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AlexV
04-11-2015, 07:01 AM
(Using Lightwave 11.5)

Hello,

I've always used Lightwave for modelling when I was younger and recently I have purchased a 3D printer. Though I enjoy working with Lightwave a lot as I know how everything works and I can work so much faster as I know all the shortcuts for the different tools, Lightwave does seem to have an issue when exporting to STL. Basically it exports the STL fine, and nothing out of the ordinary is noticable. However, when using the 3D program to print the actual model, you can scroll through the seperate layers and that's were the problems arise.

When scrolling through the layers, invisible planes appear in places where you don't want them too. Unfortunately the printer prints these invisible planes as well, creating a huge mess. It seems to happen when exporting to STL (or .obj) with both modified (imported) stl's as well as genuine .lwo files created by myself.

I've only had this issue when exporting/saving models as STL's in Lightwave and haven't had this issue with other 3D programs (Solidworks for instance). Unfortunately I still need to learn to work properly with programs such as Solidworks, but I'd prefer to use Lightwave in most cases.

I know the stl exporter isn't an official Newtek plugin (Chromecow), but perhaps one of you has had similar issues and has been able to fix it.

Here's an example of what I mean:

This is what the model looks like in Lightwave. No visible problems:
127822

Here it is showing in the printer-software. Again no visible issues:
127823

However, if you scroll through each layer, a lot of these layers look like this:
127824

127825

Unfortunately, these layers do get printed and create a big mess on the inside of the model.

I'm looking forward to your professional insights and possible solutions.

Thanks

Alex

JoePoe
04-11-2015, 07:33 AM
I can only speak to the LW side of things.... but let's start simple anyway right? :)

What's in the five other layers in the Lightwave object file?
(or does the export only use the visible layer?)

AlexV
04-11-2015, 07:51 AM
Hehe, nicely spotted. These are all separate parts which together will form the full print. However, these layer do not interfere with exporting. Like you already mention, it only exports the visible layer. To ensure that wasn't the problem, I exported it in a "new object" as well, but unfortunately that didn't change anything.

Thanks for the reply though!

daforum
04-11-2015, 08:49 AM
Can you export each separate layer as a separate .stl?
And doesn't an .stl export need everything in 1 layer ( even though it's made up of different layers ie: not connected parts )

Also does tripling the polygons before exporting help?

AlexV
04-11-2015, 12:07 PM
I'm not quite sure what you mean, daforum. Lightwave's stl export is very basic as you probably know. The 3d printing software is used just for positioning and uploading to the printer. The only reason you can scroll through each layer is to ensure that every printed layer is supported. That's it.

Exporting single layers is not an option. Furthermore, I don't know what the requirements are for an stl to work. The thing I don't understand is that these "invisible" layers are obviously there (in the code) but I'm unable to select them and therefore I cannot delete them.

Perhaps I'm interpreting your answer the wrong way. If that is the case, please explain a little bit more of what you mean.

Thanks

spherical
04-11-2015, 11:32 PM
I'd need to actually examine the file in question to be sure what is going on. Providing one, especially in an instance as complex as this, right in the first post would be most helpful in efficiently arriving at a cogent solution.

As a rule, I don't use the LightWave STL exporter. Instead, I employ a dedicated file format translator to write a file that I know will be rock solid. I model a LWO, then triple it choosing one of the Triple options (depending upon the geometry, Triple, Fast Triple Fan and Fast Triple Traverse will produce different tri configurations) in order to get tris that are less severely elongated. Then, the tripled file is saved as a separate object. It has ZERO other layers, as that will totally screw up a slicer. That file is then run through Deep Exploration to convert and scale it to an STL.

Having extra layers in any file going to a 3D printer will confuse the slicer (if it is smart enough), as it thinks that it either has sub-meshes or is Borked. I'm betting that if I ran your STL through KISSlicer, it would identify the cruft right out of the gate and throw an error. Competent slicers need clean geometry in order to understand the structure and determine the outside and the inside of the part and then break it down into thin layers, so that those layers can be re-assembled by the sequential printing process.

Yes, there are a lot of really dumb slicers out there that just aren't sophisticated enough to even see that there is something wrong with the supplied model. They'll happily slice it and most users think that this is a Good Thing. It isn't. Garbage in. Garbage out. Good modeling practice and good workflow solves a lot of issues.

