Friday, August 31, 2012

Spiked Pendants

While trying to come up with some new ideas for things to make I was doing some fiddling and a couple of things popped out at me. A couple of pointy things. Both are now available in my shapeways shop.

And here they are...

The Ring of Spikes Pendant.
Circles or Rings typically represent eternity or the life cycle.
But, to me, this one appears to be holding something at it's center.
Something invisible, something tortured. Some poor trapped soul.
Could be part of a great Halloween cosume. Or, just wear it if that's your style.
It still looks cool. Even if I made it sound creepy.

Then there's The Inverted Half Mace pendant.
It appears normal from the front. But, when you take look at the back. There are more spikes inside.
They feel like they represent the internal struggle that is being human. As we hide ourselves from the world, this mace hides its spiked internals from the viewer. Only the wearer knows its true identity.

I hope you like them, and thank for reading!

Tuesday, August 28, 2012

Using reference parts in assemblies

Just a quick tip for anyone who uses Autodesk Inventor for Shapeways 3d printing.

In an earlier post. I showed how to set up your part or assembly templates to give you an estimated cost without having to upload your file to shapeways.

I recently worked on a project that required I include a part that I didn't want printed.
I needed to use as a reference in the assembly so that I could build around it.
By right clicking on the part in the browser and choosing "Reference" in the "BOM Structure" menu. The reference parts volume is excluded from the estimated cost! Very handy! Well, at least I thought so ;)

Be careful though. You will want to suppress the part or toggle visibility of those parts off before outputting your STL file for printing. Otherwise they will be printed, and that's not what you wanted.

Thanks for reading!

Friday, August 24, 2012

Dragonfly is ready to prototype.

I realize this has been a long and drawn out process. But, it's finally ready to prototype. Here's a video of the final model in motion.

I have two concerns about the final product.
1. Will the wings be heavy enough to fall back down on their own. Or, will the holes be too tight and hold the wings up?
2. Will the lip and snap fit prongs on the cover and the base be loose enough for it to fit, but also be tight enough to hold it closed? Only the prototype can tell me that.

Building a better dragonfly

After finding the worst possible way to get my dragonfly body from Sculptris to Autodesk Inventor,  and then finding a slightly better way. Inventor was still choking on the geometry. It could handle it, and it looked decent, but it was still causing performance issues on my weak sputtering old pc. I learned that if I made nurbs in 3ds Max. I could export them as an IGES file and inventor would take them in as if they were their own. It would love them and hold them and happily stitch them to a solid with no resistance, no long waits, no CPU spike, no whirring chewbacca fans blowing smoke out the back of my tower.
 The file size is only 200k, rather than the whopping 30-40mb of the previous methods..

Here's what it looks like now.

I first learned that exporting IGES files would preserve the smooth surfaces from inventor and import them into 3DS Max as solid bodies. So, I wagered that the opposite might be true as well. I decided to try it out, and it worked perfectly. With a small win under my belt, I set to find a way to salvage what I already had made in Sculptris. I made some attempts to find a free program that would convert the geometry to a nurbs surface and save it as an IGES. However I kept finding the same answers over and over. 100s of posts in dozens of forums, and the same advertisers saying... "Our product can do that! Come buy it!".
No free lunch today it would seem. Coincidentally, I skipped lunch today so I could write this.

With no free lunch, and nothing to make my sculpted body play nice with inventor. I decided, to scrap it. I started a brand new body made from actual nurbs inside 3ds Max. It wasn't as easy as sculpting. But, it wasn't horribly painful either. All in all, it wasn't a bad first experience in 3ds Max. The only down side I could see was that the nurb editor felt a lot like a plugin. Something that got tacked on afterwards.
That lead me to believe that maybe there was something else I should be using. So, I did a little digging again, and it was looking like Rhino or Maya were the nurb editors of choice. But, nothing free. Except blender. Once again I hear the murmers of the web telling me "blender can do that".

Now that the body is finally finished I can perhaps get onto wrapping up the wings, and the project in general. Here's a video of the project in its current state.

Everything is complete now except the wings.
They look a bit too much like butterfly wings, and not like dragonfly wings. I'd like to fix that.

Standard issue poly/quad meshes like the ones made in sculptris are perfectly good and are a more than acceptable method of producing geometry for 3D printing. But, unfortunately Inventor seems to hate them. Inventor specializes in designing "feature driven" models. Cutting and welding and folding, hole making, etc. So, when it comes to designing moving parts within the tolerances set forth in shapeways design guidelines I feel very comfortable in Inventor. But, for the organic stuff, it's less than ideal. If you plan on importing something into an inventor project that is organic in nature. It looks like designing it with nurbs and exporting as an IGES file is the best way to go.

Thanks for reading!

Saturday, August 18, 2012

Sculpting and Inventor

So it's been over a week now and I've only begun to scratch the surface of interoperability between inventor and other non-native 3D formats.
I've found that there is a way to get objects from Sculptris into inventor. But, it is not the optimal way of doing things. The objects are very very facet heavy and inventor buckles under the weight of all those facets.
So, rather than posting a "how to" on placing memory hogging faceted objects into Inventor. Instead I will share what I learned that led me to finding another, better way of getting organic sculpted shapes into inventor. 

