Topic: 3-D software

[greenjeans]

Any 3-D guys out there ?   I hope to have access to a CNC for a month coming up and would like to do a project.
Anyone have any 3-D experience ?  Is there any FREE software worth a try ?     

[calj737]

What are you trying to create?

[eigenvector]

No, but I would love to hear some suggestions for a home user.

I know the stuff we have at work - but I don't have a spare tens of thousands to spend on CAE software.

[greenjeans]

What are you trying to create?

Trying to create a tank/seat/tail section for a project I'm working on.  It will be fiberglass - I plan on making a plug (which would be 3D modeled and cut) from which I'd make a mold to make the body piece from.  My hope is to be able to make 3 or 4 of these on the cheap.
I tried with some rigid foam insulation it wasn't getting the  angles I hope to get. Figured if someone could help me along with the 3D modeling (I've never worked in 3D software but am pretty good with vector 2D software

[BomberMann650]

If you're going through the trouble of cad designing the piece.  Why not have the 3d printer cast you a finished and paintable seat?

In the time this thread has existed.  Could have been well into sculpting a foam mould by hand.

[RAFster122s]

Your 3D model program/software has to be able to run through a converter or it be imported into a program to generate the G-code a CNC machine uses to cut and machine the part.

Another option, make your model in foam and have a 3D scanner scan the part, it can then be post processed to generate the 3D printer input needed.

The challenge you face working in foam or wood to create the model is that of symmetry.  If you use templares from side to side you will be able to maintain that symmetry from side to side or front to back is much easier to achieve.

Think about the problem in a different manner... what do I mean?  If you section a model or a part into cubes or slices you can achieve symmetry easier. If you know the shape/profile of the beginning and end of a slice you can often connect those two sides with a straight line. Those that are are a contoured or a curved transition from one edge to the other.  From side to side you mirror the profile...since most tail sections and seats will be symmetrical from side to side.
You can cut foam with a hot wire, stainless steel fishing leader with a couple amps at 12V is capable of cutting blue, pink, or white foam used in home construction as insulation.  An insulation supplier often stocks building material foam.  Dow (blue) Formular comes in a few different densities, they have a 150 and 250 version  are different weights and the texture becomes finer...  they both will sand very smooth with coarse to medium sand paper as well as Surfoam "plane" which is made by Stanley and is like a cheese grater.  You can rough form large pieces with the Surfoam products but, if you cut the part through a series of slices assemmbled and glued together in a stack. In that case you would skip the Surfoam planes and go to sandpaper.  When you cut those sections to cut them a tad oversize to sand to profile and transition between slices smoothly.

Just some input if you want to do it manually...




arediffernt weights and textures. They will

[calj737]

What are you trying to create?

Trying to create a tank/seat/tail section for a project I'm working on.  It will be fiberglass - I plan on making a plug (which would be 3D modeled and cut) from which I'd make a mold to make the body piece from.  My hope is to be able to make 3 or 4 of these on the cheap.
I tried with some rigid foam insulation it wasn't getting the  angles I hope to get. Figured if someone could help me along with the 3D modeling (I've never worked in 3D software but am pretty good with vector 2D software

Well, for an education, "3D" isn't what you want. You want a "surfacing" product to deal with the complex curves and organic shapes (unless you're planning on a very rectilinear part). So things like SolidWorks and other "solid modeling" products are out. Alias, AutoStudio, Inventor all can be used. you can take these drawing files then import them into (via STEP, IGES, DXF) into most CNC programs. It won't create the final and complete G-Code, but it does provide the operator a huge head start.

3D scanning is very costly. It also requires that your part be "accurate" so as not to require modification afterwards. Scanners are best used to "recreate" an existing part that's already been machined, cast, or produced.

[RAFster122s]

Oddly enough, our local library has a free 3d scanner and to print you pay by the filament cost...
But, as Cal has pointed out, you will only be able to print that part or if generating gcode from it modifications are going to be a challenge or impossible. 

