Is this design possible in Fusion 360? Which tools would be used to make this?

[michaelkelly7104]

Hello everyone!

I'm looking to make something very similar for a family member's birthday as I know they love their audio and this looks like something special, however I can't get the smaller cylindrical section to follow the larger cube section with an equal wall thickness. I'm also struggling with the shape in general, and ultimately pretty lost. So far I've managed to loft out the port of the speaker, however using this method, as mentioned before, I can't get a consistent wall thickness, or the consistency in general of the speaker in the picture.

The attached image shows the design I'm trying to replicate.

Can someone advise as to the best tools/parameters in the model section of Fusion 360 to use here?

Thanks!

Michael

[TrippyLighting]

That Grovemade speaker was in fact designed in Fusion 360.

I would not consider this to be a beginner project, however.

[michaelkelly7104]

Thanks for your reply - that's interesting! Do you have any advice with regards to which tools would be utilised within Fusion for this?

[TrippyLighting · Accepted solution]

The exterior might be a T-Spline or a loft in the Patch workspace.

The interior is also likely a combination of lofts in the patch workspace combined with section cuts for the stepped appearance of the air channel/horn.

Depending on your experience in CAD and other 33D modeling software this may have made little sense to you. 

[michaelkelly7104]

Thank you Peter - I will explore tutorials on these tools and see where it takes me. My experience is fairly basic, though I have used Fusion for about 6 months for simple projects. I've done one prior double sided machining project so I'm fairly confident I can make that work, along with the tool-paths - it's just the design side that's getting me here!

[chrisplyler]

I doubt they modeled the interior "stepped" appearance. I strongly suspect that's just the result of milling out the interior with a large-ish endmill (for the lower cavity) and a ball-end mill (for the upper cavity).

[davebYYPCU]

Big call, 

article says so in black and white....

[michaelkelly7104]

Thanks for your replies - this makes things quite a bit simpler, however - would this change the tools (within Fusion) involved in making this?

[TrippyLighting]

What makes you believe that this simplifies things ?

[chrisplyler]

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@davebYYPCU wrote:

Big call, 

article says so in black and white....

---

The article says that they modeled the interior steps and flutes? I certainly don't find that language.

I see pictures showing foam prototypes with a much smoother internal appearance. I watched the video, which shows in COLOR, various prototypes upon which different tools and tool paths were obviously chosen chosen, various hand finishing of the exterior but not the interior, their actual mill with tools in it, and even a view of their model on a laptop screen.

The interior steps and flutes are quite obviously the result of doing 3D Adaptive CAM strategies with high step-over values and tool sizes. In other words, the model had a smooth interior, but they intentionally made no effort to clean out that extra material. It's a nice design choice I think, but my "big call" is obviously correct.

[ToddHarris7556 · Accepted solution]

+1 for @TrippyLighting's suggestion - this is likely to be a lofted interior. In speaker design, the shape & size of the horn section along the length are key design factors. I think it would be easiest to control this with a series of sections that could be precisely manipulated, then lofted to create the cavity. 

On a different note (as pointed out in the article) the stepping is just a balance between production speed and non-value-added surface finish. i.e. if the customer can't see it or hear a discernible audio impact from the outside, then there's really no point in machining it smoother. 

[michaelkelly7104]

Less steps I guess. Ba-dum-cha! Thanks for all your help!

[michaelkelly7104]

 Thank you for your reply Todd. Is there a way of maintaining the wall thickness with a command or otherwise? I notice there's a great deal of consistency in their design that would be difficult to achieve without maths. I'm familiar with dimensioning within fusion, but unsure of how to achieve that level of consistency?

[TrippyLighting]

Wall thickness can be maintained by shelling or offsetting surfaces.

[ToddHarris7556 · Accepted solution]

Yes.... what @TrippyLighting said.

For a product like this, I would envision a workflow something like this (admitting that I'm an engineer, so I tend to think function>form. It's also completely possible the designers cared more about form, and jammed the functionality into the available space):

1) Start with the engineering of the inside cavity. Optimize the speaker horn path using a series of lofted sections, and wrap them into a compact shape.

2) Using this interior lofted shape, offset construction surfaces out to get the minimum wall thickness. 

3) Using those construction surfaces, create the outer surface that's more pleasing/flowing/stable. 

There are probably a handful of different detail-level approaches - some people might use T-splines, some more surfaces. As I mentioned, you could probably attack this in reverse : start with a desktop footprint, and work your way in, fitting speaker components in the available cavity.

[michaelkelly7104]

Thank you both, I really appreciate your help. I think I have enough information to make a good start here 🙂