3D Printed Mod Corners - For 2D Panel Construction

[Thehack]

Yes, very much. Admittedly, I don't know much about ISO standards for self-tapping screws, but you can get M3 screws and nuts everywhere in the world, no problem. Just provide people with the exact ISO number for the nuts, because there are different types of those.



I think with hexagonal inserts you also get a good bit of tolerance, because the nut can move around. Also, because holes in SLS prints aren't the same dimensions depending on which orientation you print them in, the screws might require differing amounts of force to screw in.



Jup, both of those. There are a lot of different types of heads available, standard and non standard. Even stuff like knurled thumb screws are available in a multitude of different materials, finishes and lengths. That alone is a dead-set argument for M3.

The one point for self-tappers is cost. Because these pieces are 3D-printed anyway, making a separate version for those wouldn't cost you anything either.

How are you going to handle different panel thicknesses?

It's open source for anyone to iterate but I intend on making a 5mm size as well. Those are the two most common sizes.

Going to a nut design I'd have to increase the distance of the screws from the corner. This means the corner takes up more space which increases the overall volume of the case.

The fit and finish of my SLS printed parts work very well with the self tapping screws regardless of the orientation.

 

[iFreilicht]

Going to a nut design I'd have to increase the distance of the screws from the corner. This means the corner takes up more space which increases the overall volume of the case.

The corner will be larger, but I don't agree that it will necessarily make the case larger as well.

How are you solving the critical area next to the mainboards I/O shield? It seems like a corner piece of any size would lose valuable space to the right of the motherboard.

 

[Biowarejak]

Perhaps that could be solved with standoffs or fan-height clearance above the motherboard?

 

[iFreilicht]

Ah right, you could use longer standoffs to place an HDD below the mainboard, then the corner could snug in under there as well. Good thinking!

 

[ElinaNguyen]

Can you upload the Sketchup file? I can print out these corner and give some feedback to you.

 

[Thehack]

Can you upload the Sketchup file? I can print out these corner and give some feedback to you.

Here you go. Google Drive Download

The corner will be larger, but I don't agree that it will necessarily make the case larger as well.

How are you solving the critical area next to the mainboards I/O shield? It seems like a corner piece of any size would lose valuable space to the right of the motherboard.

Ah right, you could use longer standoffs to place an HDD below the mainboard, then the corner could snug in under there as well. Good thinking!

A larger corner piece will increase the size of the case near the IO as you've noticed. The answer would be to keep the motherboard low, but extend the width of the case and use the extra space for storage options or cooling.

----

I intend to make one "standard version" to see where this idea takes off. So far, checking the specs for M3 nuts, I don't think M3 is feasible if we are using nuts, it would have to be M2.

So this is where it diverges.

M2 - Nut inserts (with tabs to hold into place)
+ More styles to chose from
+ Easy to source from local shops
+ Low profile
+ No need to tap
- Tiny nuts are annoying to handle
- Lower tolerance due to tight spacing

M3 - Self Tapping
+ Easy to use, high tolerance
+ Easy to assemble
+ One source solution
- Limited choices in screw style
- Higher profile (pro if you like the industrial look like i do )
- Possible to have a slightly mis-aligned tap if you aren't careful.

It seems like everyone is hungry for a sandwich style build so I'll close the poll. There will be a new poll, whenever the old one closes, then I think I can make a new one...

Which one would you rather see?

M2

----
M3

 

[iFreilicht]

M3

Those are not M3 screws.

 

[Thehack]

Those are not M3 screws.

They are self-tapping M3 screws, which is what I have used. The design will use either self-tapping M3 screws, or M2 machine screws + nut.

 

[Biowarejak]

I'd like to see the M2 plus nut, personally.

 

[iFreilicht]

They are self-tapping M3 screws

I'm pretty sure that is not the case. M3 is pretty much universally short form for "ISO metric machine screw with 3mm nominal diameter". By definition, a self-tapping screw is not part of this group.

EDIT: Not true, see below.

I'd like to see the M2 plus nut, personally.

Jup, I think that's the better option.

 

[Thehack]

I'm pretty sure that is not the case. M3 is pretty much universally short form for "ISO metric machine screw with 3mm nominal diameter". By definition, a self-tapping screw is not part of this group.



Jup, I think that's the better option.

