Why is my tool not going on my model edges?

[kcn94]

Hello all,

I'm quite new with Fusion 360 and I've a problem that I can't resolve despite having fiddled with several settings: My tool, when generating the path, doesn't go on my model edges, leading in my final milled model being almost 5mm too short on X and Y.

Here is my model, front view of the edge:

And here is where the tool is milling, missing the edges:

My form is a hole in a piece of wood (cabinet door) that I'm trying to recreate and as you can see, the final result is too short as expected, some milling is missing (only check on the Y, the X is smaller on purpose):

What can I do for the tool to really take all the piece into account when generating the toolpath?

I'm milling with a 3.2mm bit with 0.1mm height steps.

My model is 4cm height but my final milled piece is only 3.5cm height.

Thank you all for your help!

[jhackney1972]

Please attach your model so the Forum users can take a look at it.  If you do not know how to attach your Fusion 360 model follow these easy steps. Open the model in Fusion 360, select the File menu, then Export and save as a F3D or F3Z file to your hard drive. Then use the Attachments section, of a forum post, to attach it.

[kcn94]

Hello,

Please find the model attached.

Thank you for your help! 

[jhackney1972]

I do not have a lot of experience using a Mesh as a model for manufacturing but two things hit me.  One is that your model has errors in it as indicated by the "!" in the screen capture.  The second thing is I think I would use a Bounding Box for my geometry selection instead of Silhouette.  My model is attached.

[kcn94]

Thank you, I'll have a look at your model and report back.
The "!" doesn't matter I think, it's just because my mesh isn't closed.

[kcn94]

It does the same, missing the edges, it should really cut on the edges, not miss them like this and now it creates holes where it shouldn't:

Can you tell me what you modified exactly? I can't seem to see it.

You just went from Machining Boundaries - Silhouette to Bounding box?

Because that's what I had before, but then I had the same result as above: holes where it shouldn't.

Might be because my mesh is not closed but I'm not sure, I'll try to close it properly and export it again.

I'm also wondering if I didn't "break" something in the settings because I fiddled with a lot of them without really knowing exactly what they would do, maybe the fact that the tool doesn't go on the edges is linked to one of those settings I touched?

Thanks!

[kcn94 · Accepted solution]

I think I figured out what happens. My steps are 0.1mm (the minimum step my 3D Printer can make) and my mesh is so precise that it just can't mill the edges as seen in this picture (the first green line is the first 0.1 step so everything on its left won't be milled):

So I cheated, I made my original mesh 5mm bigger and I'm now milling it, let's see if I managed to get those 5mm lost back.

[kcn94]

Well it worked, my Y is now 4cm (3.5 before). It looks a lot more like the original one:

I cannot say it is fixed, because, well, I cheated, but I'm pretty sure that the 0.1mm step limit was the culprit here.

Thank you @jhackney1972 for your help!