Build Your Own SLA/SLS

Here's my DLP resin printer. The mechanics are pretty much finished, just waiting on someone to produce a good, low shrinkage resin. It's frame is 8020 extrusion, very simple, minimal layout. Using a $150 (ebay) Mitsubishi projector at 1024x768 resolution. My build area is 4.5" x 6" with about 6" z height. It was basically built as a test bed. Once I knew the concept was viable, I would build it into a more enclosed structure. I don't have a blog for the build, just a few pics.

I'll post more on my tilt and vat in the other forums of those subjects.

Hey Jon,
Nice to see you're over here too.
Looking good.

John

Incredible results! Can I get that Iron Man model from you?

Hey John! Yeah, I just discovered this forum. Hope to share some good ideas here.

Steve, here's the War Machine model. It's a Yousendit link. Let me know if it doesn't work. I downloaded the model from GrabCAD so you can get it there is all else fails.



Jon

Very nice, the Z stage looks good, wish I had that much space in my workshop. how did you do the supports for the iron man? they look angled.

Hey John, thanks. I created the supports using the B9 creator software. It's free and has good support tools. It will allow you to place supports where you want and also angle them at the base and change their thickness, angle at the top where it touches the part, How much it penetrates the part, how large the base of the support is, etc. lots of support parameters to play with.

I start with B9 Creator software, I create the supports, then export the stl (with supports), then slice in Viscam, Over sample my slice images to 600 dpi. Then batch process the slices in Photoshop, bringing them back down to 1024x768 resolution. It's a drawn out process but being able to up sample the layers allows for smoother prints, virtually doubling the resolution of the print.

I've done quite a bit of testing to show that antialiased layer bitmaps work better than native resolution layer bitmaps.

I had Viscam at work for a while, why do you use it, (expensive), why not add a feature request to do
the image processing to creationworkshop, and support stuff, we always seem to need tool chains in cam,
image processing, etc, to get the best result, each step adds potential errors, Pacmanfan, (steve) is willing
to entertain any suggestions.

Here's a stupid thought, would svg give smoother images, as its vector based, must confess I am talking here about
something I know little about, (suppose it all comes down to pixels in the end).

slic3r outputs svg's but they look like to have the same quality as with creation workshop

Yes, I think maybe the svg thing was a dumb idea,
watsonstudios, just so this idiot can understand, are you going from 90dpi to 600dpi, what filter, bilinear ?., sounds like
it gives smoother edges, therefore smoother prints.
But the resolution of the dlp would be the overriding factor perhaps, just trying to get my head aroud this.

I'm creating my slice images at 600dpi, which makes them 3600 x 2700. Then, I take those and sample them back down to 1024 x 768 using the batch feature in Photoshop. Here is a chart I made that shows the difference in quality when using oversampled slice images. It's just about doubling the resolution of the part and smoothing out the print. This gives very similar results to the "pixel shifting" that Envisiontec uses. Pixel shifting involves moving the image the amount of 1/2 the pixel size in all 4 directions, (up, down, left, right) this effectively anti aliases the image similar to the oversampling method. You will see in the attached image the difference it makes.


I did message Steve about maybe putting this feature into CW. You should have the option to output the slices at any resolution you want.