[jmc2010]

I'm new to MadCAM and CNC in general, so go easy on me. I'm working on cutting a pocket for some inlay work, and am doing two passes to complete the work. One with a .125" endmill, and the final pass with an .0625" to clean up the corners. The process is working well, except that the final pass takes forever, most of which is just air cuts, since the roughing removed all of that material. Is there a way to setup my process so that madcam will know what was taken care of on the initial roughing pass, and skip that work on the final?

Thanks,

Jason

[svenakela]

I can tell directly right now that you are doing things wrong, and your process is not working so well (as it should).
You are not using roughing, Z-level and Planar combined, right?
Because if you do, your roughing will take the big thing, the Z-level and Planar will do the finishing without running in the air.

Did you read the tutorials and watched the movie-clips? I am pretty sure you can speed up things.

[Dan B]

If you could provide a couple of screen shots of your model, showing your paths, or better yet, post the file, and we should be able to help out. Sven is right, you are definitely doing something wrong. Pocketing in madCAM is very efficient if you do it right.

[jmc2010]

You are not using roughing, Z-level and Planar combined, right?

No. I was simply using what I knew would work, which was the "pocketing" under 3 axis profiling and pocketing. I didn't want to venture too far out into something that I didn't quite understand. So, should I be doing:

Roughing < Z level finishing < Planar finishing

In that order?

Did you read the tutorials and watched the movie-clips?

I have watched quite a few, but its been hard to tell what order to watch them in and what applies. Maybe I will just watch them all today.

[jmc2010]

If you could provide a couple of screen shots of your model, showing your paths, or better yet, post the file, and we should be able to help out.

The model is at the other office, but I may be able to get it sent to me. I'll upload it as soon as I have it. Really appreciate the help.

Jason

[Dan B]

If it was me, I would do it all as 2D curve machining. Once we see what you're working on it will be a lot easier to come up with a strategy. Off the top of my head, I would use Pocketing and follow up with a Profiling path to finish.

[jmc2010]

Here you go. I had to zip them up to attach them. Also, there is two files, but they are both the same model. Just different actions in each, as I wanted to make sure that I could post process them separately to avoid a tool change in the middle of the file.

[Dan B]

Okay, thanks. I'll take a look. FYI... you control what you post by use of layers. If you don't want a path to post, shut off that layer. If you want all your paths concatenated, then leave them all displayed. Works that way for the simulator too.

[Dan B]

Yes, as suspected, you are cutting air with the second path because you are using Pocketing again. The bigger cutter has already removed the majority of the material. I would use Profiling for the second tool and only cut what's left on the walls. If you have material on the bottom, you can clean it up with pocketing, but change the depth so it only does one pass. A trick I use is to add whatever stock you are leaving on the sides to the depth. That way the roughing tool will finish the bottom of the pocket. Then you can walk around with a profiling tool and your pocket is done. I usually set my profiling depth to the bottom and control the step down by varying the ramp angle. You get a nice spiral path doing that. Change the ramp angle to change the depth of each pass.

[svenakela]

I would do it either of these these two:

1. Pocketing, leave a 1/10 of material if this is wood. This will act like a roughing.
2. Contouring of all the pockets, will be your finishing pass of the sides.
3. Set the Clipping Plane to -0.1 and -1.0
4. Planar Finishing, with Contouring option. This will be your bottom finish.

Pros of this approach are Probably faster machining time as it is only a 2D operation and if it is going to be repeated it will save some time.
Cons with this approach are that you must now the depth of the pockets and you have to reproduce all steps for each pocket (otherwise you will get travels you might not want).


I would prefer to do it this way:

1. Roughing, leave a tenth if this is wood.
2. Z-level
3. Set the Clipping Planes to -0.1 and -1.
4. Planar Finishing with the Contouring option clicked.

Pros: Just make the paths. No need to know the depths. Way faster to set up than pocketing.
Cons, Might give you some unwanted travels in the roughing. Can be avoided by doing roughing for each pocket with a region curve.

I would easily go for the second option if you are making a few of these. If you are mass producing, gor for the first option.

[jmc2010]

Thanks for the suggestions, guys. I'll be trying to some of them out in the morning. I played around with the model a little bit tonight, and set it up with a roughing pass, and then z level finish followed by planar finish. When I posted it, it said that it was about a 45 minute process. Probably about the same as the first way I did it. Its hard to know without much experience what the settings should be on things. Like the z level finishing has a step down of .251mm. That seems so small. The cutter is a .0625 2 flute end mill. That is only about 1/6 of the diameter of the cutter. Is that right?

[svenakela]

Change the values after your own needs The default values are there to give a starting point and a glossy surface... ...in metal.
I think my approach was about 6-7 minutes cutting time.