Yes. It usually means ISO metric machine screw, but I wanted metric measurements and in self-tapping. I was able to search for a self-tapping screw that uses metric measurements by buying "M3 Self-Tapping Screws." Whether or not that is legitimate remains to be seen .

 

[Biowarejak]

Ah. Well, if you plan on continuing to develop it into a potential product, I do hope you find a way to make that less confusing to the end consumer.

To be fair though, M3 means "Metric - 3mm diameter" so I'm sure there are self tapping options for people that would need it.

 

[iFreilicht]

Ah, that's kinda what I was expecting. Actually, I have to correct myself as well, M3 is just the denomination for the thread, so it should really read: "ISO metric machine screw thread with 3mm nominal diameter".

And actually, after digging a little bit, it seems there are no self-tapping screws standardised by ISO, but there is the DIN 7500C which describes self-tapping machine screws for threads M2, M2.5, M3 and up. I should fact-check better.

EDIT: @Biowarejak ninja'd me

 

[Biowarejak]

Haha happy to help

 

[Biowarejak]

You could probably source some self-tapping fan screws, now that I think about it. But the diameter tends to be a bit larger than I think you'd want.

 

[Thehack]

You could probably source some self-tapping fan screws, now that I think about it. But the diameter tends to be a bit larger than I think you'd want.

Yes. The fan screws are fairly large in comparison. I also prefer hex head or torx as they are resistant to stripping and they look much better.

 

[Biowarejak]

This is true.

-Edit-

However some people do like more of a flush look, I'm sure. The nice thing is how easily modified the component is to satisfy everyone's preference.

 

[wywywywy]

So I spent a bit of time on the original version this evening, and this is what I got.

This is how it looks in the slicer. I had to re-orient it.

And this is how it's sliced. I had to use brim because of the small bed contact surface.

This is how it looked fresh off the printer.

Spent some time cleaning the brim and support with a knife, and it looked like this.

This pic here I'm trying to show that the surface supported by the, err, support, is very coarse and not nice at all. But sorry for the blurry image I don't have a macro lens and it's really small.

I also printed a few small panels for test fitting. In hindsight I should have done them in a difference colour.

And this is how the corner fits. I don't have any 3mm self tapping screws so I used small wood screws (forgive me lord). The first thing you'll notice is that the screws are not screwed in... because they'll bump into each other! The max length is around 7mm, given 3mm panel thickness.

My conclusion is that as it is, it's suitable for SLS printing but not FDM. The "neck" seems a bit week. So for FDM, I think it'll need to be re-designed to get rid of the support, and also possibly 50-100% bigger.

I uploaded the STL to Shapeways, and the quotes are £2-3 each, with £9 shipping for 8 of these. Shipping is free this week.

More tomorrow.

 

[Biowarejak]

That's awesome!

 

[Thehack]

So I spent a bit of time on the original version this evening, and this is what I got.

This is how it looks in the slicer. I had to re-orient it.

And this is how it's sliced. I had to use brim because of the small bed contact surface.

This is how it looked fresh off the printer.

Spent some time cleaning the brim and support with a knife, and it looked like this.

This pic here I'm trying to show that the surface supported by the, err, support, is very coarse and not nice at all. But sorry for the blurry image I don't have a macro lens and it's really small.

I also printed a few small panels for test fitting. In hindsight I should have done them in a difference colour.

And this is how the corner fits. I don't have any 3mm self tapping screws so I used small wood screws (forgive me lord). The first thing you'll notice is that the screws are not screwed in... because they'll bump into each other! The max length is around 7mm, given 3mm panel thickness.

My conclusion is that as it is, it's suitable for SLS printing but not FDM. The "neck" seems a bit week. So for FDM, I think it'll need to be re-designed to get rid of the support, and also possibly 50-100% bigger.

I uploaded the STL to Shapeways, and the quotes are £2-3 each, with £9 shipping for 8 of these. Shipping is free this week.

More tomorrow.

Hey I really appreciate your help with the prints.

The original design is meant to be used with 8mm screws which will not interfere with each other.

The neck is cosmetic. Can you try to break it to see how it holds up? If it is not strong enough I will increase it's size a bit.

Finally they are meant to be printed in an array so the final print cost should be around 10 Euros or USD for 8 pieces not including shipping.