3D Tool path Parallel issues

[abadsvt]

Hi Everyone.  I am new to Fusion and Cam.  I have successfully cut a hand full of item on my cnc mill using 2d tool paths. Worked great.  Very straight forward. Then i got an idea to "Engrave" designs on the material.  Was wanting to do cross pattern design using 3d Parallel tool path.  Creating small rectangle tool paths.  I was wanting to cut .03 deep into the top of the part with this design.  I can get the cross pattern tool paths to show in cam but they don't actually cut the model during simulation.  Even when the bottom heights is set to model bottom.  It shows the tool path ramp up the side of the model but it stays perfect flush with the top of the model.  Hope that made sense.  It should be cutting through the stock for example if the bottom heights is set to model bottom.  I am just playing with a 2" wide x 4" long x .5" thick stock sample.  No special design.  I feel like i am missing a button to click or something like that.  Any ideas what is going on?  Thank you ahead of time!!

Josh

[LibertyMachine]

Please export and share your file. We do not have enough info to go on to help you further

File > Export > Save to local folder. Return to thread and attach the .f3d file in your reply

[johnswetz1982]

The parallel toolpath is doing exactly what it is supposed to. A parallel toolpath will only surface the top of your model surface. It will also try to get to the sides of your model, that is what you are seeing with it diving over the sides. It is a finishing strategy. I think you would want a 2d or 3d adaptive roughing strategy. You can try an example of adding a boss or projection from your surface to see that parallel is doing what it should.

[LibertyMachine]

You say " I can get the cross pattern tool paths to show in cam but they don't actually cut the model during simulation"

But then say " I am just playing with a 2" wide x 4" long x .5" thick stock sample.  No special design."

Do you have a cross designed inside that stock, or are you just trying to face the material?

[abadsvt]

Thanks guys.  I think possibly an easier way than have you guys look through my model is explaining how the 3d tool path Parallel gets its finish depth of cut height.   The stock heights tab has Model Bottom as its bottom height setting but if you just click ok and generate the tool path it is on the model top surface.  Does that make sense?  Does it use the model top as its finish cutting height?  If that is the case i would need to have stock left to machine the parallel tool path.  I don't see an axial depth of cut in any box during the setup of the 3d parallel .  Did that make any sense?  Thank you for your help.  Really loving Fusion just get stuck every now and then.

Josh

[LibertyMachine]

A) The file aids more than most people realize. Often new users are trying to do something that could be much more easily solved with another method, or perhaps they are trying to do something that isn't even possible, but they don't know it yet, based on where they are on their CAD/CAM journey

B) Any of the 3D toolpaths (typically) will not violate the model. You can tell it "model bottom", but it won't intentionally cut through more than you want (not considering the bugs that are cropping up now and again, those are separate issues)

Your toolpath is looking for a surface, you have given it that with the top portion of the part. Your selections and other settings dictate where the tool goes. But, since we don't see your settings or selections..... 🙂

[abadsvt]

Thank you for all your help.  I have attached the file (hopefully i did this right :)) .  You can see how the parallel tool path doesn't actually cut any stock.  I believe i have it setup so after the facing operation it leaves .002 stock on the top of the model.  Then when the parallel tool path starts it should be cutting the .002 stock left on the top but it doesn't appear to do that.  Really appreciate any help you have.  Thank you.

Josh

[johnswetz1982]

A couple points and suggestions. You probably want your work origin something other than stock, I would suggest corner of model or model top center. For your facing op you can leave bottom height to model model and just turn on stock to leave. The reason your not seeing any crosshatch pattern is because the cusps left over from you parallel toolpaths are only .002 tall. You check the z coordinates of your tools in the 2nd simulation tab. If you want the crosshatch pattern like the attached image you need to leave more stock for a bigger cusp.  

[LibertyMachine]

Yup, as @johnswetz1982 stated; leave more material on your Facing operation.

3D Toolpaths can be made to ignore the model, but this is bad practice and will likely result in a serious crash at some point if you aren't at the top of your game

[abadsvt]

Thank you guys for the help.  That makes sense.  I was probably going to use an actual engraving tool or spot drill to do the cross hatch design on my part.  Good suggestion on the orgin location.  Ill switch that that . Thanks again.

Josh