Greenlaw
04-12-2015, 12:39 AM
Hi fellow Form 1 (http://formlabs.com/) user! :)

We have the same printer you have but we haven't had that problem with Lightwave files. Here's an example from a while back: Our First 3D Print: Sparklepus! (http://littlegreendog.blogspot.com/2013/07/our-first-3d-print-sparklepus.html).

And here's one my daughter created about a year ago: Sienna's First 3D Print (http://forum.formlabs.com/t/siennas-first-3d-print/437)

Re: "Exporting single layers is not an option." I'm not sure I understand. Why not?

I've only ever exported using the native Lightwave .stl exporter though, not the third party one from Chrome Cow that you mentioned. That said, I don't think the exporter is the problem. I agree with spherical that extra layers in a file is just asking for trouble. I don't know about the Chrome Cow exporter but the native one will automatically triple the mesh and check for potential problems with a file. In some cases, it will even fix things for you but naturally it's better to just get it right yourself and not rely on the exporter.

The only Form 1 specific setting you need to adjust in the native Lightwave exporter is to change the scale setting to mm. All other settings at default seem to work fine. I was told by Jen of LW3DG that the .stl format doesn't contain any scale data so the Preform software must be reading the arbitrary units as mm. Anyway, when I choose mm for the Lightwave .stl exporter, the scale seems to be correct when printed on the Form 1.

Just wondering, are you using the Form 1 or Form 1+? We recently upgraded our Form 1 to the new Form 1+. It's set up in our studio but I haven't had a chance to test it with Lightwave yet, let alone Lightwave 2015. Will try to do that later this week.

I noticed that you're using Lightwave 11.5; why not download 11.6.3 which has the native exporter?

Good luck and keep us informed on your progress. I'll let you know how it goes on this end with Lightwave 2015 and the Form 1+.

G.

spherical
04-12-2015, 03:23 AM
Re: "Exporting single layers is not an option." I'm not sure I understand. Why not?

It just isn't. If you export an object, it expects that there is only one layer. Other layers, whether they are active or not, WILL get included in the exported STL and you're toast. This bit me once. That was enough.


I was told by Jen of LW3DG that the .stl format doesn't contain any scale data so the Preform software must be reading the arbitrary units as mm.

Well then, I guess the geometry transform Scale factor in Deep Exploration has no use whatsoever and I can just disregard it. Not! If I don't set that factor at the correct value, then the resulting STL is WAY OFF!

AlexV
04-12-2015, 04:01 AM
I'd need to actually examine the file in question to be sure what is going on. Providing one, especially in an instance as complex as this, right in the first post would be most helpful in efficiently arriving at a cogent solution.

I agree! Here are two separate files. One is the original STL (saved as .lwo) which I downloaded from Thingeverse (I believe). It's a solid mesh of a rain drop. The other file is what I want to achieve. It's the same rain drop however I hollowed it using the boolean function and cut it into two separate pieces (again using boolean) because I need to open up the inside.

(there seems to be some problem uploading them via the attachement, so here's a dropbox link):
https://www.dropbox.com/sh/rp79dfnegu5s2hr/AAAs1lOBXJwNmN-_Zw6iEKgna?dl=0





Hi fellow Form 1 (http://formlabs.com/) user! :)

First of all, nice prints! I like what you did with your daughters drawing :).

I've only ever exported using the native Lightwave .stl exporter though, not the third party one from Chrome Cow that you mentioned. That said, I don't think the exporter is the problem. I agree with spherical that extra layers in a file is just asking for trouble. I don't know about the Chrome Cow exporter but the native one will automatically triple the mesh and check for potential problems with a file. In some cases, it will even fix things for you but naturally it's better to just get it right yourself and not rely on the exporter.

I realise we've had a similar conversation on the Formlabs forum. Me using Chromecow and you using the native exporter. Based on your advice (twice now), I've updated tot 11.6.3 and the exporter is definitely easier to use than the Chromcow one. Saves me scrolling through endless lists of utilities. However, the chromecow exporter seemed to do the same job. I did notice a slight diference. The native exporter ensures that the model stays hollow when choosing the "cap holes" option. The Chromecow plugin just makes it a solid (after repairing certain issues). However, If I deselect cap holes in the native exporter, I have the same issues as I had before. The invisible planes.

