3d models to shopbot advice

[fearstyle]

I am a 3d modeler at heart and I am in the comp art department at School of Visual Arts / Fine Arts. We just got ourselves a huge shopbot and I have some experience sending 3d models off to a shopbot now, I know a buddy who has one and has done things for me on small scale from 3d models in halves like a face ect. While sending a 3d object to be milled from a solid material like that is one thing, what im looking for is some advice or tutorial on taking something pratical like a desk modeled in 3d and blowing it apart to make actual pieces to create tool paths with and cut from various materials to make those parts.

A Simple example would be this simple render of this desk Or even better yet a simpler design of a traditional desk perhaps. Point is it’s a solid single model and want to go from that to building independent parts and tool paths to send to a shopbot without too much fuss .


6554

Right now I do most my Modeling in Maya while I am working on buffing my skills in studio tools, know my way around Max as well. Just sat down with rivet but have not had the time to really explore just yet.

Can any one point me in the right direction?

[tgm]

"...Point is it’s a solid single model and want to go from that to building independent parts and tool paths to send to a shopbot without too much fuss"

The above statement is easier said than done and would be the 'Holy Grail' equivilent to anyone running a CNC. To get even close to what you are looking for plan on spending $15-20K for just the software and even then you won't get what you asking.
Designing on a screen is one thing, producing the parts in an efficient manner is a whole other ball game.

Good Luck.... and if you do come up with a way that works you will never have to work again!

Tom in PA

[fearstyle]

I beg to differ... I mean there has to be some thing out there that has some automation. I know many cad applications have exploders built in as well. http://laminadesign.com/ would be a example of what im talking about. I see a lot of designs posted in 3d like the desk over here: http://www.talkshopbot.com/forum/messages/312/16678.html but seems like he modeled it as each piece is its own mesh object resting against each other vs a single mesh object like the desk i posted.

Point is im not working in AutoCAD or ArtCAD where there normally are explosion tools or un-wrappers from my understanding, im working in Maya some thing that does not have the tools to explode a 3d model since its geared differently. wonder if studiotools has a unwrapper for cuts..

Guess what im asking is how does one go about dicing up a object mesh when its a single object mesh and not each wall its own object mesh.

[kirkkelsey]

We are currently doing our woodworking design in the 3D solid parametric modeler Alibre Design, outputing DXF files of each part, nesting with MasterCAM and producing them on the ShopBot.

Alibre Design is an affordable parametric modeler similar to SolidWorks and Inventor, much in favor with engineers that do independent consulting on the side. The price of Alibre Design ranges from $500 to $1500, with yearly maintenance of only $295. You can however start with the free Alibre Xpress version. There is no time limit, only a 10 UNIQUE part limitation.

We like doing solid modeling with Alibre as it is like virtual woodworking, where you create each part similar to how you would manufacture it. It allows us to dry run the construction, as well as run an interference check on the completed model. The main thing to remember, is one part per part file, and then put the parts together in an assembly file. The Drawing and Bill of Material is all derived from the solid model, which can be used to create DXF files and cutlists. The parametric capability of Alibre allows us to use formulas to drive cabinets and have all the cabinet parts resize with a simple change of the cabinet width value.

Alibre is a great way to create parts for the ShopBot and woodworking in general. Hobby woodworkers are thilled with using the Free Xpress version. We have worked our way up to the Expert version with 3D PDF export capability, rendering and motion simulation. You can upgrade as your work and income justifies the purchase.

You can manually nest parts using Alibre, and output a DXF that can be imported into the control software for cutting.

In our case, we needed an even more efficient workflow and purchased software to do our nesting. We looked at ArtCAM Cabinetmaker, Enroute, MasterCAM Router, and even AlphaCAM. MasterCAM best suited our needs. This is the software that will set you back as it it priced from $3500 to $5000 plus first years maintenance. Yes, you can get Automatic Toolpath Nesting of sheet material for only $5k, it is the fancy milling that costs even more. It may seem like an overkill, but the company we are currently working for was going broke spending $5k in labor every couple of months to go from designs to ShopBot code. We can now take a completed design, and nest the DXF files for an entire kitchen and produce the Shopbot code in about an hour and a half (including manual code review).

Visit our website www.kelseywoodworks.com and download the video tutorial on how to design a Keepsake Box in Alibre, as it is a good overview of how to use what is normally a mechanical design package for woodworking. Also, visit www.instructables.com (http://www.instructables.com) and look through the CAD group for tutorials we have posted on woodworking techniques for Alibre Design. We are not Alibre sales reps, just users with the same enthusiasm for our design software as most ShopBot'ers are for their machines.

We have found our Holy Grail, but now we are even busier than ever creating designs and producing code.

[jeffreymcgrew]

I'll second on the Alibre thing. That's a great little tool.

Our holy grail is Revit + Artcam Insignia. We model in Revit, which lets you cut clean sections and views of the models to get clean DXF outlines of all the parts. Those are exported to Insignia where they are nested and toolpathed and then cut on our PRT96. We an go from custom design to cut file in no time at all.

With your Maya work you'll be able to follow a similar workflow actually. What you'll need to do however is figure out a way to cut sections of your models in Maya and get clean, dimensionally accurate, orthogonal DXF outlines of those parts. Can't you instance elements in Maya, so that changes can 'echo' automatically? Maybe with a series of views and layers and instanced copies you could easily isolate each part in it's own view. Then you could export those views and pull them into Partwizard even and manually nest them.

