One obstacle is the quality of the surface produced by standard Fused Deposition Material (FDM) of the popular plastic filament style 3D printers. FDM is getting good finish when printed at 0.2mm per layer or less. But not good enough for casting LWC model.
Another style of 3D printing using an Ultra Violet (UV) curing resin can produce layer heights as small as 0.025mm (25 microns) This is outstanding resolution. Several versions of this process exist. Some use a LASER beam to scan the layer. It's called Stereo Lithographic Apparatus (SLA). Another process uses a full layer exposure like a B&W negative for each layer. It's called a Digital Light Process (DLP)
Shown here is a Wanhao Duplicator 7 (WD7) I own. I bought it specifically for use in producing casting models. There are resins available that (should) burn out the same or nearly the same as wax in the Lost Wax Process. The key word is "should". More coming about that claim.
For more than several years I have been producing CAD models to produce programming to run my Computer Numeric Control (CNC) wax milling machine. A switch to producing Stereo Lithographic files (.STL) for 3D printing is a no brainier. The only difference is the output file created.
The first step in this new approach to lost wax casting is learning how to operate this new printer. It is totally different than my previous 3D printers. I have done some write up in my 3D Printing website. Here is the link:http://rd3dpds.com/resin-printer I have also posted some blogs on the subject: http://rd3dpds.com/blog
This article describes the outcome of this great experiment.
I have just completed my first casting of silver using the casting material from the WD7 printer. I was able, after some trial and error, to produce very decent quality 3D prints from the WD7. This printer works like a camera and film. The exposure for each layer of the print is critical to getting a sharp layer. The model I used here was as good a surface as I produce using wax carving. A good start. The printer is not a problem.
The issue I have discovered, is getting a clean burnout of the resin used to create the model. It is marketed as "castable resin". I followed the burn out schedule of time and temperature which is the same as I use for wax. The manufacturer claims very low ash, but does not state "no ash". Ash is the solid material left behind when all the volatile material is vaporized by high heat, 1350 degrees for 3 hours.
In the pictures can be seen the result of a non-clean burnout. This is a very disappointing result. This pendant (although I stamped my mark on it) is not of the quality I would offer for sale or as an example of my quality standard. The quality is very poor. It is the worst result I have ever cast. Of course all my other casts were made using wax masters.
At this point 3D printing is not going to be my go-to method for LWC. I will stay with WAX masters for the bulk of my work, thank-you...
I will continue to experiment and research casting resins. The 3D process will allow me to create models for LWC that can't be made by hand or CNC milling. That remains my goal. I am not going to let this failure be my only attempt. But I also don't want to stop doing my LWC until I get it working.
Right now I have a nice, but some what messy, very high resolution 3D printer. But I have a resin burn out that is very far from ideal.
The photography makes it look far worse than when I hold the pendant in my hand. It IS as bad as it looks, the camera doesn't lie.
I'll find a way to make this process work. I have spent enough time for now. The white residue from the alcohol wash may have contributed, but I doubt that. I'll try another resin cast the next time I have some wax masters to cast. I may need to try a more expensive castable resin. I have to admit this is the cheap stuff. It is also water soluble which was the initial attraction. Other resins require isopropyl Alcohol to clean up and dissolving of the resin residue.
There are other ways to skin this cat. The 3D printer can make hard models that are then used for making rubber molds that can be injected with wax. The wax is used for casting. The cost is material and another extra step.
Bottom line for me right now. The printer is certainly capable. The model material seems to be less than capable. It could be my technique. I have to decide if the time is worth the investment. I already get excellent cast product using wax. Being a pioneer with a new technique is hard work...
My last post was concerned SLA type 3D printing. There is a variation to the SLA laser beam where a full frame binary B&W image is projected at full frame for each layer of the print. Two variations of this process exist. One uses a video projector and the other puts the video LCD screen up against the resin tank with a bright UV light source behind the screen.
The process is called DLP (Digital Light Processing) and creates higher resolution 3D prints than SLA and can be done in some systems at much lower equipment cost.
This has changed my mind about the affordability of high resolution 3D printing in my world of dimensional art. I made a business decision.
I have a DLP 3D printer ordered. This new printer costs about the same as two of my FMD (plastic filament printers) That does fit within my budget.
The DLP printer can produce ready-for-investment masters for lost wax casting. That is my purpose for this printer. The full frame image permits printing multiple items at the same time and no increase in printing time. One ring or 20 copies all print in exactly the same time.
I chose a low cost simple machine. Not purposed for a high production rate but absolutely suitable for the scope and amount of work I produce. It will be a great learning tool. I will also be experienced to advise others or make upgrades in this first system.
Most of my reporting on this new tool will occur in my 3D printing website: http://rd3dpds.com. Eventually I’ll post more here, when I start producing dimensional cast items.
I have investigated this process for use in jewelry making and any other high surface finish 3D printing. The hardware cost has been coming down, but the cost of materials and the finish work such as UV hardening, and support removal are still cost and labor intensive. With enough production need the cost can be reasonable, but it is a system that should be utilized to its fullest extent.