Conclusion based on this information. It is not the exporter that creates the problem. It's definitely the model... Perhaps you'll become a little wiser when looking at the files.


Just wondering, are you using the Form 1 or Form 1+? We recently upgraded our Form 1 to the new Form 1+

I'm using the Form1+.


The only Form 1 specific setting you need to adjust in the native Lightwave exporter is to change the scale setting to mm

Please tell me how. I've changed the Unit-settings to metric->mm but then it has to scale the model up by 1000x. So I just model things in meters (1mtr = 1mm in Prefrom) to get it to work properly. I hear there is an easier way to do this :P...

Thanks for all your contributions so far, guys!

Alex

Greenlaw
04-12-2015, 01:19 PM
It just isn't. If you export an object, it expects that there is only one layer. Other layers, whether they are active or not, WILL get included in the exported STL and you're toast. This bit me once. That was enough.
That's what I meant. Why not export each layer as it's own single file. It sounded like this wasn't an option for some reason. I was just curious why.


Well then, I guess the geometry transform Scale factor in Deep Exploration has no use whatsoever and I can just disregard it. Not! If I don't set that factor at the correct value, then the resulting STL is WAY OFF!
I was only referring to using Lightwave objects in Preform, which is what the OP is using. The scale factor between Lightwave, using the native exporter to Preform only requires changing the setting to mm because the scale is already determined by Modeler as far as these two programs are concerned. FWIW, even the docs for PreForm states that actual scale information is not contained in the .stl format. Also, Jen had referred me to this page for further reading: http://www.ennex.com/~fabbers/StL.asp.

Admittedly, I'm not an expert in 3D printing. Just passing on what limited experience I have with the Form 1 and sharing what I had been told by Form Labs and LW3DG.

G.

Greenlaw
04-12-2015, 01:34 PM
I realise we've had a similar conversation on the Formlabs forum. Me using Chromecow and you using the native exporter. Based on your advice (twice now...
Oops, sorry...that must have been a while ago. My memory doesn't last very long these days. Anyway, hi again. :p

Conclusion based on this information. It is not the exporter that creates the problem. It's definitely the model... Perhaps you'll become a little wiser when looking at the files.
Will do.


I'm using the Form1+.
Great! This will make it easier to troubleshoot since we're using the same gear and software.

Please tell me how. I've changed the Unit-settings to metric->mm but then it has to scale the model up by 1000x. So I just model things t in meters (1mtr = 1mm in Prefrom) to get it to work properly. I hear there is an easier way to do this :P...
Hmm. Maybe they changed something in the software recently. I haven't used recent builds of Preform and I'm just getting around to using the Form 1+. Will let you know how it works out this week.

Greenlaw
04-12-2015, 01:42 PM
Please tell me how. I've changed the Unit-settings to metric->mm but then it has to scale the model up by 1000x. So I just model things t in meters (1mtr = 1mm in Prefrom) to get it to work properly. I hear there is an easier way to do this :P...

Sorry, I misread this when I wrote the above. Actually, this sounds about right for me because I always model in meters in Lightwave, and setting the exporter to mm does a proper conversion to Preform. At least, that's all it's taken for my prints on the Form 1 so far.

I'll let you know if this is still true for me with the latest Preform and the Form 1+. I'll try out your object too.

G.

Greenlaw
04-12-2015, 02:01 PM
I did a quick export/import test, going from LW directly to PreForm, and PreForm reported an 'Integrity Issue'. I've never seen that error before so I guess there's something off about the mesh. At a glance, I don't know what that could be though.

Will take another look at it later today if I can manage the time.

I did notice that your model is 52 meters tall, which is obviously too big to fit on the Form 1's build platform. You should scale it down to fit the printable size first before exporting it. The I/O will go more smoothly/predictably this way since you will be working 1 to 1. This doesn't solve the 'integrity issue'. Will look into that later.

G.

Greenlaw
04-12-2015, 02:11 PM
Interesting. I broke it into to separate objects and I only get the error (the unwanted cap geometry) with the 'top' portion of the drop. The 'bottom' portion is valid in PreForm. That narrows the problem a little.