As for something that would automatically take a multi-part solid model and explode it and generate the code to cut those parts, as was stated above that's going to cost a bundle. It is out there, but I'd work at figuring out a way to do what you're after with Maya first just with cutting sections, isolating parts, and exporting...

[robtown]

Scott, I use 3dsmax a lot in the things I do. What you will find is that if you build it in 3d as if you were building it for real the process is a lot easier.

What I mean is that it's simple enough, or maybe not, to make a 3d object, texture it, light it and render it, but it's not real in terms of how it might be constructed physically in the real world.

Take your desk that you pictured, looks awesome, but it's probably a shape that's been extruded and some boolean operations for the drawers. To actually make that desk you'd need a face, a back, some ribs and internal structure that you can wrap bender board around, etc... I don't know of any software that extrapolate that info from a 3d model and make the process easy or simple. What will make it simpler for you will to build it using actual construction methods that you will have to comply with in the physical world. Save all shapes you use in your extrude and loft operations and export those as .ai or .dxf/.dwg.
That desk and stool is just a bunch of ribs with a face and back, then veneer applied...

Basic point I'm trying to make is learn about how things are built.

Don't know if this helps at all.

[tgm]

All the above points are valid for the various reasons stated. We too, in our business,use multiple programs, as Kirk does above, to accomplish our production issues on a day-day basis.
As Rob and Kirk both state all the parts have to designed individually, at some point in the design process, before you can even think of producing them on any type of equipment.
To say you want to do a rendering and then output directly from that rendering is not going to happen,without someone at some point, designing how the part is actually made up of component parts.
As Rob states above, learn how things have to built and use that as a basic guide as you design the final product. More than one product has collected dust on the shelf when it was found out that it could not be made or was too expensive to be made as designed.
Your on the right track.....stay there.

Good Luck,

Tom in PA

[dray]

Sorry, I am not up with all the 3d software.
I am a cabinet builder. You can take the front shape of the desk and chair and turn it into a dxf file and simply size it and cut it out.

Then the radius ends can be made of bendable birch.

That cabinet should take about 3-4 hours to complete w/out stain etc

[mrgadget]

Kirk Kelsey is featured in an article in the May issue of Wood Digest. Great article, and congratulations Kirk. I just broke out the magazine this morning and scanned through it and then was reading the forums and here he was again!

[kfitz]

Scott,

As Rob, Danny and others have pointed out, the desk in the example above is not a candidate for 3D machining with a ShopBot. It is simply a collection of 2D parts that are assembled together in such a way as to have 3D properties when finished. Export your geometry as 2D parts, cut and assemble.

-Kevin

[tgm]

Kevin,
Scott did not want to machine in 3D, he wanted to export his 3D model to a program that would then machine the parts, the parts of which have never been thought of, let alone designed.
Scott mentions the program Lamina, which is intended to take a 3D model, composed of surfaces, and then flatten and export the dxf's for those surfaces to be machined. The basic underlying difference here is that those types of shapes are hollow and most don't depend on a frame or structure to support them, which is where all the extra parts come in to play.
Bottom line, you have to design thinking from the inside out.
As they say ..'you can't get something for nothing' and this is the classic case. Doing the 3D design is the fun part of a project, then you have to say to yourself ..'now how do I build it??'

[fearstyle]

Let me ask you guys another question. Lets say im modeling a polygon model in say maya were i can export to a few standard options. What would be a good way to slice that model up to say mill it out of foam in layers to assemble later.

[Brady Watson]

Vectric's Cut3D: http://www.vectric.com/WebSite/Vectric/cut3d/c3d_index.htm

[kfitz]

Rhino works well for slicing solids into sections. You can get a free, fully functional (25 saves) copy at www.rhino3d.com (http://www.rhino3d.com).

[kirkkelsey]

Alibre has just released a new Xpress Plus version for $249, that includes 4 video training CD's and a 30 part count limit, rather than the 10 of the Free version. Training is the most important aspect, and it is included with this package.

But, since you are in school and can take advantage of the great Academic pricing on software, take a look at SolidWorks, and the academic video training bundle from Solid Professor. Go with what industry is using and the software that will be best on your resume. There are great prices online, but your school may offer even better deals.

I am a strong advocate of Parametric Modeling software due to the flexibility it offers with the ability to use formulas to define part sizes and inter-relationships. At least go with 3D design software as that is the future.

Alibre is what I can afford, but I think the free version will handle the needs of most people quite well. Great for creating vectors, 2D DXF files, and doing manual nesting for the ShopBot.

[paco]

One very cool thing about slicing in Vectric Cut 3D is that the software will create his own file format with the slices and when those are open in Cut 3D, it will machine only the side and not the top (where it's actually the material surface). This can save quite a few hours of machine time... few CAM do that... most CAD will slice the model as basic feature.

Tony's Cut 3D slicing trick; if, for some reason, you decide to slice your model in CAD (http://picasaweb.google.com/the.real.paco/CEGEPDeDrummundvilleMiniBAJAProjects/photo#5057145748410172370) (I once did that for nesting the slices in sheet good), you slice your 3D nested slices model with a thousand less than the slice thickness so that Cut 3D will make you a no-top-to-machine-slice (http://picasaweb.google.com/the.real.paco/CEGEPDeDrummundvilleMiniBAJAProjects/photo#5057145744115205042). Say your slices nesting is 1 inch thick, slice it in Cut 3D with a setting of 0.999".
This would be an example. (http://picasaweb.google.com/the.real.paco/CEGEPDeDrummundvilleMiniBAJAProjects)