Anycubic Photon

[Chris333]

Shut off/re-set 5 more times, once it made it to the 3rd layer before shutting off.  I shut it off, going to bed...

[DKS]

I shut it off, going to bed...

Wow... you actually sleep?

[tom mann]

I shut it off, going to bed...

Wow... you actually sleep?

I assumed that "going to bed" is an Anycubic technical term

[Lemosteam]

Netfabb says 0 holes, but 4 shells. Whatever a shell is.

I'll try Meshmixer when I get home.

@Chris333 , a shell is a 3D body.  Since you added four bodies together into one file, the bodies may be face to face or line to line in a section or even overlapping (see example below) but not JOINED into one body, so the system thinks there are still four separate parts.

Here are cad examples of the same design in section, two shells (bodies), and a single body after a boolean join operation in cad.  The two upper are in CAD and the two lower are .stp files show sectioned in my viewer.  The left pair would be interpreted as two shells and the right as one shell. take note of the white tessellation lines (read on) on the surfaces in each example:



If your CAD tool has boolean operations, you will need to create a body the runs through the joints and makes all if the bodies into a single body (as if you modeled it as a single body).  Think of it as the glue in the joints.

Translations (.stl, .igs, .stp, etc.) of CAD models are not perfect, particularly .stl files as .stl files use triangles to simulate the perfect solid.  Even on a square flat plane, .stl conversion could turn that into a minimum of two triangles or many.  This is known as Tessellation.  Also these types of translations ar known a "light" data because the translations use only the surfaces, not the solid ("heavy" CAD) to make it easier to load into a viewing tool.

This imperfection can lead to infinitesimal gaps between surfaces that LOOK like they intersect but in fact do not.

As a good practice, .stl files should not be modified, rather always work in the master CAD file from your CAD software and export a new .stl.  "File>Save As" is cheap if you don't want to disturb your original CAD file, to make a new CAD file for different printing needs.

Here are four examples of popular conversions of the same part in my viewer and the first image is in my CAD software.  I have turned on "edges" (black) and Tessellation lines (white) so you can see them, surfaces are grey.  Note the different interpretations by each conversion.  And to top it off, if you made a slight topographical change in any of the features, the tessellation might be completely different the next time.
 

[Chris333]

So where do all the extra triangles come from? I can understand if the parts aren't closed or are overlapping, but the result looks like someone scribbled all over my drawing. Things that do not show up on any screen are somehow still there.

These are just 3 slices from my drawing:



All 3 of those should look just about the same.

[Lemosteam]

Wll then you throw in yet another conversion tool and it does not know what to do with the .stl data.  It's a software guess no mater how you look at it. 

The point is, always start with a clean 3D model and all of the downstream conversions should be consistent.

[haasmarc]

Here is a pic of the trucks supports.

Thanks Chris!

[rodsup9000]

 And 13 hours later, this is what I got. I think I over did the support, but I didn't want a failure. It looks like the supports used almost as much resin as the print itself. The keystone at the top of the arch came out beautiful. I think he'll let me do his printing now.

 Give you a idea the size. Build plate is about 3" X 5 1/4".

 





 All the supports I used













Supports removed









And the keystone.

[Chris333]

The arch looks great!

Before I went to bed I tried one more time... Didn't want to clean the plate again so I just raised it up and pulled out the vat. I slid a piece of transparency film under the plate and re-zeroed it. Put the vat back and hit play. No problems at all and now I have grey trucks.

So it was still level and I think it was losing it's zero.

[chessie system fan]

I like it.  What color did you use for the arch?

[peteski]

I like it.  What color did you use for the arch?

Looks like "sandstone". 
Sorry, couldn't help myself.

EDIT:  Uh, I should have also mentioned that yes, the portal looks great!  And the keystone looks like a work of art (not a typical keystone)!

[rodsup9000]

I like it.  What color did you use for the arch?

Aaron. It's Anycubic White.

The arch looks great!

 Thanks Chris.

[Chris333]

I printed a set of trucks in grey and they came out great. Load up the USB with my revised ore car and the Machine stopped/reset at the first burn. Didn't even try it twice. Pulled out the vat and re-zeroed. Pressed play and it is printing now with no problems. Someone told me the power supply is getting a surge when the UV lights kick on.

[Chris333]

So I bought 500ml of gray resin on ebay for $38. Went to buy another bottle from the same seller and it is now $29.

[Mark W]

It's the same on amazon, which is awesome news!  I'm starting to think this is not a limited time sale, but rather a full time price reduction!!