Quote Originally Posted by dmehling View Post
No response yet? I didn't think my questions were that complicated. What I really need to know is how thin can I make my tablet holder and how narrow can I make the perimeter section and crossbeam sections. I don't know if these are the best terms, but I think the picture makes clear what I'm talking about. I am considering nylon, but since my last post, I've also been thinking about aluminum. I did several Google searches, but cannot seem to find any info as to weight-bearing strength of these materials. Perhaps I don't know the right terms since my engineering background is essentially nonexistent.
As I already said ... ABS is not a good choice : as it has a high shrinkage ratio, it warps. Since you intend to make a flat wide part, it is not a smart material choice. Tritan, PETG and nylon are Ok choices, it's mostly about what you have at hand.

Regarding why we are not giving you a solution : the results depend on several branching choices you have not mentioned. You don't need to be an aeronautics engineer to know this : you can trade thickness (to a point) for infill rates, the number of shells weighs in, sharp corners create weak areas ...
But then, your requirements are somewhat blurry. What do you want it to stand to ? What is the max authorized static deformation ... ? What is the load case ?

So, unless you ask with proper engineering parameters, you don't get an engineer answer. ;-)

As a starting point, and given the the overall idea, I would advise you to :
- put a 5mm thickness on your "lateral supports"
- put 10mm on the base thickness
- put 1,5mm of shell thickness
- put 25% infill.
- add 5mm chamfers in all corners

I think there's 95% chance it will work. You want it slimmer & sexier : make iterations, ask with a clear specification or pay for a design. With the new surface 4 out the door, I'm pretty sure people will make stuff. I for one know I'll have to prepare something for my wife. Tell you in 2 months.

As for aluminium : good point but at this time, given your design, better get it machined than 3D printed. Also the cost compared to nylon won't be competitive, and compared to a plastic part that can be honeycombed, it will be heavier.