Tried a long print and lost power

[ChaosLord10 0]

Backstory made short, I started an 8 day print and suffered a power outage, then another, followed by two more.  I have an AnyCubic Chiron.  It is supposed to be able to resume a print after restart or power loss, but I think since there were multiple failures in a row, it lost the print. Left me with 90% of a Mandalorin helmet (dying inside).  Anyway, after being a bit gun shy for a few days, I opened the model in MeshLab to split and export the model to print the last 10 percent and glue the model.  That's just so much material to go to waste and I haven't bought a shredder and filament extruder yet.  Now to my problem... I was able to cut off the top 10% of the model in MeshLab and export back into .stl format.  When I slice the model, it adds a "lid" (my choice of word, not Cura's).  The model is just the top of the helmet.  bowl-shaped. I have scoured the internet and keep seeing something called "fix terrible settings", but can not find them anywhere in Cura 4.13.1.  Some of those posts are several years old.  Is there a way stop Cura from closing off a model that is supposed to be open?

 

 

Edited July 2, 2022 by ChaosLord10
I flipped the models to show no roof on the MeshLab model

[GregValiant 1,110]

That is a bad cut.  Those jagged edges look a lot like open seams to me.  That would confuse Cura and you will get wierdness in the slice.

 

Instead of altering the model, go into the Cura Preferences and turn off "Automatically drop models to build plate".  Then in the "Move" tool dialog set the Z to a negative number to sink the helmet into the Cura build plate by whatever 90% of your model height is so only the top 10% is exposed.  It should slice OK like that and you wouldn't have those jaggies to deal with.  The support should generate OK as well.

 

[ChaosLord10 0]

Thank you, I'll try that.  I've only been using Cura for a few months and am still learning a lot of the functions.  As far as MeshLabgoes, only a few days.  Still trying to make heads or tails of that lol. I'm planning to try to tackle it tonight after a Vase I've been working on is finished.  I'll most likely post the finished print and final product whenever I have the time to.  I was hoping to just be able to polish the whole thing after assembly, but with a seam like that, I may have to sand and paint it before I put in the visor. Thanks again.

 

Edit: Also, in my defense, the jagged edge was created by MeshLab. I just have no clue how to fix it yet. 😅

Edited July 2, 2022 by ChaosLord10

[GregValiant 1,110]

If you are using Windows, it has MS 3D Builder included.  I have found that it isn't real intuitive, but for simple things like cutting an STL it works pretty good.  Open the helmet, bring in a cube from the menu, size and move the cube till you like it, and with the cube selected, and the helmet NOT selected use the "subtract" tool.  You will get a nice clean edge.  Then do a Save As for the new model.

MS 3D Builder is also pretty good at repairing problems in models.

 

It looks like Mesh Lab simply erased a bunch of triangles without sealing the gaps.  You want a boolean operation there (Subtract, Union, or Intersection).

[ChaosLord10 0]

This is a lot of great information. And yes, it seems like MeshLab deleted any polygons attached to the line where I tried to cut instead of making a clean line. I shouldn’t have expected that it would clean up the edges. I was just going to take the time and sand it down after printing until I had a clean level edge to glue. That being said, I tried what you suggested and thus far it has worked like a charm. I didn’t know that you could sink a model below the build surface, it always snapped back up. I set it to .1 mm per layer and slowed the print speed to about 50 mm/s because I’m using silk PLA (It seems to like to run hot and slow.) then added tree supports (a little less waste) touching the build plate at an overhang angle of 70°.

[GregValiant 1,110]

Silky silver PLA is probably my favorite.  The layer adhesion sucks so I don't use it for functional parts but for things like that helmet it's perfect.

When you get done with that print try a silky silver print with the outer walls at 35mm/sec.  In my (never humble) opinion it's about as close as you can get to chrome.

[ChaosLord10 0]

I’ve been slowing it down by about 5mm/s every time I use it and it looks better every time. I worry about overhangs with it going so slow, but I’m sure the layer adhesion would be about perfect at that speed and temperature. Usually I do small test prints whenever I get a new material and start at the low end of the recommended temperature and adjust up or down by 5° each time. That and I like to push the speed to see what kind of bed and layer adhesion I get then slow it down until I’m happy with the smoothness of the walls. Then, because I’m a nerd and overly organized, I keep a journal and an excel spreadsheet of temps and speeds I’ve used. Short list currently, but it’s expanding.

[GregValiant 1,110]

I kept a journal when I started into this.  I did refer to it a couple of times in the beginning but I think the important part was simply keeping the journal because organizing it and looking at it kept me thinking about what I was doing.  

[ChaosLord10 0]

I know what you're going to say.  This shirt is bananas lol.  Anyway, I was able to sand down the edges to almost a perfect match and the finished product looks great.  Thank you for your help

[GregValiant 1,110]

Bananas!!!!  You want bananas!!!

 

"Just bit my shiny metal..."

You can just make out the "Double Cross" awarded to me by Tricky Dick Nixon's head when I saved the planet from the Scammers.

[ChaosLord10 0]

Ah yes, the Dirty Double Cross.  Just be sure to keep your fuel cells charged with plenty of wholesome nutritious alcohol lol.

You should print yourself the $300 Tricky Dick fun-bucks

Edited July 12, 2022 by ChaosLord10

[GregValiant 1,110]

I printed $3 bills with a picture of Bill Clinton.

 

BTW that was a very nice save.

My little printing app has a utility that will print from a "byte location" within a file.  I can start a print from anywhere within the gcode file.  I was hoping to make saving a print less tedious.  Ha!!