Greenlaw
04-12-2015, 02:19 PM
Okay, I see the problem. There's a narrow gap that circles the inside of the drop. The volume needs to be completely sealed to be valid for printing. You might be able to fix this using the Bridge tool? Just a thought. I'll see if that works.

G.

Greenlaw
04-12-2015, 02:39 PM
Yeah, fixing the gap with Bridge was all it took. Here's the object in PreForm after exporting directly from Modeler. I used the native .stl exporter using the mm setting. This outputs the object at the scale from Modeler after I scaled it to 0.1% so that it could fit in the Form 1+'s build plaform. It appears to be exactly 1:1.

127836

In this case, I saved out two .stls from Modeler and imported them both to PreForm's build space. I used the default placement decided by PreForm but you can position and orientate the items however you want of course. You could save it as one .stl but you'll have more flexibility in finding optimal placement and orientation if they're imported as separate objects.

I don't think I'll bother printing this but it really should work. Well, maybe not in this orientation unless you make drain holes for the shapes. But it's probably better to flip it on the platform and have the software generate appropriate supports.

G.

Greenlaw
04-12-2015, 02:46 PM
Oh, I forgot to mention something important:

I'm using PreForm 1.3. I noticed that the latest is 1.8.2--I'm downloading it now.

Also, I'm using Lightwave 2015, not 1.6.3, but I don't think there have been any changes to the native .stl exporter since 1.6.3. Just to be sure, I'll try 1.6.3 in a bit--I imagine it should work fine since the problem was apparently with the mesh, not the software.

G.

Greenlaw
04-12-2015, 03:02 PM
One last update: I got the same results using the native .stl exporter in 1.6.3, and importing the object into PreForm 1.3 and 1.8.2.

So it's the geometry. Just select the band of polygons where the gap is (use the right-arrow to select the loops,) then hide all the other polygons. Next cap the ends of each loop where the gap is (select a couple of points on the edge, press right arrow, then 'p'. Repeat for the other cap.) Select the two caps and use the bridge tool to seal the gap between the caps. Finally, un-hide all the polygons and you should be good.

Before exporting, I suggest positioning the parts inside Modeler so that the pieces may be easily manipulated in PreForm. I also recommend exporting this particular object as two separate files. You can load both into PreForm at the same time and print them simultaneously--this is how Sparklepus was printed, as three separately loaded parts printed in one pass. Printing can generally go faster if you keep the height minimal.

Good luck and let us know how it goes.

G.

spherical
04-12-2015, 04:22 PM
I agree! Here are two separate files. One is the original STL (saved as .lwo) which I downloaded from Thingeverse (I believe).

Ah... Thingiverse, the perennial source of Borked models. I'll take a look at both.


It's a solid mesh of a rain drop. The other file is what I want to achieve. It's the same rain drop however I hollowed it using the boolean function and cut it into two separate pieces (again using boolean) because I need to open up the inside.

Why do you need to open up the inside? Doesn't your slicer do skins on solids, thereby making a solid have a wall as thick as desired from a solid model? Way more efficient because you can specify Loop numbers to control the wall thickness.


(there seems to be some problem uploading them via the attachement, so here's a dropbox link):

Probably not in the list of accepted file types. Just zip them in the future.

spherical
04-12-2015, 05:33 PM
Okay, I see the problem. There's a narrow gap that circles the inside of the drop. The volume needs to be completely sealed to be valid for printing. You might be able to fix this using the Bridge tool? Just a thought. I'll see if that works.

Yes. This is indicated by 256 Edges on only 1 polygon. Cannot have that, Edges on anything but two polys, 1 or 2 point polys, or points on 0 polys. Consult the Statistics panel for these and fix/get rid of them. For some reason I cannot find, when trying to Boolean the original it reliably crashes Modeler when using the Boolean tool. Using Speed Booleans, it works. Go figure....

So, here are a couple of screen shots of how it loads, with the errors identified on the supplied separated model, and a solid model version that is sliced using 4 Loops on the perimeter. The inside of the printed pieces will be hollow, as indicated by the paths.

