[dogmaphobic]

I'm obviously new to all this. I've being playing around with a Sherline mill, so far having no problems cutting away panels using CamBam. I now however, had a first actual 3D part to mill and I can't quite find a way to deal with it. Over the past month or so I've downloaded and tested just about every CAM software that is available for download and test (which, by the way, made me think they are all stuck in 1985). None of them could deal with something I would think is the next simplest thing to mill after cutting panel holes. I'll try to attach an image of the (very simple) part I'm trying to mill. If I load it as a 3d part (stl file for the packages that can actually load it), they all assume the stock is one rectangular piece of metal and spend a great deal of time milling away nothingness. That is, the part is L shaped and I precut the stock so to it is roughly the proper shape. None of the packages will allow me to define the stock other than x,y,w and h. Is there something that doesn't cost the price of a small house that would do this efficiently and simply?

Thanks!

[Geof]

For something that simple why don't you learn how to hand code it?

[Ron Dunn]

Is that really a 3d part?

It looks like a 2.5d L-shaped part to me.

I know VCarve can do this, I would be very surprised if Cambam couldn't do it the same way. Only the sharp inner corners would have a small radius, depending on the tool used.

[dogmaphobic]

Your suggestion is perfectly valid but it feels to be the equivalent of you having asked what program would help you add a series of numbers and I told you for something that simple, you should write your own code in assembly language. Is hand coding gcode the way to go?

Why can't a program figure out the piece of geometry you loaded has a large void around (z = depth) and create a profile tool path around it instead of milling away volumes and volumes of stock, layer by layer until z = depth? This ought to exist. I was just hoping someone would know and point me to the right direction.

Thanks!

[Ron Dunn]

Please refer to my message about 2.5d vs 3d.

2.5d will do exactly what you want ... create a profile, then mill around it.

Here's a simple example from Vectric's Cut2d product. Look at the filter plate half way down the page. Isn't that similar to what you are trying to do?

Cut 2D - Overview | 2D Hobby CNC Machining | Contour machining | Text Engraving

[dogmaphobic]

Ron, yes, I had seen Cut2D and it does indeed seems like it would be exactly what I was looking for. It was one of the dozen or so packages I downloaded. I discarded it because the paranoid trial version would not allow me to load my own files. Between guessing what would it do and trying other programs, I ended up forgetting about it. Thanks for pointing it out. It got lost in the shuffle due to its own paranoia.

Is that really a 3d part?
It looks like a 2.5d L-shaped part to me.

Well, I guess it's all semantics. I designed the part with a parametric solid modeling tool (Autodesk Inventor). This particular part happens to have slots and some threaded holes underneath (which will require turning it over for a second path when using a 2.5d tool) but the point is, it shouldn't matter. I know, wishful thinking...

As I mentioned, I am admittedly new to CAM, CNC, etc. so part of it is resistance to a learning curve that I feel hasn't existed in other fields for years now. Think of digital photography, audio, video, etc. These things 10 years ago were all in the realm of absurdly priced software tools (and vastly more complex than computing tool paths). Nowadays they are all taken for granted. Simple and mostly free. I guess we just have to wait a bit...

Thanks!

[txcncman]

None of the cheap software packages i have seen will allow defining a stock shape other than rectangle or cylinder. The tool path is independent of the stock shape and cutting starting point is defined in the tool path parameters. This is were knowledge and experience of the CNC programmer comes into play. If you start your cutting tool path 1/2" outside the stock or 1/2" inside the stock which results in a crash.

MasterCAM will reference a .stp file, other than your part .stp file to allow verification to show machining realistically. This is intended for working with castings or fabrications or weldments.

[blowlamp]

That isn't a 3d part, it's a simple 2d job to do in CamBam.

Try to remember that 3d machining is usually only done on curvy components - things shaped like a computer mouse or other freeform shapes such as modern cars and aeroplanes.

Draw your shape as a 2d outline and use the appropriate MOPs in CamBam to cut the profiles and pockets.
It turns into a 3d component by specifying a target depth of cut to give the part a height dimension and is really quite straighforward to do.

Read the new CamBam documentation on the website for more info.


Martin.

[ger21]

Why can't a program figure out the piece of geometry you loaded has a large void around (z = depth) and create a profile tool path around it instead of milling away volumes and volumes of stock, layer by layer until z = depth? This ought to exist. I was just hoping someone would know and point me to the right direction.

Thanks!

To a CAM program, an .stl file is just a bunch of triangular faces.

There are CAM programs than can load other 3D formats like IGES or STEP, or even some native CAD file formats, and recognize the features of the 3D models. But, get your wallet out, as they tend to be several thousand dollar packages, typically starting at about $3000 and going up.

If the top if your part is a flat surface, and the operations you need are pockets, holes, slots, and profiling, than a 2D drawing is what most people use with a 2.5D CAM program. As everyone said.

