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Completed STX160.0 - The most powerful ATX unit, in the world!
- Thread starter jeshikat
- Start date
This looks promising though a bit pricey: https://www.amazon.com/dp/B00XPBFQ0U/?tag=theminutiae-20
I suspect it's one of those things: cheap, small, powerful, reliable. Pick 3.
There are others that are cheap, relatively small, and powerful enough, but they lack detailed specs of important things like ripple and operating temperature.
I suspect it's one of those things: cheap, small, powerful, reliable. Pick 3.
There are others that are cheap, relatively small, and powerful enough, but they lack detailed specs of important things like ripple and operating temperature.
So this thread is amazing/borderline epic.
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Also, now we know how far you will go to prove a point. This is like, Count of Monte Cristo level deep.
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Also, now we know how far you will go to prove a point. This is like, Count of Monte Cristo level deep.
Doesn't have to actually be kept outside the case, I was just thinking along the lines of splitting up the AC power and having it go to seperate 12V and 19V converters rather than trying to convert one voltage to the other.
Gotcha. I forgot about it last night but I realized I need a 5V source too for the M.2 adapter. So that'd mean a 12V brick plus 3 buck/boost converters, and at that point the HDPLEX doesn't seem like such a bad idea if I could get it to work
I contacted Larry at HDPLEX and he's checking with the engineer so maybe they have a solution but in the meantime I'm considering the Pico Box Z4-200-ATX.
I contacted Larry at HDPLEX and he's checking with the engineer so maybe they have a solution but in the meantime I'm considering the Pico Box Z4-200-ATX.
Gotcha. I forgot about it last night but I realized I need a 5V source too for the M.2 adapter. So that'd mean a 12V brick plus 3 buck/boost converters, and at that point the HDPLEX doesn't seem like such a bad idea if I could get it to work
I contacted Larry at HDPLEX and he's checking with the engineer so maybe they have a solution but in the meantime I'm considering the Pico Box Z4-200-ATX.
What do you need 5V for? For PCIe only 12V and 3.3V supplies need to be present. And I wonder the if you need to supply your own 3.3V considering the M.2 slot is PCIe based and might be able to source enough current for the 3.3V, The GTX1060 FE doesn't even draw 3.3V at all.
http://www.pcper.com/image/view/72154?return=node/65820
That's possible too.
The Bplus P4SM2 M.2 adapter takes 5V and converts it to 3.3V onboard. And that's interesting, the EVGA 1060 uses a reference PCB so maybe I could get away without it for this card at least.
It was supposed to be last update, but for real this time, this is the last post on threads/PEMSERTs!
Designing the case part 7: Bend reliefs and flat patterns
So like I mentioned last time, one trick for getting a PEMSERT (or other feature) close to bends is to just not bend the sheet around the fastener. What do I mean by that?
Hello, you've reached the retention department
The retaining screw for the expansion slots often requires this so I'll use it to demonstrate.
The problem is that the hole in the video card's bracket for the retaining screw ends up right up against the bend line when that flange is formed from the frame:
There are a few clever solutions to get around this problem, like using a separate piece that's attached to the frame with screws or welding, instead of doing a bent flange. I'd caution against getting too clever with how the expansion cards are attached though because the HG Osmi tried and their method works, but only with certain cards. Users have had to resort to bending or filing the frame to get their own cards to fit.
So the workaround is to just not bend the sheet near the fastener, like so:
The idea is to make some cuts in the sheet such that when the flange is formed, this protrusion remains in the gap in the bend, giving a nice little flat space for the nut.
Bend reliefs
How much you'll need to worry about this will depend on the manufacturer. Some will insert all the bend reliefs for you while others will make exactly what you ask them to, mistakes and all.
It's good practice to take this into consideration from the beginning even if the manufacturer is willing to do it though. That said, it is much easier when working with a CAD program that has sheet metal tools because modeling it manually is a pain.
So what are bend reliefs? You may have noticed in the above image that there's quite a gap above and below the tab, those are bend reliefs:
I've removed the reliefs in the image on the right, it looks cleaner and more efficient so why not do this?
The thing is though is that the CAD model is showing the final, post-formed state of the sheet metal. But it starts life as a flat sheet which is then later bent to form 3D shapes, typically by a press brake like I talked about in Part 2. The bend reliefs ensure that the sheet doesn't tear at the transition point between where it's supposed to bend and where it's supposed to stay flat.
I went with conservatively large bend relief for the nut 'cause why not but it's possible to go with narrower reliefs:
The main limitation on how wide/narrow to make the bend relief is the width of the cut (kerf) for the process used to cut the sheets. A laser has a much narrow kerf than a router bit for example. Half the material thickness would be a good starting point though.
Flat patterns
Speaking of the cutout for the expansion slot flange, time for a pop quiz! Quick! What is wrong with the following image?
Ding ding! Time's up, hand in your answers.
The answer is that the cutout isn't big enough for the flange that is to be formed. The easiest way to demonstrate this is to show the flat pattern for the above hypothetical design:
In this flattened state it's obvious why it won't work. I can't use the same section of metal for both the flange and the area of the frame above the cutout at the same time, it's one or the other. Let me fix it real quick:
So I've made the cutout taller, now back to the flat pattern to check:
This is an important thing to keep in mind when forming flanges in the middle of the part. The corresponding cutout it's formed from has to be big enough.