127837 127838

BTW, these were scaled at .1% from original to get to a workable size and then converted in Deep Exploration using a 1000 scale factor to arrive at an STL of the correct matching size on the bed.

Greenlaw
04-12-2015, 08:41 PM
That's pretty neat.

As far as I know--unless FormLabs added a 'hollowing' feature in the latest build of PreForm I just installed--the software doesn't hollow out anything. PreForm is just the front end printing software for the Form 1 and Form 1+. It has features specific to the printer, like finding the optimal orientation of the parts for the stereo lithographic process, generating 'Form 1 friendly' inner and outer supports, estimating the amount of resin needed for the print, and it can try to do some simple fixes on its own, but it is not designed to perform any substantial edits to meshes. The software will inspect your mesh and report problems but the expectation is that you have already validated the mesh elsewhere.

I guess since I only used the printer for my own meshes, I haven't run into issues like this before. For hollowing out my meshes, I just use the native tools in Modeler or 3DC, and so far PreForm has accepted anything I've dropped into it (mainly toy figure prototypes like the ones shown earlier.) But I'm curious about the software you're using, especially if it can save me time prepping and validating meshes. Is that a commercial or open source program? Thanks for any info.

G.

AlexV
04-13-2015, 02:49 AM
Wow.. I totally missed that gap. The bridge tool worked fine indeed. No importing problems in Preform either! Thanks for the help Dennis! This ended up being too easy..

Alex

spherical
04-13-2015, 03:46 AM
But I'm curious about the software you're using, especially if it can save me time prepping and validating meshes. Is that a commercial or open source program?

It's commercial, but only for the Pro version, which unlocks a few enhancements. Pro license is $42 (the answer is always "42") for life, so a great deal. Be aware that it is not forgiving. It requires clean, sound meshes. Many people start whining that the model they got from Thingiverse slices fine in but KISSlicer (http://kisslicer.com/) keeps throwing errors and won't slice it. GOOD! The reason is that the other slicers aren't smart enough to recognize that there [I]is something wrong with the file. Doesn't make it better, just clueless. I appreciate the mesh analysis in KS, as it helps me to become a better modeler by locating cruft that I didn't know was present. Some of my models have been extremely complex and KS took me to task in correcting the errors; mostly caused by Boolean operations on a very dense mesh. My, and other's, answer is always: "If you have a slicer that works for you, use it, don't try to dumb down this one."

Note that the original incarnation of KS was as its name implies, Simple. No bells, no whistles, ran on the command line. It no longer is and really should be renamed. Features are great but, just like Chuck's Software Developer's Dilemma: The better the new feature, the more feature requests it will generate., you'd be amazed at how lazy some people are; with the trivial sounding ("It will be easy to...") but actually complex stuff that they ask someone else to create for them (they have no idea how to code, so have zero clue what is involved), so they can have their life their way... for no extra money.

AlexV
04-13-2015, 04:19 AM
Why do you need to open up the inside? Doesn't your slicer do skins on solids, thereby making a solid have a wall as thick as desired from a solid model? Way more efficient because you can specify Loop numbers to control the wall thickness.


I seem to have missed all these replies. You guys have been busy :).

The reason I want to open up the inside is because it's part of a project which will end up as a "trophy" for AA members who have been sober for over a year. it symbolizes "the last drop" and the drop itself will be filled with whiskey. I can hollow it using all sorts of programs like Meshmixer, however, Preform thinks it's an intelligent program and makes the stl solid again when there isn't a drain hole. otherwise uncured resin will end up inside the print. So making it hollow can be done by creating a drain hole or by making it into two separate parts. In this case two separate parts is the way to go as I can sand the inside of the drop to make it glass-like on both the inside and the outside.

Unless you mean a slicer tool in Lightwave (which I have never used before), there isn't one in the Preform software. Like Greenlaw mentions; it's a very basic program built just for orienting your part for printing.

That program you're using seems very interesting though. I'll check it out. It'll probably save me time and frustration in the future!

