[Build Log] Jetstream - Powermac G5 Case Mod [WIP]

[MEC-777]

9 minutes ago, Heesleemer said:

aw

 

Although intake fans and a slow exaust with passive air cooling may work due to who well air coolingworks on the g5 case

Well, the emphasis for the design of this build is around optimal air flow, low temps and silence. I have a very good idea now as to how the internal component layout will be. Passive cooling might end up being a part of it in the end. The GPU is already partially passive - it's fans don't even come on until it hits about 55*C.  

[mr.squishy]

YES I WAS WAITING FOR THIS BUILD LOG I AM SO HYPED

[MEC-777]

The more thought I put into this build, the more ambitious it becomes, lol. Have some "out there" ideas - all which will be revealed in time...

 

This update is more related to my thoughts on case fan designs and air flow dynamics more than anything else. This post is probably going to get very technical, so be warned.  Will also be doing a mini review of the Deepcool UF140 case fan. (This will also serve to indicate why the name "Jetsream" is quite appropriate for this project.  ).

 

Been toying around with various layout options in CAD drawings over the last while - trying to establish a final layout design. During this process, I've been fighting with trying to decide what size fans to go with for the intake. Will be going for an equal or slightly positive pressure on the air flow. There will be 3x 120mm exhaust fans, which means I need at least 3x 120mm or 3x 140mm intake fans to match/exceed the exhaust flow rate. Problem with 3x 140mm fans is the space they take up and the space that's available to work with. With cable management in mind, I'll have to really think out side the box to make 3 140's work. 

 

Bought a Deepcool UF140 fan last night for testing purposes, and because I'm considering using these in this build. Deepcool fans are the "poor-man's Noctuas" IMO. To clarify; I'm not talking about their cheap, clear-plastic LED basic case fans. I'm talking about their more premium branded fans - their UF, GF and TF series. I'm currently using 2 GF120's and a single TF120 in my current rig and have been very much impressed with their performance and silence. They definitely rival Noctuas in nearly every way - especially in cost.

 

Let's take a closer look at the UF140 for a moment. In the box you get:  

-the fan with high-quality black-sleeved black-wired 4 pin PWM connector

-12v and 7v molex adapters

-rubber fan mounts

-user manual/spec sheet

 

Contents are packaged very nicely and considering the price ($12) this is very good value. 

 

 

 

 

 

Just a brief description; the blue material is a harder plastic and the light grey is a rubberized coating/material, intended to reduce vibration when mounted to the chassis. A nice touch - it has a very premium, high-quality feel to it. At speeds below 80% the fan is essentially inaudible. At 12v it still remains extremely quiet with very good air flow. I don't have any tools or equipment to measure air flow rate, but based on it's listed specs, it is competitive with other much more expensive units. 

 

As for the colour, well I haven't yet decided on a colour theme for the build yet, so they may or may not match. But they look better than the Noctua brown/beige, IMO.  

 

 

Case Fan Technical Analysis, Part 1 (of 2):

 

Now, here's where things are about to get very technical. Probably WAY more technical than most people would bother to get when talking about case fans. To be clear; for most people, a fan is a fan and technically, all do their job in moving air sufficiently through a case and most work just fine as is. But this is where my mentality strays. For me, "sufficient" means; there is room for improvement.   

 

With a mechanical engineering background and OCD - I analyze and scrutinize the design of just about everything I see. If I see something that "could be better", it bothers me. In some cases, I take it upon myself to redesign it as I would see it better optimized. Well, I'm not about to redesign my own case fans, but there is something I plan on doing about the inerrant major flaws I've observed in most case fan designs. 

 

To start off on the technical analysis; I'd like to start off on why I like Deepcool's fan designs over others and why I'm sticking with them primarily for this build (aside from the difference in cost). It stems from my love of airplanes and more specifically; jet engines. If you look at the engines on a commercial jet, they actually produce their high thrust by large ducted fans driven by a turbine engine, not by the exhausted burning fuel like in a fighter jet engine. They are "high by-pass" turbo-fan engines. High by-pass meaning; most of the air being pushed by the large main front fan (the one you see in the front of the engine) by-passes the engine itself and is blown back at high velocity through a "duct" producing the "thrust". 

 

Like this diagram:

 

But why am I talking about ducted fans and jet engines? Because ducted fans are much more efficient at producing thrust (moving air) vs an "open" propeller. A ducted fan (which is what all case fans are, essentially) is a propeller with a housing or shroud around the blades, aka an "impeller".