After a week of research i found myself feeling a bit foolish. The Autodesk Product Design Suite that i've been using has Mudbox as part of the package. So, I've been sitting on Mudbox this whole time. Sculptris is still great, but since Mudbox is part of the suite, i should probably be using it. Plus, it does have some pretty neat features. like sculpt layers.The workflow for moving the sculpted data between Mudbox and Inventor is totally ridiculous for a suite. Not much better than just using Sculptris and Inventor. Although, who in their right mind would be using Mudbox and Inventor at the same time? Just us Dr. Frankenstein types I guess. Anyway, let's get started.

There's 2 to 3 additional pieces of software needed to make a round trip from Inventor to Mudbox and back.At the bare minimum you will need
1) MeshLab,
2) AutoCad
If you have 3DS Max, there's some benefit to including it in the workflow. but for sake of simplicity we leave it out of the equation for now.

In the world of 3D there are a number of different types of objects.
The two we will be dealing with are Solids and Meshes.
Inventor creates and wants Solids.
Scluptris and Mudbox create Meshes.

I'm not going to pretend that I know a lot about 3D Meshes, because i don't. But, in their simplest form they are a series of points (vertexes) in a 3 dimensional space connected by lines (normals).
These vertexes and normals typically create a series of polygons or triangles that can be used to create a surface. In some cases the lines may be straight which creates facets (this is what inventor chokes on), but in other cases they may be curved to give smooth appearance to the model. Someone can correct me if I'm wrong but I believe the curved ones are called NURBS.

The second entity is the Solid. Solids are, or can be, a lot like meshes, with one important difference. The mesh that creates them is closed and filled with imaginary matter. Imagine the earth with the longitude and latitude lines painted on it. Those lines represent the mesh. The mesh is fully connected to itself. It doesn't detach at any point and drift off into space. It is a grid that is closed and connected to itself which creates a "water tight" surface. Beneath that surface is the soil, which makes the earth solid. Like the earth, any object that has a "water tight" mesh can be converted to a solid.

So, now that I've explained what we're dealing with here. Here is the workflow.
For additional detail, I've done video tutorials for both Part 1 and Part 2 of the workflow.

Please excuse the sound quality. I was using headphones for a mic, and I was a bit stuffed up from allergies.

Part 1: Inventor to Sculptris.
1) Export base mesh from inventor as an STL file.
2) Import STL into MeshLab
3) Export from MeshLab to OBJ.
4) Import OBJ into MudBox or Sculptris
After doing your sculpting in Sculptris or Mudbox  you can move on to getting it back into Inventor.

Part 2: Sculptris to Inventor
1) Export new OBJ file from Sculptrix / Mudbox
2) Open OBJ in MeshLab
3) Export from MeshLab as 3DS
4) Open AutoCAD, and set your environment to 3D Modeling
5) On the Insert Tab, choose Import and select your recently exported 3DS file.
6) Move to the Mesh Tab, and choose "Smooth Object" or type in CONVTOMESH
7) Again on the Mesh Tab, choose Convert to Surface or type CONVTOSURFACE
8) Save as DWG (2010 version).
9) Import DWG into Inventor.
10) Use the stich tool in Inventor to stitch the surfaces into a solid.

The videos are worth taking a look at, particularly for Part 2 of the workflow.
There are some choices to be made in the import and export dialogs which are explained in the video which may not be obvious at first glance.

Thanks for reading!

Monday, August 13, 2012

Tutorial coming soon...still

My journey over the last week or so since first stumbling upon Sculptris has been long. My original goal of writing a tutorial on how to get Sculptris objects into inventor turned out to be more challenging than I initially thought. Not because the software is bad, but instead because I lack basic knowledge of 3D object types and file formats. But, I am getting closer. The more I learn, the more I feel that I should be focusing on learning blender in the nearest future. It's beginning to seem more and more that blender is like the Swiss Army Knife of free modeling software. It's not a cannon that obliterates projects from miles away. But, with some know how, it will get you through the wilds. At least, That is the impression I get from people out there in the wilds. As I travel the web in search of all the mysteries that are 3D, I keep hearing "blender can do that".
I will post my tutorial soon but it may not be exactly as I had planned it. It may be something a little different.
In the mean time, seek inspiration!

Thanks for reading :)


Tuesday, August 7, 2012

Sculptris is SICK! and FREE :D

Note: Thanks to Mezmera for pointing out that this software is Mac/Windows only,
No Linux based version at this time..

So, the other day, I saw a post in the shapeways forum saying how easy this software was to use. I thought to myself...3D is never really easy. There's always navigation controls to learn, then a whole slew of primitive shape tools, then even more tools to manipulate those shapes...the list goes on and on. Boy was I wrong.

