[Cb750r]

I've self taught myself a lot of programs, however I'm struggling with this software package. I want to use this mainly for the CAM, I've been using Meshcam on my home brew TAIG CNC mill , but looking to see if stepping up to a more robust CAM solution is going to help.

OK rant over, Question one, can someone point me in the right direction for creating a boundry or a way to tell bobcad not to machine the whole stock?? I'm working with a simple triagular shape, and don't see the need to rough out all the excess material on the outside when working on a triangular shape.

how would one accomplish creating a work holding tab for a 3d shape. Again Meshcam makes this EXTREMELY simple, was hoping for a similar fuctionality but with more options,

Attachment 261510

[LeWhite]

No need for boundrys or tabs on that part. Drill holes and bolt to tooling plate. If you profile rough then finish you'll only have two passes. I would bolt the slug down too. Dont pocket the inside, but profile by reversing the tool path direction. On the outside use circular entry at the middle of the bottom. On the inside plunge to z 0.0 then ramp profile, remove slug, circular entry to finish. When you get better at Bob you'll feel less like a chimp at a typewriter and more like a conductor an front of an orchestra.

[Cb750r]

Good point, a rough profile is what I would like to achieve, will hopefully avoid the inlaws for a few hours today and see if I can type out something legible today!



Anyone able to point me in the right direction for how to create boundaries for tool paths? Where can I find some decent manuals or tutorials? Bobcad after dark on YouTube seems to be a bit geared towards users already familiar with the system.

[hkenuam]

You could just do a parallel line or use offset to create a boundary around your part slightly larger than the diameter of the tool you intend to use to control the toolpath but for me, a part like this I would just use 2d tool paths. if you are holding it in a vise the center section might be an extra step to plunge a drill in or endmill to get rid of the center material and then just 2D Profile (Contour Ramping) both inside and out, then flip it over in a set of soft jaws and mill of the area you held it on. Thousands of ways of course this can be done but I've made a ton of these parts (usually just 1 - 5 ) and it's the fastest in my opinion.

Hope this helps

[jrmach]

Documents & Manuals | Software documentation BobCAD-CAM | BobCAD-CAM

[mmoe]

I've self taught myself a lot of programs, however I'm struggling with this software package. I want to use this mainly for the CAM, I've been using Meshcam on my home brew TAIG CNC mill , but looking to see if stepping up to a more robust CAM solution is going to help.

OK rant over, Question one, can someone point me in the right direction for creating a boundry or a way to tell bobcad not to machine the whole stock?? I'm working with a simple triagular shape, and don't see the need to rough out all the excess material on the outside when working on a triangular shape.

how would one accomplish creating a work holding tab for a 3d shape. Again Meshcam makes this EXTREMELY simple, was hoping for a similar fuctionality but with more options,

Attachment 261510

I own Meshcam (bought it for processing speeds on a specific type of job) and use Bobcad for most things, so I can understand why you are having trouble. They are very different systems that don't share much in common at all. The thing is, you're going to have to forget what you know about Meshcam when doing things in Bobcad because it will only make it harder if you are trying to apply what you already know to Bobcad.

There are several things about Bobcad that are significantly different, and one is the strategies you have available. For a part like the one you are showing, it's not really what we'd call a "3d" shape since it can be cut using 2d strategies alone. Meshcam doesn't have that option, so you're used to doing what are essentially work-arounds to cut a 2d part with 3d strategies, since that's all that Meshcam has. With Bobcad, you don't need the 3d strategies for this part, and in fact the 2d strategies are optimized to do what you want much more efficiently. I can't quite tell the scale of your part, but I drew up a similar shape to show how I'd cut it out. You'll see that with 2d strategies, there's no need for boundaries. Tabs are unfortunately the one option that Bobcad has still not provided in the basic system. It's been requested (probably the most requested feature) and I'm told they are working on it, but for now the only ways to get tabs out of Bobcad is to either buy Bobnest or to draw in line segments and generate a toolpath for the tabs separately from the rest of the part.

In the video I show using the 2d pocketing strategy to clear out the middle. It works similarly to the roughing you used, but you are keeping it just inside the selected pocket area. It also has a finish pass automatically added to the process, though you can skip it or customize it even further by adding or removing strategies. For the outside, I show using the 2d Profile strategy using the "Side Rouging" option to remove a little more stock to start with than a single roughing pass would. You could do it with a single roughing pass as a ramp spiraling around the part, or you can do multiple depths of a single pass for roughing as well. No matter which way you go, you can then follow up with a finishing pass to clean it up. Again, you'll find that there is no need for a boundary on a part like this because boundaries are more for 3d objects or parts that require 3d strategies where you want to contain the strategy to an area of the part. Even for parts that are "3d", you'll find that you often need to use a combination of 2d and 3d strategies to get the part done right.