Greenlaw
04-13-2015, 09:08 AM
Unless you mean a slicer tool in Lightwave (which I have never used before), there isn't one in the Preform software. Like Greenlaw mentions; it's a very basic program built just for orienting your part for printing.
Actually, I think PreForm is a slicer. Sorry, not being an expert, I'm not 100% sure of the terminology, but my understanding is that a 'slicer' is any software that can generate slices from volumetric geometry. In the case of 3D printers like the Form 1 and Makerbot, a slicer program preps the mesh so that it can be printed layer by layer, which PreForm does for the Form 1 when you send the file. But you're right, PreForm is very basic by design--it's only meant to process an imported mesh in an easy and direct manner, and any mesh editing you need to do has to be done elsewhere. (PreForm can do some fixes on its own, and it lets you know when it can, but I wouldn't rely on it--IMO, the resin is too costly for that level of trust.)

BTW, (Alex, you probably know this already and I'm only writing for completeness now,) you can see a simulation of how the software will slice your geometry by dragging the bar on the far right up and down. It's useful for optimizing orientation for printing but it also just looks cool too. :)


That program you're using seems very interesting though. I'll check it out. It'll probably save me time and frustration in the future!
I agree! I'll have to check it out when I get back into 3D printing later this week.

G.

spherical
04-14-2015, 01:03 AM
Ok, some basic terminology needs to be addressed.

A slicer doesn't "prep the mesh", the mesh is unchanged. It looks at the shape, adheres to preferences you set as to what to do with it, and then disassembles the model into discreet sections that are deposited successively in order to reassemble it in the printer. It's a bit like a transporter that takes you apart here and puts you back together again somewhere else.

For this to be successful, the mesh needs to be clean, so that the algorithm doesn't become confused and calculate paths that are not what is intended or, at the worst case, make zero sense. This requires models that are known as "watertight"; one outside, one inside, no holes, no overlapping polys.

By "holes" I mean no missing polys, not bores through an object that their surfaces are indeed still on the "outside"; even though they go through the part. The part in question had missing polys. Those are holes in the mesh and are not good, whatsoever. Why? Because the slicer then cannot tell what is and is not the outside. Essentially, it then thinks that the object is a Mobius strip; having only one surface. You can readily see that this is a problem.

All editing needs to be done "elsewhere". A number of people have complained that KS "needs" to have editing capabilities. Uhhh, no, it doesn't. That is what modelers are for. Each to its own purpose. They even complain that it is "too hard" to orient a part on the bed and that finer control needs to be integrated into the slicer. Again, uhhh, no, it doesn't. Think ahead juuuuust a bit when you are in the modeler and orient them there, where you have much finer control than a slicer can offer. Kinda duh.


The reason I want to open up the inside is because it's part of a project which will end up as a "trophy" for AA members who have been sober for over a year. it symbolizes "the last drop" and the drop itself will be filled with whiskey.

Wow, that seems really risky. When I quit smoking many decades ago, I actually went out and bought a carton and put it in the back of my Corvette. It is wherever I am, so the nicotine would be, too. It was an act of planned defiance against my "devil side". I beat myself up whenever I felt the urge and that mental act dissipated the urge, all on its own. But, I'm not the norm. I am very happy to testify that I threw that carton away many months later, unopened. I'm not sure that most would be able to stand up and be strong in the presence of temptation that is right in front of them. Props if then can.


I can hollow it using all sorts of programs like Meshmixer, however, Preform thinks it's an intelligent program and makes the stl solid again when there isn't a drain hole. otherwise uncured resin will end up inside the print. So making it hollow can be done by creating a drain hole or by making it into two separate parts.

Yep, all manner of programs think they're intelligent and know what you want.

Two separate parts is the default way to go in most printers, as there need be no support structure for overhangs... because there aren't any. I get that Form 1s can get away with less or no support, where what I call non-slury printers need it. Still, thinking ahead and looking at the overall picture is best, no matter what slicer you use or printer type you may be running.


Unless you mean a slicer tool in Lightwave (which I have never used before), there isn't one in the Preform software. Like Greenlaw mentions; it's a very basic program built just for orienting your part for printing.

There is no slicer tool in LightWave. Not its purpose. The question is, will PreForm accept G-code generated externally or will it think it "knows better" and restructure it? I'm guessing the latter, as it builds parts inverted, so a +Z slice may not work. Then again, it may, the build plate is just upside down so +Z == -Z and all's good.