 

Why is a ducted fan better than an open fan/propeller? Well simply put; with an open propeller, air is allowed to move out and around the tips of the blades. This created turbulence and reduces the efficiency. Ideally, you want a propeller to move air in one direction and it doesn't do any good if a portion of the air is being thrown outwards instead. So by placing a fan inside a duct or shroud, you essentially are forcing the air to move (more or less) one direction as the air can no longer go out and around the tips of the blades. Also, air has mass and thus; it has inertia when in motion. So a column of air moving through a duct will (more or less) tend to keep on moving the same direction, once the flow is in motion. The closer the duct/shroud is to the tips of the fan blades, the less "leakage" or cavitation you will have, the more effective the fan will be. This point leads me to why I like these Deepcool fans. Let's take another closer look at the UF140 and compare it to a Fractal R3 140 fan. 

 

Both have the same number of fan blades, but that's where the similarities end.

-The blades on the Deepcool have bit larger surface area and have a more aggressive pitch near the inner hub. (if you want to know why that matters, let me know).

-The gap/space between the blades and the duct/shroud is much more open on the Fractal. 

-The duct/shroud on the Deepcool is much more cylindrical, and tighter to the fan blades. 

 

 

 

 

You can see here the chamfered edges on the intake side of the Fractal fan and how much of a gap there is between the shroud and the blades. With some brands this design is marketed as a way of improving how much air can be effectively "sucked in" to the fan. In reality, it really doesn't help the fan take in more air. A fan will not suck air in from the sides like that. All it does is allow more air to leak or cavitate past the tips of the blades. In fact, it probably blows air out through those chamfers (with a smoke test, you'd be able to see it). In terms of being optimized for flow, this Fractal fan is of very poor design, IMO. It's is one of their "cheap" fans and it gets the job done, don't get me wrong. But it could be better and that's mainly what I'm looking at here. With the Fractal fan, a lot of air can leak/blow out the sides, past the blades instead of being force through. By contrast, the Deepcool fan should is cylindrical and uniform, following tight to the fan blades from top to bottom, so very little leakage past the blade tips can occur. Any air entering this fan is going through and coming out the other side. It has no other option but to pass through.  

 

That's it for part 1. Part 2 will come later this afternoon/today and will talk about the main problem with nearly all case fans (including Deepcool's) and what can be done to correct it.  

 

[Heesleemer]

Nice read, I was going to pick up some noctuas for future mods, but looks like I'll go DeepCool. Blue/grey would go so well with the G5 case. 

[MEC-777]

Case Fan Technical Analysis, Part 2:

 

The main problem with nearly all case fans is the fact that they do not blow air straight back in a nice, uniform flow. Instead, they actually "spray" a lot of the air outwards. I say "nearly all" because there are 1 or 2 fans out there designed to redirect the "spray" into a more uniform column of air, but more on that a little later. You see, the fan blades don't just push air straight out the back, they also push air outwards from the center (which is why I talked about how the design of the shroud is important in preventing air from leaking out and around the ends of the blades in part 1). While the air is still within the confines of the frame/shroud of the fan, all is fine and dandy - the air can't escape, but only be pushed by the fan. However, once that air leaves the shroud, all hell breaks loose. Not only does a significant portion of the air exiting the fan do so on a sharp outward angle, but it's also swirling from the spinning blades. When moving air hits stagnant (non-moving) air it creates even more turbulence. So we basically have a torrent of swirling air that is being flung outwards from the fan, only some of which is being blown "back" directly in the path behind the fan. There is also a "dead zone" directly behind the motor hub of the fan where no air is moving at all. 

 

Now, for the simple purpose of pulling fresh air inside a case and exhausting hot air out, again, nearly any fan does this just fine. I'm not disputing that at all and for most folks, this should be more than adequate. 

 

So why does this still bother me and why am I going into such depth when these fans are still technically "doing their job"? Why does it matter? Well, there are several reasons, in my view: 

-If you have a side panel window, they tend to get sprayed with dust by the front fans (even if you have dust filters - I have evidence...).

-If you want/need air flow to be directed at specific system component(s) that happen to be a fair distance from the fan(s) without the need to have the fan(s) screaming at high speed. 

 

To visualize the "spray" phenomenon I'm talking about, here's a video of a smoke machine test performed by Silverstone for promoting their special "air penetrator" fans (more on those in a moment). 

 

Also, take a look at the dust collection on the inside of the window on my S340 and notice the higher concentration close to the front, showing the amount of air being sprayed outwards instead of being directed at the system components further away. 

