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Monday, October 28, 2013

Creation Workshop Beta 12 is out!

It's been a long time coming, but I just released Beta 12 of Creation Workshop. There are far too many new features to start listing off, but I'm going to try:
  • Improved UV DLP Slicer
  • Export to zip file or sub-directory
  • Support generation (automatic and manual)
  • Ability to reload previously sliced models
  • New machine configuration screen
  • New slicing profiles configuration screen
  • Support for FDM printers using Slic3r to slice
  • Serial projector control
    • ability to add new projector commands
  • 30% faster rendering
  • New User manual 
  • Improved move/scale/rotate controls
    • ability to drag around objects with mouse and shift key
  • Everything else I forgot...

You can get it from the usual spot here: 


I'd love to hear about any constructive feedback / feature requests / bugs. Help me make this a great piece of software, and don't forget to donate :-) 
-Steve

Saturday, October 19, 2013

More Pix

I took a few more pix and video of my machine in action. I was able to get a few more prints off the machine when it broke again.

My machine fell victim to UV resin-dissolving ABS-eater again. 
The 'before' pic

Some of the aftermath

I rebuilt the Z-Axis Build-Arm.
I used some 5mm aluminum plating I had laying around to re-build the z-axis build arm. I added some 5mm bolts with double nuts on the bottom to help adjust the build plate to parallel with the vat. Wingnuts tighten down the top.


Gender-bending required.
 I'm adding some basic serial control of the projector through an open serial port. I purchased a small F-F gender bender and started some programming. Instead of simply hard-coding some commands to control my projector, I took a more universal approach that allows the user to create new commands, give it a name, and assign a hex string to send to the projector.


The relocated power panel.
 I moved the power panel from the back of the machine to the side panel. I plan on adding another small panel for connection to the USB hub connected to the usb/serial connector to the serial port of the projector. I also have the Arduino connected to another port on the USB hub.

Goldberg Sphere. 50 micron accuracy Z, 100 micron X/Y, Dimensions are 15x15x15mm



I had a few more good prints out of my machine before it died again. I am very proud of the resolution attainable.



The rear bearing holder piece broke. I was sloppy with my dripping resin.
I really need to take more care and caution in dealing with chemicals. I've damaged several ABS printed parts to UV Resin. I printed another rear bracket. I just may soak it in UV resin and cure it to create a meta-material part.

The weird part about these parts dissolving is that they simply crumble into pieces. I've treated many ABS parts with acetone vapor, and parts simply 'Melt' a bit like cheese or butter, to smooth and harden parts. This UV Resin must be destroying the long CH bonds from the polymer molecules in the ABS. I think if I want to try a chemical UV bath and curing session for an ABS part, I should do it quickly before the ABS has a chance to break down.

 I'm already ordering parts for the next version of the printer. I'm going to name this version the "Mark I". The 'Mark II' version will have a much smaller projector that I recently ordered http://www.aaxatech.com/products/p2jr_pico_projector.html . My plan is to make a z-axis with a single linear rail and simplified build plate/vat design.

I also ordered a peristaltic pump. My plan is to have a simple forward/reverse switch connected to the pump to control the flow of resin in/out of the vat. 

We'll see what the next iteration of the machine will hold. For now, I'm going to fix my machine, keep printing, and improve my "Creation Workshop".

Wednesday, October 16, 2013

A Win, a Failure, and another Win?

Warning: This is going to be a pic-heavy post.

The success

So, as many of you know, I've been working hard on my software -"Creation Workshop", preparing for the next Beta 12 release. I've finally found some time to re-build my UV DLP machine to produce some proper prints. Last night, I made a few successful test prints on my newly re-designed machine.

Shown here is the newly- redesigned machine.
My previous setup had issues with the stability of the Z-Axis. It had too much wobble and play in the z-axis, and this was causing issues with separating the model from the vat, as well as creating z-artifacts. As you can see, the Z-axis has been completely rebuilt with 1010 T-Slot aluminum extrusions. 
I folded the geometry of the machine. The projector is now laying horizontally, and I use a FSM (Front Surface Mirror) to project the image onto the surface of the vat. The new Z-Axis is rock solid. Also featured on this machine is a tilt mechanism which helps separate the model from the PDMS coated vat every layer.

A top-down view of the Vat tilting mechanism.

I took the time to install a limit switch for the Z-Axis, so I know when the build plate is exactly touching the bottom of the vat. I used the X-Axis to control the tilting mechanism, and placed a limit switch for the X-axis to trigger when the vat was perfectly level.

Now, I can use homing for the X&Z axis's to move the machine into the initial position.

After a bit of fiddling, a code change, and a ton of calibration and dry runs, I decided it was time to make a test print. I chose the 'Tardis' model.

My first 'Successful' print.

I had a mechanical failure at the last few layers, but overall, it was a good print. I'm still going to need to fine-tune my layer times and Z/X axis movements.


The Failure

I'm always a believer that a failure can teach far more than a success. My machine definitely failed in an un-expected way. I (re)built  most of my Z-Axis using 1010 T-Slot extrusions, however; there were a few choice FDM-printed parts in the build.

Some history
One thing I noticed a few months ago was that the 3d UV Resin I was using was EXTREMELY corrosive to ABS plastic. I had spilled a few drops of it on the tilt mechanism, and the plastic all but dissolved right before my eyes.

I had a similar failure last night. Here's a pic of the destruction:
The UV Resin dissolved the ABS

This L-Bracket as well as the printed green 3x2 plate were dissolved by the UV Resin. Catastrophic failure occurred approximately 1 hour into the print.

 
The bottom half that attaches to the build plate.

The issue is that the UV resin came over the side of the top of the build plate in the vat. It then traveled by capillary action up the ABS fibers of the green plate and the grey L-brackets. Both FDM ABS prints were dissolved and failed.

The Win?

  My initial guess is that something in the un-exposed UV resin acts as a solvent for ABS plastic. Interestingly enough, my last iteration of my z-axis had this same problem that I was able to avoid. My last Z-Axis also used a 3d-printed ABS interface plate. How did it avoid destruction?
A plate used to connect the aluminum build plate to the Z-Axis on my last machine
As I recall, last time I encountered this, I saw the UV resin was soaking into my printed plate, and I quickly used my UV Laser to cure the resin embedded in the ABS plastic. This worked out well and made the interface plate solid as a rock.

Composite materials
After the failure with the brackets and the plate last night, I re-examined the saturated - cured interface plate from my previous Z-Axis. The resin had completely become embedded and hardened within the material. After a few un-scientific 'hardness' tests with a hammer, I believe that this composite material is much harder and tougher than either ABS or the UV would be on it's own.
I may have to do some more testing with saturating FDM printed ABS plastic with UV Resin and curing the material to test durability of parts in the future.

Next Steps

My machine should be simple enough to fix. I'm going to replace the printed L-brackets with aluminum brackets. I'll probably take the time to add in a screw-adjustment for leveling and quick removal of the build plate.

I'm very happy with the results of my first printings, I think now I have a working machine to test with, adding new functionality to my 'Creation Workshop' shouldn't be too difficult.
-PacManFan