That means it needs full time operation and not occasional utilization.
The process uses a focused laser beam (a) to “paint” the structure layer by layer, on a surface (c) immersed in a polymer solution (b). The light beam partially solidifies the polymer at the focus/surface point. The build platform (e) moves the item (d) away and usually out of the liquid polymer material as layers are added.
The results are usually the ability to produce a very fine, smooth, and accurate surface finish. Post curing and extensive support removal and detailing by hand are required.
Some of the polymer material is suitable for direct used for investing and casting. Other polymer material can be used in the vulcanized or cold process rubber mold making. Then wax burn-out masters can be produced. Many options are available for producing and using the final print output.
The process although high quality is still expensive and labor intensive. There must be a real purpose and plan to make full use of the technology. If everything I made originated in a CAD drawing, The process would be more attractive for the things I create. I would love a “free ride” to play with the process but to purchase such a system, it would have to pay its own way in increased sales.
I currently don’t produce enough jewelry items for SLA to replace my CNC machining. That’s bottom line reality.
I realize I haven’t posted here for a while. Mostly because I have a lot of other artsy/crafty blogs where I spend time. I like to think of those other areas as all one big happy family and this is a sibling of the others. Just different URL’s.
If I put or consolidate everything here for example, there would be just as much “stuff” and harder to stay on topic.
So anyway, I’m Back! The topic is Vectric CNC Software.
Most everything I create needs a 3D CAD drawing. That’s because I make a lot of things using 3D CNC subtractive machining and more recently 3D additive printing. That does not imply that I don’t do a lot of old fashion hand work or assembly of parts.
I have several powerful software options from which to choose. I write about the others as I continue to use them. My all-around favorite for 3D CAD and CAM is Vectric Aspire. I have every version of Aspire since it was first created. The newest version just released is Version 9.0. (Actually 9.008)
Originally Aspire was the combination of several other programs from Vectric and its strong heritage seemed to be toward the CNC overhead router, sign carving venue. That is a strong niche, but far from the only use and purpose for Aspire.
I use Aspire to design and carve wax masters for lost wax casting of jewelry items. An application almost never mentioned in their forums. It works very well for that purpose. I also use it for a lot of wood carving projects as well. Recently I have designed items for 3D printing as Aspire outputs very clean Stereolithography files (.STL). Again. A use not much mentioned in their forums.
I just pulled the trigger on the update from version 8.5 to 9 as there are some significant updates. They at last moved automated double-sided carving from their lower cost program Cut3D in to Aspire. Not 4 axis 3D, but “flip-over” 2-sided 3D. I am thinking a great feature for some pendant carving.
Purchasing the program outright, no upgrade, is a bit pricey at the $2K region. My upgrade was $400. However, I am making money from what I can design. So, the cost is easily justified. Some people may not want that level of expense in a hobby, but even hobby use can create a payback over time. It all about how much you use it.
There are individual programs at much lower cost. The Vectric moto is “Passionate About CNC” If that describes you, then you should be looking a Vectric CNC Software. Highly recommended by Dimensional Art Org.
I blew off the silver making for a while because of the 3D printing mania I just experienced. Yes, the 3D stuff can be very habitual, but in the end, it is just an unusual piece pf plastic. Not a durable piece of jewelry art cast in precious silver. Well, semi-precious silver.
I’ll remain somewhat engrossed with the printing as there are things worth making. I can always design special plastic things I need exactly to my specification rather than try to find readymade.
I just invested in a stock of new casting grain silver and a fresh box of investment plaster. I have some designs I know will sell. I like to make new designs more than remake what I have already done, but I don’t forget what my customers like.
I cast two new pieces just yesterday. I just love working with silver.
Silver doesn’t get wasted like plastic. Silver can be melted and used for something new. What is lost is the large effort required in making any LWC finished object. The cost of the silver is a small portion of the overall cost of material and effort.
I looked again at pen turning. I have made a few in the past. I could easily make wood (or other material) turned pens again. The barrels are the only part that are handmade. All the other parts are purchased. Some folks make these items as a full-time retirement occupation. The prices and profits are quite high for the effort involved.
I may make a few more examples since I have the tools and the material is easily obtainable. There is a huge business in selling the supplies. The pens (and other lathe turned items) are beautiful and unusual, but not the same creative art that stems from wax carving and producing art from totally raw materials.
I am not demeaning pen turners, they love what they do. I like to make them. The makers do add value turning and finishing the barrel, but most of the product is factory made parts that are assembled. It is what it is, a kit of parts. Value is in the mind of the buyer, looking at the finished results. ‘Nuff said.
Exploring new “making” opportunities is a great experience. Without the experience, I feel I have no right to comment or criticize ANY subject. Here’s a rule I try my best to follow; "Experience is the best teacher. Knowledge without experience is simply knowledge looking for application." It’s what “doing and making” are all about.