Students can get free 3 yr licenses for a product like autodesk fusion 360, a monthly subscription for typical license is typically like $25/ month for subsciption or $40/ month for month by month license.  It can do everything from creating a 3 d model to generate and manipulate the Gcode for various cnc lathes, mills, etc.
But this may not be the best tool as Cal has pointed out...
Free software solutions are often not without their limitations or

[Jore]

Download Fusion 360, it does all you need and has a bunch of good tutorials on youtube.

[greenjeans]

I tried using some pink rigid foam on my first attempt.  My problem is:  I have a lot of angles and indents.  I just couldn't get the hard lines that I want.  Realistically, I did not think about it enough before starting.  I've started another attempt, and am getting closer, just not where I want it to be.  Then, I found out the place I work has a 4'x8' router/cnc table.   It's really not a true 3D machine as it cannot rotate.  But, it can do topographic type work.   It also seems like fun.  By using it, I'd definitely have a easier time getting it more symmetrical.   I do have 3D printers in the same shop, but the size is limiting.  It would be awesome if we had one that were big enough to make the mold.  That would really speed me up.

[BomberMann650]

I tried using some pink rigid foam on my first attempt.  My problem is:  I have a lot of angles and indents.  I just couldn't get the hard lines that I want.  Realistically, I did not think about it enough before starting.  I've started another attempt, and am getting closer, just not where I want it to be.  Then, I found out the place I work has a 4'x8' router/cnc table.   It's really not a true 3D machine as it cannot rotate.  But, it can do topographic type work.   It also seems like fun.  By using it, I'd definitely have a easier time getting it more symmetrical.   I do have 3D printers in the same shop, but the size is limiting.  It would be awesome if we had one that were big enough to make the mold.  That would really speed me up.

When it comes to art/design - there is ongoing philosophical debate over hard line symmetry.  Our brains rational mind likes it, the creative mind is somewhat ambivalent.
The mathemeticians can write the equation for a perfectly sculpted form.  While the artist can work without such convention.  Our brains adapt to both.  Though it had been noted that certain overly rigid designs can make some viewers internally uncomfortable.
As if it is too perfect for the brain to accept.  Then there is the contrast.  Where we can readily accept some imperfection and our brain subconsciously fills in the beauty we want to see.  As is the case with many things found in Nature.  We often see a pinecone as symmetric, when in reality, that's not entirely true. 
So there is a holy grail to be found somewhere in the middle.  Where rigid convention and organic form fuse into a shape that boths sides of our brain finds pleasuring and desirable.

[RAFster122s]

A wire brush in a dremel will create a pink snowstorm of foam as it brushes away foam.  It makes quite the static mess but it works quite quickly at shapind, albeit with a dished cut.  Rough shape by cutting close to final form, shape with sanding blocks and rods with sandpaper and the dremel, just do not try to make a smooth flat surface or smooth rounded surface with the dremel unless you have a very very steady hand.  You shape it roughly to shape and final sand it to shape with various blocks, wedges, rods with sandpaper glued to them with spray adhesive or rubber cement or wrapped around them, whatever method works well for you.

Spackling compound will stick to the foam as will plaster to fill or smooth areas.  Water based acryllic wood working finishing material like polycryllic can seal and provide a glossy smooth finish befor applying pva to make your mold.

You can work in small sections of the overall part.  If you mess up an area you can cut out a square block with a hacksaw blade and carefully sand to fit your replacement block and glue it into place with white gorilla glue you mix up witha bit of water int a cup to make it foam up a lot.  Use this foamy glue to glue in the block.  Premixing with water expands it and makes it a lighter consistency so it is not as hard a glue .  Avoiding a hard glue will allow you to sand these areas without fighting the hard glue line and getting a raised line wher the glue is and dished areas on both sides where the foam cuts away from the glue so easily.

You can use masking tape over areas you do not want sanded when doing final shaping or as you are shaping.