Here's a link to a quick video. I didn't do the drill op as I think that's more obvious to figure out. If you have trouble with it, let us know and people here are happy to help. What you'll notice with Bobcad is that most things require using the "right-click" of the mouse. If I'm selecting the perimeter of a part for a 2d operation, I hover over the edge until it highlights, then right click to bring up the option for "constant Z", followed by selecting that option to create a continuous loop of geometry. You could also individually click each edge, but there are ways that can cause mistakes (sometimes you'll click on something behind what you see and don't realize it). When you finish selecting, you again right-click anywhere on the blank portion of the screen and choose "OK". For settings in the CAM tree, you right click on portions of the tree to bring up options.

https://files.secureserver.net/0sVhp2bvEWAsad

Another thing you'll see in the video above is that I set up the Work Offset in my machine setup. This is specific to my machine simulation, and you only need to use it if you are simulating with a full machine. If you use one of the built in mills, for example, choosing the top of the stock as the origin as I did in the video could cause the stock to be inside the table during the simulation. You may need to offset the simulation by the thickness of the stock (+12.7mm in the example) to bring the stock to the top of the table for simulation. If you have a vice modeled, you may need to make it even higher to get it in the correct position in the vice. Point is, you can ignore the Work Offset settings if you aren't simulating with a full machine. They do not affect the code generated. In my case the numbers I entered are very similar to the numbers I enter at the controller on the actual machine, though the Z value varies a little depending on how far into the collet I install the bit (I use work offsets instead of tool length offsets to set my Z).

[Cb750r]

Wow great post thanks will review and report back on my next trial!

[jrmach]

Here is a file in V26,,ask questions if need be

https://www.youtube.com/watch?v=lEHu...ature=youtu.be

[jrmach]

For a part like the one you are showing, it's not really what we'd call a "3d" shape since it can be cut using 2d strategies alone.

Tabs will be drawn in 3D wire frame as my example shows.Will be machined in 3D wireframe as well


The way I got my geometry for pocketing was I created another layer and extracted edges from the solid.
I also used those edges to to an offset and get the geometry for the 3D wire frame.
If you need help with 3D wire frame ask,maybe I will video it

[mmoe]

For a part like the one you are showing, it's not really what we'd call a "3d" shape since it can be cut using 2d strategies alone.

Tabs will be drawn in 3D wire frame as my example shows.Will be machined in 3D wireframe as well

This can work pretty well, but takes some extra setup time in creating geometry. I also use the 3d wire frame feature for more advanced 3d lead-ins where plunging is generating too much heat (plastics) and spiral is not quite right either. 3d wire frame works well for very special needs and is a very powerful strategy.

I have Bobnest myself, and the advantage there for tabs is that you can still do a roughing and finish pass with all the bells and whistles of the side roughing and lead-ins just as you normally would. The downside to Bobnest is that it's a real pain to learn to control in terms of positioning the part, and it's really somewhat confusing for the beginner. The cool thing with Bobcad is that there really is a lot of ways to do just about everything you may need to do.

[mmoe]

Here's a quick video showing the use of boundaries in true 3d situations. I also show the use of the "DMS" system where you can customize the toolpath strategies all in one list. In this case, I just added Equidistant Offset to a Z-Level roughing. Sometimes it's better to keep the strategies in their own separate feature, but other times it's more convenient to combine them into a single feature. With the latest Bobcad releases, you can just use geometry right off of the part to create boundaries. While I did not use the option, you could also extract the edges of the solid and project them to a Z-plane above or below the part, then use the geometry as a boundary or even offset the geometry to create a larger or smaller boundary. There are also quite a few options in the Equidistant Offset strategy that allow you to be very specific about where in that boundary you cut. You can have the tool inside, centered or outside of the boundary, or you can specify the top/bottom most Z level to finish, or you can isolate only areas within specific angle ranges. So the boundary is only the first step in determining the limits of the toolpath and you can be much more specific than that if needed.

https://files.secureserver.net/0sWYq3aD3KuvsZ

[jrmach]

https://www.youtube.com/watch?v=j8OA...ature=youtu.be




There are certainly more than one way to do these things as you can see

[Cb750r]

Hey Guys I really appreciate all the input. I have to admit I tried again with using 2d profiles like suggested and after several attempts of ot producing code to mill out the part instead of the stock I downloaded a trial of a much simpler Cam program and was able to create a full 3d two sided part and I'm pretty darn happy. I will see if this project has given me enough to springboard up to Bobcad, but right now it looks like Cambam might be my new Cam solution.
Below is a link to my dual edge safety razor head I designed and milled out of aluminum.

Instagram