 

 

(This is also proof that dust filters don't filter everything,  This is about 1 month of accumulated dust, but keep in mind I have 4 small dogs).

 

As you can see from the smoke test demonstration, if you look about 6 inches above the fan, right where you would expect the air to be blowing, there is almost no flow there. It's all mostly being blown out to the sides. 

 

So what can be done about this? How can the air flow be directed straight back in a column where it would be more effective? Well Silverstone has one solution with their air penetrator fans. The way they achieve this is by using curved opening or "slots" if you will, that counter-acts the direction of the flow and re-directs it straight back with a stator-like effect. A "stator" is a set of stationary fins or blades that reside right behind the blades on a turbine to help direct the air in the desired direction. The Noctua NF-F12's use stator blades incorporated into the motor hub supports.

 

Silverstone air penetrators:

 

Noctua NF-F12 with stators:

 

Even though both these fans incorporate designs to help direct the air flow and make the fans more effective, they both still have their own set of down-falls:

-The Silverstones, as a result of all the slots, have significantly reduced flow rate (CFM) and reduced static pressure. 

-The Noctua is still prone to the outward spraying effect. 

 

So, is there a way to reduce or even eliminate the "spray" effect, improve the fan's effectiveness by redirecting the air and yet not reduce the flow rate or static pressure? I believe there is and I have an idea in-mind of exactly how to achieve this. But that reveal will have to wait for another time.  

 

[MEC-777]

1 hour ago, Heesleemer said:

Nice read, I was going to pick up some noctuas for future mods, but looks like I'll go DeepCool. Blue/grey would go so well with the G5 case. 

Don't get me wrong, Noctuas are really good fans, among the best, IMO. They're just really expensive and the performance they deliver isn't necessarily that much better than some other brands that cost half as much. Not enough to justify the price premium, IMO anyways. They certainly have put in more R&D than most fan makers, I'll give them that much.  

 

 

[Heesleemer]

23 minutes ago, MEC-777 said:

Don't get me wrong, Noctuas are really good fans, among the best, IMO. They're just really expensive and the performance they deliver isn't necessarily that much better than some other brands that cost half as much. Not enough to justify the price premium, IMO anyways. They certainly have put in more R&D than most fan makers, I'll give them that much.  

 

 

yeah, honestly I keep going back to them for their customer service, I will pay a bit more (like 5 more than other premium fans) for the service. Same thing applies in other parts of life too... even as a broke grad student. 

with that said if those fans are as good as you say.... for a secondary project i dont see a reason to go all out

[MEC-777]

Ok, well moving on from my over-the-top case fan technical analysis rambling that most people probably don't care about, lol, time for a real update.  

 

Had a good long look at the case today to try and nail down the next steps. Decided to further strip down the frame by removing the back panel and "handles" (which is all one piece), to expose the core of the frame which would make it a lot easier to work on. 

 

Had to customize one of my screwdrivers so it would be short enough to remove the 5000 screes holding it together.

 

 

Now that the main frame and outer shell are separated, will make it much easier to clean, prep, cut, drill - what ever needs to be done. 

 

 

 

Spent a lot of time just sitting staring at this, visualizing all the components and what all would need to be done. 

 

Would love to use these 140's in the final build. These will move lots of air at lower rpm which will keep it super silent. Might end up using a grand total of 7 of these bad boys. Depends on how thing come along with the design. I probably won't mount or cut any holes for any of the fans until after most of the components are positioned.

 

 

I was curious to see the inside of the PSU that came in the G5 - instant regret. So nasty!  lol

 

Again, after much racking of my brain and just staring at the darn thing for longer than I'd care to admit, I finally came to a decision on what to do with the front and rear panels. The thing is; I want the front and rear to look nearly identical and as of now, they are completely different. The front has the opening for the ODD drive bay, power button and a few little I/O features. The rear has 2 holes for 92mm fans, a ton of other I/O features and 4 expansion slot openings, as well as the lever to release the side panel (which I intend to retain and use). The solution I came up with is to cut out most of the front and rear perforated panels and install wood panels in place. 

 

These wouldn't just be any old pieces of wood, I'm thinking some really nice 1/4" solid wood panels which will be nicely finished. Haven't decided on a colour theme yet, though I do have some options in-mind. As per the inspiration for this build, I'm thinking something along the lines of a luxury private jet interior type concept... Not sure, still mulling all that over. 

