[Sanghera]

What software do you use to create the toolpath? Where do you input your z axis step-over? Does anybody know of any commercial software that converts to g-code, or maybe shareware/freeware?
Thanks.

[jams002]

wow this is great topic interesting to read,Rapid Prototyping

[Kipper]

There really isn't a way (that I can think of) to get around making hollow, sealed, internal cavities in an object and not make the support material a permanent part of the object. I know that this is a limitation of a couple of commercially available "powder bin" based machines.

What would be ideal is a material that would breakdown over a short period of time but stay rigid enough during the construction process. Of course, I'm not a chemist so I think I'll just have to live with having either no ability for internal hollows, or have the support be a permanent part of the object. Having said that, because this is just a prototype machine, i'm pretty ok with either of those situations. But I'm open to any ideas!

At the moment the leading canidate for a support material is wax that can be dissolved or melted away in water.

A Zcorp will "print" (it uses a HP print head and powder) two or more gears...in mesh on shafts with ball races that turn....Quite a clever piece of kit....Although expensive on consumables! I have a pattern for a motorcycle triple clamp made with one...I wonder if a laser would "fuse" controllably (

[daedalus]

You can do SLA type rapid prototyping with conventional DLP projectors to set the resin. Here is a youtube video of someones design:

[ame=http://www.youtube.com/watch?v=snOErpOP5Xk]3D Printer - High Resolution - Homemade - DIY - YouTube[/ame]

The actual process is public domain, having been released by Center for Nanoscale CEMMS as part of their outreach program, so ignore the video authors 'patented' ramblings.

I have uploaded a guide to the process, which includes what chemicals to use. This is aimed at lab demos for highschool kids, but works equally well on a larger scale with an automated build tray and 'proper' software.

[doorknob]

I have uploaded a guide to the process, which includes what chemicals to use. This is aimed at lab demos for highschool kids, but works equally well on a larger scale with an automated build tray and 'proper' software.

Thanks for posting the link to the experiment guide. I had seen this demonstration video some time ago, but never found any more details about the process.

Are you aware of any forums where the DIY use of this process is being discussed?

[Phife]

This is very cool! I like the idea of using a projector to project a layer onto a Light sensitive resin.

I already have an old DLP and a CNC, I think the hard parts are making/sourcing the resin and the software to sync the projector and Z stage.

Very Interesting, I hope this takes off!

[daedalus]

The only places I know of where this technique is discussed is the blog listed on the youtube video I posted, but it appears to be very simple. I found a source for the chemicals in small quantities, but their website is set up for business customers mainly.


1,6-Hexanediol diacrylate:
http://www.sigmaaldrich.com/catalog/...AND_KEY&F=SPEC

phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide:
http://www.sigmaaldrich.com/catalog/...AND_KEY&F=SPEC

sudan I dye 97%:
Sudan I Dye content 97*% | Sigma-Aldrich.com

Note that sudan dye is used to block uv penetration into the fluid, so it may be possible to use a substitute material for this. Sudan 1 is a food dye that was banned for being carcinogenic, so you can only get it from chemical suppliers now.

All of the above will set you back around £70, and make up a batch of 100ml of fluid (most of the cost is for the additives). The major constituent (1,6-Hexanediol diacrylate) can be sourced much cheaper in larger quantities, these lab suppliers add a significant markup.

When my next pay packet turns up im planning on making up a batch to experiment with.

As for the build tray, im planning on using a salvaged thk kr22 track with a stepper to automate the build tray movement (controlled from a netduino at the moment). Software wise powerpoint works fine for testing, but will have to put together something more useful eventually. Im a software dev by trade so shouldn't be too much of a problem.

[awerby]

Thanks for posting the link to the experiment guide. I had seen this demonstration video some time ago, but never found any more details about the process.

Are you aware of any forums where the DIY use of this process is being discussed?

There's a Yahoo group which has been actively experimenting with a similar technique; go to diy_3d_printing_and_fabrication to get involved.

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

[doorknob]

There's a Yahoo group which has been actively experimenting with a similar technique; go to diy_3d_printing_and_fabrication to get involved.

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

Thanks for that pointer.

For others who may be interested, here is a link to that group:

diy_3d_printing_and_fabrication : DIY 3D Printing and Fabrication

I haven't read enough of the messages yet to determine whether or not there is a specific "project name" that people use to refer to this specific approach to 3D fabrication...

[daedalus]

awerby: thanks for the link, I didn't know about them. From looking through the mailing list these two pop out as almost exactly what I was planning to build.

3 D L P rint
ChemShapes

chemshapes are discussing a more rapid approach to curing the resin, but don't give much detail as of yet. Im guessing they are using pure resin without a UV absorbing filler (which should be possible with computer controlled exposure). They also have links to cheaper off the shelf resins for use with the project.