seeking collaborators for a metal cast printer system

I have been interested in metals printers for many years now and have written a lot on the reprap wiki. I am looking for people especially in totonto to collaborate with on making some progress, probably with with either the hacklab or there a place called 160 bartley we could work from, unless we can find a garage.

There is an entry on the wiki and previous interest expressed on producing a 3d metal printer. I myself have been interested for way too long, years in fact. I should say now that coming from mechanical engineering land and milling that I see good material properties -low internal stresses, full or nearly full strength- and dimensional accuracy - measured in terms of deviation from the initial computer model and including surface smoothness - of the output object, as critical to making the project worthwhile.

But given the impact of the reprap, even a humble metal printer should be really really interesting. Upon extensive reading over years I think the most practical concept I have been able to either think of or find in terms of reasonable doability and also quality output is a mini version of the Shape Deposition Modelling process that some people at iirc cornell have been publishing on, to produce a zirconia mold which can be used to cast a steel object.

Premium investment casting I have seen advertised as being accurate to 80 microns over 2 centimeters, but that is with 3d stereolithography printed master, from which a mould is made and then wax patterns with it, then finally ceramic is deposited on the wax the wax removed and steel poured. So an extra three steps to loose accuracy across. Hopefully we can do better than that easily therefore.

In this case with a build material of ceramic of the type widely used in steel casting, which is zirconia flour mixed with zirconia colloidal sized particles and some other particles to adjust the coefficient of thermal expansion sometimes. They are mixed with water and then the water evaporated to leave a low stress solid layer. The strengths are typically 2000 psi according to some patents I have read although I could do with another look at those.

The support material some kind of wax perhaps. There are zero shrinkage machineable waxes available for dental use etc.

During the build process there is basically no air in the layers that have been put down, all void space is filled with one material or another.

I won't try to spend forever writing a magnum opus on my phone to describe the process here because it is easy to google although that is on my list of things to do. Basically you deposit material pretty crudely then mill it to the desired shape, and repeat. This saves you from the difficulty of depositing material in an accurate way.

Like with laser sintering the geometries here are essentially whatever you can draw on the computer, limited in the size of the features by the size of the end mill in this case though, and no hollow objects.

I know very little about this field; but I wonder whether it would be possible to print a hollow version of the model in wax, then use the final stages of the traditional lost wax process to cast it in bronze?

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Is this different than just using PLA instead of wax?

Can you use PLA for this? Does it burn away as cleanly as wax does? This isn't my area of expertise.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

31. Has anyone used a 3D printed plastic part as a mould master, in a process akin to lost-wax casting?
Yes. See: Metal bits from a RepRap and Lost PLA Casting from 3D Prints

- from Read Before Posting - Technical Questions and Answers

Sigh. Yeah but I really want to go and produce a printer capable of good quality output. That will enable serious things for real people in a very substantial way .... well I will leave this thread here I guess, anyone who is willing to join me email anthony.a.douglas with the relevant domain name being gmail .

There's also machinable wax filament available: [www.machinablewax.com]. I'm not sure you'll be gaining anything by printing the ceramic directly.

Quote

I'm not sure you'll be gaining anything by printing the ceramic directly.

If you could do it reliably, you'd be replacing an immense amount of human labour or $500k+ of specialized automation equipment.

Edited 1 time(s). Last edit at 07/11/2016 03:17PM by n8bot.

Hmmm. Pouring the liquid ceramic over the wax mold (or dipping the mold in the ceramic) doesn't seem to take an immense amount of labor or even very much money. The most expensive equipment is a kiln and a vacuum chamber, hardly $500k.

... depends on how you'll do this - [tsf.de]#

Company video - [tsf.de]

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]