[dogmaphobic]

Learning something new every day (at a neck breaking pace at that). The question is now CAD rather than CAM. I've been designing with Inventor and that's what I'm used to. I am not however, in any way an expert. Not by a long shot. I can export the whole solid as a 3D entity, which proved to be a no go with these programs, but I can not (or could not find a way) to export an iso view as a 2D file. I can export one face at a time and then load those in CamBam but that means generating several separate tool paths and their respective nc files. Feasible but tedious.

While at it, the more I play with CamBam the more I see it as my preferred tool to get something done quickly and accurately (and thankfully it had no pictures of ghastly carved Bass or Eagles in its front page, something that made me run away from other packages).

Thanks to you all, I wouldn't be able to get anywhere this fast if it wasn't for this forum!

[txcncman]

With CAD all you get is a drawing file. CAM, all you get is an interface to create the G-code you need for the machine. CAD/CAM does both in one software package.

I used to do hand written programs using AutoCAD by getting X,Y data right off the drawing.

This is all about simplicity, functionality, ease, and time versus money. The more money you spend, the more you get. A pad of graph paper and a scientific calculator are pretty cheap and can get the job done for under $10. Takes a little longer and need a little more smarts on the part of the programmer.

Almost all of the software will do what it claims to do. Now, it is just a matter of how much you want to spend. Usually you get what you pay for. For CAD/CAM, PowerStation Pro is about $1600. PowerStation Xpert is about $800. Once per year they put both on sale for 1/2 price. For 2 1/2 D, I rank PowerStation Pro very close to MasterCAM in abilities. Funtionality, not so much as the interface has more of a DOS based feel to it being more menu driven instead of Windows based with more icons. I do have a problem with PowerStation Pro in that it has difficulties with some IGES files and will only read AutoCAD R12 DXF files. So, cross platform compatibility was an issue.

[ger21]

I don't use Inventor, but the usual process is to create a 2D drawing and save that as a .dxf file.

For that part, all you need is the top view. (The view in your pic)

[blowlamp]

If you get yourself onto the CamBam website with some questions, we'll get you sorted out

Quite a few of us use ViaCAD + CamBam and the combo works a treat for both 2d and 3d work.

Hope to see you there.


Martin.

[jhowelb]

Your suggestion is perfectly valid but it feels to be the equivalent of you having asked what program would help you add a series of numbers and I told you for something that simple, you should write your own code in assembly language. Is hand coding gcode the way to go?

Why can't a program figure out the piece of geometry you loaded has a large void around (z = depth) and create a profile tool path around it instead of milling away volumes and volumes of stock, layer by layer until z = depth? This ought to exist. I was just hoping someone would know and point me to the right direction.

Thanks!

It will. Try V-Carv ( or Aspire, just designate a profile either on, inside or outside the line) o,r if you have a dxf drawing, SheetCam will do the job.

[Aussie_CNC]

If you enjoy using Inventor, why would you not consider InventorCAM Xpress? It's a cut down (read 'cheaper') version of a much bigger package, but provides the simple tools you need to produce a tool path on your parts without the export/import hassle!

InventorCAM Xpress: InventorCAM CAM-Software

[dogmaphobic]

If you enjoy using Inventor, why would you not consider InventorCAM Xpress? It's a cut down (read 'cheaper') version of a much bigger package, but provides the simple tools you need to produce a tool path on your parts without the export/import hassle!

InventorCAM Xpress: InventorCAM CAM-Software

It does look interesting but their web site lists no pricing and I really don't like having to call to find out, Inventor notwithstanding. When I see these packages that you can't immediately order online and download, I simply ignore it.

Thanks!

[Aussie_CNC]

Ok, sorry if I wasted your time - I assumed that because you are using Inventor that you were not looking for a $200 solution.

[dogmaphobic]

You absolutely did not waste my time (what gave you that idea?) I was simply voicing my dislike of web sites that hide their product's pricing.

[txcncman]

Most of the retail side of our industry is not manufacturer/producer based, it is dealer based. The manufacturer/producer allows the dealers to set their own price points and profit margins. This is why, even though the manufacturer/producer has a web site and offers support, they do not list pricing there. If you contact them for purchase, they almost always refer you to a dealer that is most local to you. That dealer names their price. Works exactly the same for purchasing an automobile. Sure, you can call up Ford and inquire about a new truck. But they will send you to a local dealer who will name their own price. I won't argue whether this is a good system or a bad one. I will say it does give the buyer a lot more room to negotiate. When the dealer names their price, you can probably take 10-20% off and give the dealer a take it or leave it ultimatum and it is likely they will take it.

[rowbare]

As others have mentioned this is really just a simple 2.5D part. As an aside, you probably want to radius your inside corners. Round cutters have a heck of a time with square corners.

D2nc Software is inexpensive, quick to learn and does a good job for parts like this.

bob