Is my 3D model structurally stable? This is the first 3D model I have ever created.

[Anonymous]

Hello,

I was wondering if anyone could take a look at the test tube rack that I designed and let me know if it seems stable.

I have never used Fusion360 before, so I am not sure if there are any small errors that could cause the structure to collapse?

I am having it laser cut soon, so I just wanted to check.

Are all of the angles, lengths, and sizes correct? Or is there an error that I am missing?

The file is in the comments.

Thank you for any help you can provide in advance!

[Anonymous]

Here is the Fusion 360 file and the SVG file that I will send to be laser cut.

Feel free to provide any feedback that you can.

[jhackney1972]

You have designed you model without capturing design history so there is not much to look at to determine "how" you modeled it.  As far as the structure, the vertical height is not very strong due to the fact that you only have four narrow edges, two at the top and two at the bottom, preventing it from folding up.  Put a slight bit of force on the top front edge and it will fold up like a deck of cards.  If you close in some or all of the sides, you will create a box structure that would be resistant to this issue.  That is my opinion.

From now on, as a new user of Fusion 360, you should enable Capture Design History so you can see your timeline making it easier to modify and enhance your designs.

[Anonymous]

Hello!

Thank you so much for this advice! Yes, I agree with you. Originally I had the sides closed up, but because it is a test tube rack, I was asked to remove these side walls so that the test tubes could be grabbed. 

The only forces that will be applied onto the rack will be from within each hole (as beakers/test tubes are placed inside). Do you foresee an issue with this kind of use? Sorry if this question is too vague to answer.

Thank you for you rhelp!

[jhackney1972]

I have already offered my opinion.  There are other methods of adding strength to the structure besides closing in the sides.  Maybe a diagonal brace, laid in to the verticals in an attractive manner. 

[TheCADWhisperer]

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@Anonymous wrote:

Here is the Fusion 360 file and the SVG file that I will send to be laser cut.

Feel free to provide any feedback that you can.

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I assume the material to be used is wood - you might get away with zero clearances between mating parts as most woods will readily compress, but I think I would design in clearances for ease of assembly.

[Anonymous]

Sorry, I should have been more clear about what the material would be!

I completely understand why you assumed wood, but it will actually be plastic (acrylic). Do you foresee any issues with that? Sorry if the question is too vague.

[TheCADWhisperer]

Include a bit of clearance between tabs and slots.

I would also chamfer after cutting, but not sure if you want the chamfers in the model.

Also - your components do not seem to match up correctly (Side and Middle).

Toggle visibilities on/off for each.

And turn on you Capture Design History.

In fact - I recommend that you start over with History turned on for practice on this easy design before you get into more complex designs.

[Anonymous]

How much clearance would you recommend between the tabs and slots? I was hoping that it would fit tightly to make it more secure. But I think I am misunderstanding something, how will the clearance help?

I'll ask the laser cutting place about chamfer! Thank you.

Where do the Side and Middle not meet up properly? I've been toggling the visibilities but I cannot see the issue. Sorry if I am missing something obvious. If you mean that "Middle" also includes one of the sides, that is an error that I got from the template that I used, sorry about that, should have noted it in the original post.

I will definitely use Capture History in the future, thank you! I'm just trying to meet a deadline for now, so I cannot start over today, but in the future for practice I will try.

[etfrench]

The orientation of the model looks wrong, so I'll assume the View Cube back view is actually the top.  If you intend to glue these pieces together, then it is more than strong enough.  If you're not gluing them, then there isn't much holding the parts together.  Adding clearance without knowing what the fit is, could result in it not staying together.  In addition, if you're not gluing, then adding small side pieces with tabs will help hold it together.