And as you've probably figured out by now, flat patterns are the "unfolded" 2D version of the sheet metal part. This process is usually done automatically by the CAD software if it has a sheet metal package but it can be done by hand. This involves knowing or estimating the K-factor for the material and working through the formula for the bend allowance though.
If your CAD software can't do flat patterns and you're lazy, it's usually possible to eyeball it. Just be conservative on the cutout size to make sure you don't have interference issues like I showed.
So just a short update today. Not sure what the next update will be yet, I'm thinking bend order and press brake tooling width but we'll see.
Table of Contents
Next Update
Designing the case part 7: Bend reliefs and flat patterns
So like I mentioned last time, one trick for getting a PEMSERT (or other feature) close to bends is to just not bend the sheet around the fastener. What do I mean by that?
---------------------------
Hello, you've reached the retention department
The retaining screw for the expansion slots often requires this so I'll use it to demonstrate.
The problem is that the hole in the video card's bracket for the retaining screw ends up right up against the bend line when that flange is formed from the frame:
There are a few clever solutions to get around this problem, like using a separate piece that's attached to the frame with screws or welding, instead of doing a bent flange. I'd caution against getting too clever with how the expansion cards are attached though because the HG Osmi tried and their method works, but only with certain cards. Users have had to resort to bending or filing the frame to get their own cards to fit.
So the workaround is to just not bend the sheet near the fastener, like so:
The idea is to make some cuts in the sheet such that when the flange is formed, this protrusion remains in the gap in the bend, giving a nice little flat space for the nut.
---------------------------
Bend reliefs
How much you'll need to worry about this will depend on the manufacturer. Some will insert all the bend reliefs for you while others will make exactly what you ask them to, mistakes and all.
It's good practice to take this into consideration from the beginning even if the manufacturer is willing to do it though. That said, it is much easier when working with a CAD program that has sheet metal tools because modeling it manually is a pain.
So what are bend reliefs? You may have noticed in the above image that there's quite a gap above and below the tab, those are bend reliefs:
I've removed the reliefs in the image on the right, it looks cleaner and more efficient so why not do this?
The thing is though is that the CAD model is showing the final, post-formed state of the sheet metal. But it starts life as a flat sheet which is then later bent to form 3D shapes, typically by a press brake like I talked about in Part 2. The bend reliefs ensure that the sheet doesn't tear at the transition point between where it's supposed to bend and where it's supposed to stay flat.
I went with conservatively large bend relief for the nut 'cause why not but it's possible to go with narrower reliefs:
The main limitation on how wide/narrow to make the bend relief is the width of the cut (kerf) for the process used to cut the sheets. A laser has a much narrow kerf than a router bit for example. Half the material thickness would be a good starting point though.
---------------------------
Flat patterns
Speaking of the cutout for the expansion slot flange, time for a pop quiz! Quick! What is wrong with the following image?
Ding ding! Time's up, hand in your answers.
The answer is that the cutout isn't big enough for the flange that is to be formed. The easiest way to demonstrate this is to show the flat pattern for the above hypothetical design:
In this flattened state it's obvious why it won't work. I can't use the same section of metal for both the flange and the area of the frame above the cutout at the same time, it's one or the other. Let me fix it real quick:
So I've made the cutout taller, now back to the flat pattern to check:
All good now!
This is an important thing to keep in mind when forming flanges in the middle of the part. The corresponding cutout it's formed from has to be big enough.
And as you've probably figured out by now, flat patterns are the "unfolded" 2D version of the sheet metal part. This process is usually done automatically by the CAD software if it has a sheet metal package but it can be done by hand. This involves knowing or estimating the K-factor for the material and working through the formula for the bend allowance though.
If your CAD software can't do flat patterns and you're lazy, it's usually possible to eyeball it. Just be conservative on the cutout size to make sure you don't have interference issues like I showed.
---------------------------
So just a short update today. Not sure what the next update will be yet, I'm thinking bend order and press brake tooling width but we'll see.
Table of Contents
Next Update
Last edited:
Ah yes, I forgot to give credit to @slipperyskip for some of the inspiration for this, thanks for reminding me!
Wow, how far the PC industry has come in the last 13 years. Today, that build would have RGB LED strips to light the disco ball!
@Aibohphobia , forgive me for my noob skepticism, but how does one actually (in real life) bend the retention tab the opposite direction from the bends that form the edges of the enclosure (and in the "middle" of the sheet at that)? Is this bend performed prior to the edge bends?
That's what I'll talk about in the next update. But basically to make bends in the other direction you just flip the part over:
About 30 seconds in, the operator does that in the above video.
Whether a bend like the retention flange is done before or after the other bends depends on the geometry of the parts.
About 30 seconds in, the operator does that in the above video.
Whether a bend like the retention flange is done before or after the other bends depends on the geometry of the parts.
Does anyone know what would happen if you actually made a zero-depth (as opposed to zero-width) bend relief? I know the panel can deform a little in that area, but would it weaken or damage the sheet in any way?
What is the slot height from the bottom of the slot to the flange for the PCIe retention tab?
In making my own case I'm trying to figure out what the dimensions of full-height slots and I/O area, and the technical drawings I've found online don't include the retention tab. I'd like to get this right the first time since the tab on the case needs to fit exactly with the PCIe card's tab.
In making my own case I'm trying to figure out what the dimensions of full-height slots and I/O area, and the technical drawings I've found online don't include the retention tab. I'd like to get this right the first time since the tab on the case needs to fit exactly with the PCIe card's tab.
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