets) are incorrect for the low cost equipment used by me and most other low volume craftspeople. But as you can see, it can be done. Much learning by failure is required as what doesn't work becomes a learning experience.
Happy days are here and the silver pendants are examples that printing master models will continue at KautzCraft.The pictures tell the story.
I have succeeded in producing a fairly good cast ring from a 3D print master model. This came after many failed and unsatisfactory attempts. There have been numerous issues but the hardest one to overcome has been the failure of the investment during the model burnout. The resin from the model apparently doesn't totally cure. Especially in a thick section model. The uncured resin combines with or attacks the gypsum in the investment during the investment cure and subsequent burn-out.
I found a written article published over two years ago that confirmed every one of my suspicions. A jeweler in Bellingham, Washington, Jim Binnion (https://mokume-gane.com/about/jim-binnion/) offered a solution. It involves high vacuum curing the model in a heated oven, after ultrasonically cleaning it in water, fresh off the printer. No alcohol is used on the model and a UV cure isn't necessary either.
Jim is a professional jeweler and has professional grade equipment. I assembled a hobbyist grade equivalent, seen in the following pictures. I can't get or measure the 10 micron vacuum Jim recommends. I did notice the vacuum stop at one level, then about an hour later it dropped anotherl .5 inch WC. An indication there was gassing off of the tiny model, which created the drop in negative chamber pressure. I was heating the chamber to 180 degrees Fahrenheit. There was also some condensation (resin?) on the clear and cool lid of the chamber during the vacuum operation.
This ring is one of my best 3D printed casts so far. So, it looks like Jim's information about using a vacuum was good and I am on the right track to good casting. I will continue using this method. I have also resigned myself to keep the model section as thin as possible. The thicker the model the harder it is to properly cure.
That’s Three Dimensional Printing. My first attempt with resin material was not satisfactory. I posted the sad results HERE. However, one attempt does not qualify as a final result. Successful people keep trying what they want to do until they get it right. In this case, find the combination that works. Thomas Edison once said he discovered hundreds of ways not to make a light bulb.oweverH
Luckily, I didn’t have to go that far. There are people other than myself already doing it correctly. The materials for a successful 3D print casting exist. It just a case of sorting out all the variables and putting them together in a production stream that works for my conditions and situation. That’s what I enjoy. Working out the details of a very complex process.
The 3D plastic still doesn’t burn out as well as wax. I continue to see evidence of ash or debris on the resin castings. Not as bad as my first test. The PLA burned out quite well. The results are useable but not as good as I can cast with wax masters. Next run I will extend the 1350F hold from two to three hours.
The "wiggly" thingy was hand carved wax. The Fleuer-de-cross is resin DLP and the ring is PLA via FDM printing.
The new Plasticast investment powder is a wonderful product. It will be my new preferred investment powder for use with wax as well as plastic. The vacuum de-airing was a bit frightening. It rises over twice the height of my previous powder. I mentioned this in my previous post. Mold release (water quench) is outstanding. I love when a plan comes together, and things start working the way intended. It opens the door to making 3D printing a part of the LWC process and I have a new ability to design and create.
I am not at the point where 3D printing is going to be the only way I create models. Wax carving by CNC milling and hand is not going to go away. I enjoy the manual carving. The “squiggly” pendant is an example. It was completely hand carved. I enjoyed making every curve with files and wax carving knives.
The investment process brings out EVERY minute detail in the model. It hides NOTHING. The 3D prints, especially the FDM with PLA shows every layer line in the model. My first instructor warned me, it is far easier to smooth and detail flaws on the model, than to remove those flaws from the silver casting. How true that is!
I was able to grind and polish out the slight “evidence” of the FDM layers, but that’s doing it the hard way. Resin 3D prints are much smoother, but not perfect. Wax is still the best material for masters but can be fragile to handle. Everything has a compromise to understand and consider.
I may have a use for FDM 3D prints now that I know the PLA can be burned out. I may want that look. I am now feeling better about doing design with my DLP (Wanhao D7) printer.
Full STEAM ahead. (I like model steam engines, too) I am already getting requests for jewelry that can be designed in CAD, 3D printed, and cast is silver!