STL uploading problems

Hi everyone,

We found that uploading STL file in Preform was a bit challenging.
We use JewelCAD software to create 3D model and make a batch of those models then convert it to STL. We tried one single batch that occupied the whole print area (140x140mm). We have tried several file sizes (of a single batch): 4 GB+, 2 GB+, 1,1GB and below 1 GB.
So far, we succeed to upload the 1,1 GB file without repair, and file not more than 700MB with repair option, in to the Preform software.

Some questions:

  1. Do the XY resolution and Z thickness we export from JewelCAD software will affect the printing result of the Form 2 printer? If yes, what is the optimum resolution and thickness should i have?
  2. is it normal to have such big file size to be uploaded to the Preform software?

Sorry for my bad english by the way:stuck_out_tongue_closed_eyes:

Just an idea, i wish Preform supported .SLC format file one day.

Are your parts high detail? Most of my 3D files are much smaller than that, even when I subdivide them to get them smooth enough. Like less than 100MB

Yes, they are. What kind of object you usually do? We are doing small prongs on the jewellery. So it is kind of high detail. what resolution do you usually use?

I do miniature type stuff, there some high detail stuff like pipes that are around 300,000 polygons for them all together. Some big parts are around 200K to get them smooth enough.
1GB is a very large file–most likely your resolution is too high. I use 3ds Max, so when I print I check what the model looks like without smoothing which will show if it looks faceted or not, if so then I add some subdivisions to increase the smoothness. My guess is you have it set too high when you export to STL.

I see… I will post the batch i talked about, so you may get an idea about it.
I haven’t received my Form 2 from my local distributor. So i haven’t done any printing yet by myself. I try to export few files and prepare them to print test on the Form 2 as soon as it arrives.
Zachary, do you ever try to print a similar object with different file size? Did it do a significant or dramatical difference in term of smoothness?

I have tried to export the STL file with following resolution:
XY: 140microns (to match it with the Form 2’s laser spot size)
Z: 100microns
And the whole batch will be 1,1GB in file size.

Output the STL for a single object only, bring it in to PreForm, and then use the LAYOUT function to replicate it instead of creating an STL that has all the objects in it already.

I’ve found that exporting from blender as .obj rather than .stl has a better chance of having netfabb (Preform’s engine) import it with less hassle. If you can, try exporting to .obj filetype.

The software I use doesn’t have a setting for resolution, I just look at the mesh and see if it looks faceted and if it does then I smooth it more. Most likely your software is basically converting the model to that type of polygonal mesh like what I am doing, but it’s smoothing it too much which is making a high polygon count, I’m not sure what options you would need to adjust to get it to a more reasonable level.

I use Artcam (Same as Jewel Cad without a few options)
I have noticed on other projects that Artcams Export is pretty sloppy. It really wasn’t designed for exporting since it works on a Height-map (256 levels of Grey) vs a nurbs or mesh.
I always had to import the STL or OBJ file into rhino and run the mesh repair before using it as I would never get a truly “Closed” model.
There are some stand alone mesh checking programs out there but since I gave up on artcam except for my cnc routing I haven’t had a need for them.
I honestly would take a look a new program for design. I use Rhino and have been very happy with it. There is better programs out there but I have been using Rhino for so long that I don’t feel like learning a new one. I have heard good things about Blender and the price is right. “Free”
I have downloaded and installed Blender just haven’t had the time to work with it much so I can’t comment, the main reason is I was trying to use Z-Brush for some sculpting but the interface on Z-Brush was causing my head explode. (I am a Technical artist not very good at freeform modelling)

I use Blender for CAD, which pushes it’s envelope a bit as it was not designed to be a pure CAD tool. That said, once you get the hang of it, it’s really an amazingly beautiful program. It is incredibly stable (I use it on Debian sid with the e17 wm). I can’t remember the last time it did something weird like hung or crashed. It simply does not happen. The interface is also very slick and powerful. I have 3 monitors, and it easily works across all three in different windows with the same project loaded. Probably the best engineered program I have ever used, regardless of type - period.


@Randy_Cohen : Thank you for your advice. We will try it out. My consideration is the efficiency of spaces we use. so we need to arrange the object as close as possible.

@ChristopherBarr : I will try Blender then… Our worker have given it a try on Blender but i forgot how the outcome was.

@billiejean : i see, practically our workers have a big learning curve to migrate to the other CAD software. Hopefully can work this out. I will try to print my 700+ MB file and give you all an update. My Form 2 will be arriving in 2 weeks. Can’t wait to run a test in full print area.

@Zachary_Brackin : i see, so let me try some adjustment and see how it goes. I will try the 700+ MB file first.

Please show a screen shot… I would love to see what a 700meg STL looks like… That is just insane. :wink:

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Yeah, 700MB is still ridiculously large. All of my STL files are less than 20MB

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I very rarely use stl files. Obj files are far more user friendly.

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That’s interesting. In what way?

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This is the 700+ MB file i was talking about. Please give comments

It’s a format that can easily be used in a variety of software programs if editing is required (which I often do). They tend to be resonable in size too. Stl files tend to be less friendly (3ds max hates them).

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@JasonSpiller : i see, but i have no option other than STL or SLC on my JewelCAD 5.1

That’s a downer. Meshmixer is a free program that let’s you import stl and save it in obj - for some reason it creates quite large obj files so I always resave in another program (blender for example).