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kyuzo
10-04-2017, 08:57 AM
Bit of an odd one, and I've tried exporting with different settings, but I haven't seemed to get it working right yet.

I often export models for production, and so I export from lightwave using the built in .stl exporter. Works fine. Looks fine when I load the stl back into lightwave.

However, when the mould producer imports the file, the model is flipped in the X direction. I can check this by loading up the file into an online .stl viewer, and it also shows up flipped. Every time. It's no big deal, as I just remember to flip my model before export, but it'd be nice not to have to.

Been meaning to mention this for a while now... Anyone else had similar?

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138179

10-05-2017, 08:40 AM
"Mould producer" might be the culprit.
This isn't a function of the software, is it? What program is ingesting and flipping the model?
In reading this the thought occurs: is this an app that could make a stamp, a negative from a positive kind of tool?
Perhaps in the loading process there is a way to turn off the, "Flip inside out", function in that tool.

p.s., I have seen this before but don't recall what the issue was.

ConjureBunny
10-05-2017, 09:30 AM
Hi Kyuzo,

Try my free ExportSTL script. I wrote this back in 2013 to correct a few really minor math problems in an earlier one I found online, and to fix Mac path compatibility.

One important, vital note: turn off symmetry. For some reason this makes your print wonky.

I use this script at least once a day. I might have a 3d printing 'problem', now that I think about it. Wait, the only problem I have is running out of filament. But anyway, it works great. Straight out of LightWave. And if you have any problems with it, let me know, and I can fix it :)

http://www.liberty3d.com/2013/03/freebie-export-stl/

-Chilton

kyuzo
10-05-2017, 10:00 AM
"Mould producer" might be the culprit.

That was my first reaction too. I guessed that there was some setting in their software that was screwing up the axes. Then I dropped one of my models into a free online .stl viewer, and it was flipped there too. So I stopped blaming the mould producer, and just resigned myself to flipping all my models!

Thanks for that script Chilton, I'll give it a test and see how it works.

Cheers,

Derek

kyuzo
10-06-2017, 03:22 AM
Hi Chilton,

I've had a test with your script, and have made a couple of observations... :)

The models I am creating are usually 'slab' style designs, with the width along the X, height along the Z, and the thickness up the Y axes. They are usually centred on the origin, but resting on the Y+. (Using the 'Rest On Ground' button)

When I use your script, the .stl that is created views correctly in my stl viewer. So that's good.

If I open the .stl in Lightwave to check, it is flipped left-right, and the whole model has been moved into the X+,Y+ and Z+ area, resting on the 0,0,0 planes of each axis.


So, couple of questions to satisfy my curiosity:
Where do you position your models in lightwave when you model them for .stl export?
And do you work to the standard LW axes, with Y as 'up', and Z+ as forward?
Do you ever bother opening your .stl files up again in Lightwave?
Am I just wasting my time expecting the orientation of the .stl to match in both LW and other software? After all, if they have different coordinate systems, then it seems like it'll never happen...

I'm going to send a file exported with your script to the mould maker and see if that works for him. If so, then I'd say your script does the job perfectly well.

Cheers,

Derek

ConjureBunny
10-07-2017, 02:35 PM
Hi Chilton,

I've had a test with your script, and have made a couple of observations... :)

The models I am creating are usually 'slab' style designs, with the width along the X, height along the Z, and the thickness up the Y axes. They are usually centred on the origin, but resting on the Y+. (Using the 'Rest On Ground' button)

When I use your script, the .stl that is created views correctly in my stl viewer. So that's good.

If I open the .stl in Lightwave to check, it is flipped left-right, and the whole model has been moved into the X+,Y+ and Z+ area, resting on the 0,0,0 planes of each axis.

So, couple of questions to satisfy my curiosity:
Where do you position your models in lightwave when you model them for .stl export?


Same as you, I use the Rest On Ground thingie in LW. F3, I think. I forget what it's called, but I think it's Rest On Ground.




And do you work to the standard LW axes, with Y as 'up', and Z+ as forward?


Generally, yes, but only because I'm lazy and I don't think about it often. Until this very moment it didn't occur to me that there might be a different way to do that. Huh.



Do you ever bother opening your .stl files up again in Lightwave?


I have not done that before. But IIRC there was an ImportSTL that had the same math errors, and I didn't bother fixing it because I don't often need to import STLs.




Am I just wasting my time expecting the orientation of the .stl to match in both LW and other software? After all, if they have different coordinate systems, then it seems like it'll never happen...


Yeah, probably a waste of time.




I'm going to send a file exported with your script to the mould maker and see if that works for him. If so, then I'd say your script does the job perfectly well.



Awesome! Please let me know how that goes!

-Chilton