 

Anyways, I got the front and rear panels taped off and marked for cutting. Weather turned chilly again today with a decent blanket of snow coming down.  So won't be doing any cutting until it get's a little warmer again. But, it's ready to be chopped and I'll be sourcing the wood panels hopefully this week, if I have time.  

 

 

Have to cut the rear panel out a little differently than the front so as to retain that side panel release lever. Made a little note as a reminder to NOT cut off the pin for that lever.  So, it'll be a little narrower, but it will look the same as the front, otherwise. 

 

 

Planning something special for the rear panel. Not quite sure how it's going to "work" yet, but will be hopefully sourcing out the parts for that as well while I source the wood this week. If you haven't guessed yet, I am planning to mount the motherboard in a rotated position so the graphics card is vertical. Silverstone has this layout in some of their cases, but I'm going to be putting my own spin on it.  

 

More updates coming soon...  

 

 

 

[mr.squishy]

Looking great! I think pretty much any wood would look good (say that 5 times fast), but I'm particularly fond of Maple and Mahogany. Keep up the awesome updates!

[MEC-777]

7 hours ago, mr.squishy said:

Looking great! I think pretty much any wood would look good (say that 5 times fast), but I'm particularly fond of Maple and Mahogany. Keep up the awesome updates!

Thanks.  

 

Yeah, I love the look of dark red mahogany. The perforated front and rear panels look kind of ugly to me as they are - especially in the silver colour. So I'm thinking to do the core of the frame in a gloss black to hide all the holes as much as possible.

 

Usually I have a pretty good idea of what the finished product will be/look like before I even start, but this one is causing me to second-guess everything and keep changing my mind, lol. Little frustrating, but I'm not making a single cut until I'm sure.

[mr.squishy]

2 hours ago, MEC-777 said:

Thanks.  

 

Yeah, I love the look of dark red mahogany. The perforated front and rear panels look kind of ugly to me as they are - especially in the silver colour. So I'm thinking to do the core of the frame in a gloss black to hide all the holes as much as possible.

 

Usually I have a pretty good idea of what the finished product will be/look like before I even start, but this one is causing me to second-guess everything and keep changing my mind, lol. Little frustrating, but I'm not making a single cut until I'm sure.

That's good, make sure you have full understanding of what you want to do before you do any work. It reminds me of a well known quote: "measure twice, cut once." It's hard to do, but remembering to always do that will prevent mistakes. I know an 80 year old carpenter that always follows this rule, and his work is amazing, even at his old age.

[MEC-777]

Working on a 3D rendering using AutoCAD 2014. AutoCAD is definitely better for pure 2D drawings and building layouts, which is mainly what we use it for where I work. For creating 3D drawings it's very unintuitive compared to other 3D modeling programs I've used in the past. But it's all I have access to (for now) and it will do the job just fine.  

 

I believe I have come up with a final internal layout that will allow to use 7 of these 140mm fans (5 intake and 2 exhaust). The CAD rendering will allow me to see exactly if everything will fit as I see it in my mind. Might end up 3D printing some custom parts as well. We have a 3D printer in the facility next door that could make some things for me. 

 

Anyways, here's the drawing thus far. It's just the shell of the core of the frame, power supply and one of the 140mm fans so far. 

 

[MEC-777]

AutoCAD rendering is coming along nicely. Just installed Autodesk Inventor 2016 Pro on my rig at home now, so I'll be importing this drawing into Inventor - a program that is actually meant for 3D designing.  

 

The progress: (can see some hints of the potential final layout). 

[nmil]

On 08/04/2016 at 6:13 AM, MEC-777 said:

AutoCAD rendering is coming along nicely. Just installed Autodesk Inventor 2016 Pro on my rig at how now, so I'll be importing this drawing into Inventor - a program that is actually meant for 3D designing.  

 

The progress: (can see some hints of the potential final layout). 

 

Glad to see you moving to Inventor. That will really speed up your work flow. If you ever need tutorials for Inventor, I would recommend TFI cad tips on youtube, his videos are really in depth and I have learnt so much from him. Also maybe checkout the Inventor 2017 beta, its 3d sketching much better than that of inventor 2016 or 2015. 3D sketching is really useful for wiring runs or tubing runs.

[Heesleemer]

any update on this? 

[MEC-777]

2 hours ago, Heesleemer said:

any update on this? 

It's going to be a while before I can get back on this project, unfortunately. Been super busy with a lot of things going on right now. I will definitely update once it's back in full swing though.  

 

I need to work more on the design and CAD rendering first anyways.