The software was called Sculptris from pixelogic It's not real stable on my old clunker of a pc. But, neither is flash player or even Firefox for that matter. A faulty surge protector and a few power outages will do that to a PC. Probably the coffee maker too (is that why it's been tasting burnt lately?)
But, that's besides the point.
It's a small download and it installs in a jiffy. The interface is minimalistic and intuitive. My initial reaction, is that this software is what most software should be. Fast, powerful and easy to use. Not to mention its free.

Without reading or watching a single tutorial. I was able to make this creatures head shown below in less than 10 minutes. NO EXAGERATION!!. That's just plain awesome. It was almost easier than if I was using real clay. I'm blown away. I can't believe this is free software.

It was almost as if it knew exactly what i wanted it to do.

You can even paint and texture it. (See the red eyes!)

Plus, you can export the 3D mesh as an obj file, along with the texture and uv maps for use in other applications. I couldn't ask for more. Except a better pc to run it on. I'm not worthy! (Wayne's World reference, anyone catch that?)
You must check this software out for yourself to experience its awesomeness.
Here's a link to the download page for it.

I'm still working on converting the resulting meshes/obj files for use with inventor. perhaps that will be another post for another day.

Thanks for reading!

Sunday, August 5, 2012

Back to Moving Forward

I had fun doing the ring designs.
I have quite a few models stocked up but nothing worth sharing at this time. Maybe later this week, but not today.  If you have no idea what i'm talking about, I'm talking about 3D printed objects. If you can design it, they can print it in 3D at There's some limitations of course, but you get the idea.
Something else has moved to the front of my priority list. That item, is the fact that I would like to get a few samples ordered from Shapeways soon. They say a picture is worth a thousand words. Pictures are something that my shapeways store is lacking. I need to show some actual finished products on there.
So, if I'm going to be placing an order. It seems like a good idea to wrap up one of my moving part projects so that I can get a prototype of one of those as well (save some $$ on shipping I hope).
Since I'm going back to one of my moving parts projects. I'll share it with you.

I wanted to make a dragonfly that flapped its wings. Seems simple enough, Right?

Here's a screenshot of the miniature as it stood this morning.
I didn't completely plan out the linkages that will move the wings yet.

I know that doesn't tell you much. So, Here's a screenshot that shows the internals of the base.
Two gears, with 8:1 gear ratio. The idea was that 1/4 turn of the main gear would give the dragonfly wings a good flapping or two. 

But, it's proving more complicated to model than I initially thought. I should really have planned out the linkages.But, that's what I get for jumping in head first. So, after half a days work, i find myself with what looks like a finished product.. But, doesn't function like one.

The wings will flap. But, not as I had intended them to.
So, it's back to the drawing board. This time I will plan the linkages first.
I believe some bevel gears are in the future of this project.

I also had the idea of making a small vehicle that ran off a wound up rubber band.
That seemed like it might be fun, and much easier to model. But, where's the fun in that?
You won't learn anything taking the easy way out. We only learn from our mistakes.
So, the lesson here... Plan your linkages!

When I have the final product ready i will share it.

Thanks for reading!

Wednesday, August 1, 2012

1 million polygons served...or less.

So, today I learned a little bit about the file size limits on shapeways.

As an Autodesk inventor user, typically to export for shapeways i would go to...
Print->Send to 3d print service.
I check the unit of measure to make sure i'm sending the right size, and set the resolution to "High".
Click "Okay", and save the resulting STL file.

Up until today, I had always done smaller single object files.
Today I wanted make a multipart STL that was a batch of objects connected with sprues so that it could be processed at one items. This is what sent my file over the limit, and this was new territory for me.

At my current employer, all our files sit happily on the server and they only get opened in inventor.
So, if I can make it in inventor, then everything is a-okay. I don't have to worry about file formats or size or resolution or anything at all really.

In the 2D world of printing, I'm very comfortable. So much so that I authored a new set of guidelines for my previous employer, who had as many as 20 designers pumping out files much larger than they needed to be. But, that's all in the past. Here in the future, in the world of 3D, I've heard of some formats and I've heard of some software, but I have little experience. So, it looked like it might be time to do some research.
Well, like a typical guy, i knew enough to be dangerous, so I opted to not read the instructions and just started trying things.
The results were good. I didn't have to stray far from my old ways to do what I needed. The 2d world taught me that I can reduce file size if I sacrifice quality. So, the first thing I tried was reducing the resolution of the STL from high to medium. Out of curiosity i decided to press the print preview button.
Which to my delight showed me a preview of the resulting mesh, the resulting file size, as well as the polygon count. It still looked great, the facets were well above the level of detail i needed, and my file size was below the minimum now too. So i'm good to go now. Right?

WRONG... I was over the maximum polygon count for shapeways. The max polygon count is 1 million triangles. Lucky for us, inventor tells us in the preview window exactly how many wer're using right there in the print preview window. So... i tried again. This time i chose a custom resolution and set the "surface deviation" to something slightly higher. My polygon count went down even more. One more tweak to the surface deviation and i was good to go. My file was under the max file size, had less than 1 million polygons and still was an acceptable looking mesh. Now, what i need to do is get a prototype made at this resolution.
I'd like to see how the printer interprets this new resolution when it breaks the mesh down into layers of printed material.

Thanks for reading!