AlexV
04-14-2015, 01:52 AM
Ok, some basic terminology needs to be addressed.

A slicer doesn't "prep the mesh", the mesh is unchanged. It looks at the shape, adheres to preferences you set as to what to do with it, and then disassembles the model into discreet sections that are deposited successively in order to reassemble it in the printer. It's a bit like a transporter that takes you apart here and puts you back together again somewhere else.

For this to be successful, the mesh needs to be clean, so that the algorithm doesn't become confused and calculate paths that are not what is intended or, at the worst case, make zero sense. This requires models that are known as "watertight"; one outside, one inside, no holes, no overlapping polys.

By "holes" I mean no missing polys, not bores through an object that their surfaces are indeed still on the "outside"; even though they go through the part. The part in question had missing polys. Those are holes in the mesh and are not good, whatsoever. Why? Because the slicer then cannot tell what is and is not the outside. Essentially, it then thinks that the object is a Mobius strip; having only one surface. You can readily see that this is a problem.

All editing needs to be done "elsewhere". A number of people have complained that KS "needs" to have editing capabilities. Uhhh, no, it doesn't. That is what modelers are for. Each to its own purpose. They even complain that it is "too hard" to orient a part on the bed and that finer control needs to be integrated into the slicer. Again, uhhh, no, it doesn't. Think ahead juuuuust a bit when you are in the modeler and orient them there, where you have much finer control than a slicer can offer. Kinda duh.

Point taken! I understand what you mean completely!


Wow, that seems really risky.

Very true. This was asked by the chairman of the AA-meetings. The drop will be enclosed in another printed cage though. And resin is not suitable for food/drink consumption. Nevertheless there are indeed some desperate figures for whom it might be too tempting. Therefore, I am talking to them to replace the whiskey with tea, as no one would be able to notice the difference!

This is what they're aiming for:
127856



Yep, all manner of programs think they're intelligent and know what you want.

Two separate parts is the default way to go in most printers, as there need be no support structure for overhangs... because there aren't any. I get that Form 1s can get away with less or no support, where what I call non-slury printers need it. Still, thinking ahead and looking at the overall picture is best, no matter what slicer you use or printer type you may be running.

In case of the drop I would be able to print it without supports, but in most cases, the Form1+ being a resin printer, supports are definitely needed.


There is no slicer tool in LightWave. Not its purpose. The question is, will PreForm accept G-code generated externally or will it think it "knows better" and restructure it? I'm guessing the latter, as it builds parts inverted, so a +Z slice may not work. Then again, it may, the build plate is just upside down so +Z == -Z and all's good.

Unfortunately, you're right. The Preform software does not recognise G-code. But Kisslicer is definitely a good way to check an STL for errors. Like you mention. Thingiverse is "the perennial source of Borked models" ;). Sometimes it's just easier to refer to a borked model rather than to model a new one yourself. So Kisslicer is a great tool to help in the process.

spherical
04-14-2015, 03:22 AM
Very true. This was asked by the chairman of the AA-meetings. The drop will be enclosed in another printed cage though. And resin is not suitable for food/drink consumption. Nevertheless there are indeed some desperate figures for whom it might be too tempting. Therefore, I am talking to them to replace the whiskey with tea, as no one would be able to notice the difference!

Good approach. It is, after all, a symbolic gesture.


Unfortunately, you're right. The Preform software does not recognise G-code.

Then it might be a good thing to interest a coder in developing a converter/plugin/whatever for Preform to allow it to just pass G-code through. It's the proprietary thing all over again. 3D Systems Borged Bits from Bytes and killed a really good pair of printers, then used the basic design of the Pro-level one and made the CubeX out of it; complete with even more restrictive proprietary filament cartridges that cost ten times market and an encrypted build file format to boot. Didn't take long for the userbase fed up with the crappy prints to develop workarounds that allow use of industry standard code and materials. 3D Systems are Jerks of the highest order.


But Kisslicer is definitely a good way to check an STL for errors. Like you mention. Thingiverse is "the perennial source of Borked models" ;). Sometimes it's just easier to refer to a borked model rather than to model a new one yourself. So Kisslicer is a great tool to help in the process.

Heh, some of the models that I have had the displeasure of fixing would better have been started from scratch.