How To Build Your Own SFF case

8/14/2019 How To Build Your Own SFF case

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How to Build Your Own SFF caseby Alex Watson

We turned to master modder Syrillian for a series of articles showing how to build yourself a perfect small formfactor case

One of the most obvious trends in PC technology is the increasing popularity of laptops - but while many people

can see the attraction of a small PC, it's very hard to build your own laptop and you'll often be stuck withcomponents that are significantly slower than their desktop relations.

A small form factor machine is a good compromise between size and speed, but finding the right case isn'teasy. Zalman's HD 160 XT Plus, for instance, is certainly ideal for a sleek looking media PC, but at £400 it's notexactly cheap.

That's why we turned to expert modder Daniel Costin (aka Syrillian) to write a series of articles showing how tobuild your own SFF case from acrylic. He seemed like the ideal man for the job, having constructed theamazing Gemini mod for our Towers of Power feature. The first post in his project modding log, 'Building withAcrylic: A SFF excursion' is up on the site now. In his first post, he looks at the tools necessary to do the job.

You can follow the mod log regularly by checking back at www.custompc.co.uk/blogs/syrillian, or by subscribing

to his blog's RSS feed. We'll update this article regularly with links to each post, too. If you need help andadvice following along, drop Daniel a line in the comments of his blog.

1. Introduction and Tools

Greetings fellow PC enthusiast, my name is Daniel, and I have been building custom PC cases for about 1-1/2years. I do this as a hobby, and I have had quite the learning journey along the way. Although there is muchmore to learn and experiment with, I would like to share some of what I have learned so far. I have no formal or technical background in the Trades, or in Art or Design. I have been a builder of “things” for as far back as I canremember. One area that I have dabbled in is carpentry and finish-work; this is where I get my background for the use of the tools that I will be using and discussing.

Building and modding for oneself is very rewarding, and I recommend that any that are so inclined give it a go.That being said, shall we begin?

This case-project will most likely be constructed entirely from bronze-coloured acrylic, but there may be a littlealuminium tossed in for good measure.

SafetyFirst and foremost – protect yourself. Eye protection and respiratory protection are what I would consider “mandatory”:

The tools you use do not need to be state-of-the art, or top-of-the line; however the cutting elements such asdrill bits and saw blades do need to be of the best quality available.

This is the main staple for me: The rotary tool. With a Dremel and the attachments shown in the image below(click for a bigger version) it is possible to construct an entire case. It is not the ideal tool, but it can be done

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with appealing results. Using a rotary tool for this type of project is akin to mowing the lawn with a weed-whacker.

The second tool is a circle-saw. I prefer cordless as I seem to become entangled in power cords if I use morethat one or two corded tools in the same session. Since the work in this project for the saw is relatively light(1/4” thick acrylic) there is no need for an AC-powered worm-drive. As you can see this saw has been throughthe ringer. As stated before appearances can be deceiving; this tool may not be much to look at, but it performsflawlessly with a new US$5.00 blade. Cuts straight and true – that is what matters.

Below, the indispensable cordless drill (Bit-types will be covered later):



To keep things true and right:

Angles are virtually a necessity if one wishes to avoid aggravation and frustration. These C-clamps are also anecessity for me:



For larger projects a table saw may be required:

This is a small portable saw, but does the job. Using a blade that has about 80 teeth will produce a nice andclean cut. This saw is used to rip cuts longer than 12”, and for material that is thicker than ¼”.

I use a router and a homemade router-table for some cuts, but mostly for profiling.

This tool is also quite optional, but introduces new techniques for finishing edges and profiling corners.Polishing and buffing are done with several tools depending upon how much space there is to work with.



That pretty much covers the power tools.There are a host of small hand-tools that I use, but I will introduce those as I move through this project.Thanks for looking, and if you have any questions, comments, corrections or opinions please feel free to postthem.

2. Measuring and cutting

“Thank you” to the individual that sorted out the image issue. Please bear with me as I am an old dog trying tolearn new tricks.

Safety is once again paramount. I forgot to mention in my last post that loose clothing, dangly jewellery, andlong hair can be quite dangerous. Dressing and coifing appropriately will see you through the day with all your digits, limbs and scalp still in place.

There are basically three types of cuts that apply to this build; rotary tool, circle saw, and router bit. These arelisted in the general order of cleanliness of the cut from roughest to smoothest. This may vary depending uponthe condition of the tools and the cutting implements, but all things being equal, a rotary tool cut is the roughest,and router bit cut is the smoothest.

Note that a table saw with a 10” (75-80 teeth) blade designed for cutting plastics will yield a cut comparable or exceeding the quality of a flush-rout cut. Also bear in mind that these blades can be rather costly; the last one Ipriced was about US$ 100.00

Before I move on it is notable to mention that there are two basic types of acrylic; “cast”, and “extruded”. Castacrylic will not suffer the “melting” syndrome that extruded acrylic seems to suffer from when exposed to thegentle ministrations of a power tool that cuts.

Here is an image depicting the cuts (from top to bottom: Dremel, Circle Saw, Router)

The rotary tool cut will require some sanding before it can be used for capillary bonding, and a considerableamount of sanding prior to polishing (capillary bonding and polishing will be covered later on in this Log). Both

the saw cut and the Router cut are ready for bonding, and need far less sanding for polishing prep-work.

One subtlety that can ruin a project is how out of square the panels are. “Square”, as in how close to 90-degress all applicable angles are. This project will be constructed with all angles at 90-degrees. For the mostpart angles that are off-square by 1/32” across a 12+ inch edge can be fudged to work and look okay. One

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Using an angle, level and tape measure to set up the guide:

Clamped down:

Ready to cut:

Always: Measure twice, cut once. When the guide or jig is clamped into place I always check all relevantmeasurements again prior to cutting.

As I cut the panels to size I mark them appropriately with what panel it is (front, back, top, bottom, etc., and theorientation (up, down, front, back, etc

http://custompc.co.uk/blogs/syrillian/files/2008/05/8-cutting.jpg



A rotary tool can also be used to cut straight lines; it will require the sideways bit.

You will also need the straight cut guide attachment.

The simplest way to guide the cut is with the edge of the panel that is being cut.

This attachment should also have its own markings for measurements which make it very handy to use.

The next instalment will cover profiling and cutting holes in the acrylic.

My apologies for the inconsistent image sizing and quality, I am still trying to work out the error that seems toexist somewhere between the chair and the keyboard.

3. Scoring, Snapping and Profiling Acrylic Panels.

As previously stated, there is more than one way to skin the proverbial cat when it comes to cutting acrylic.Another tried-and-true method is scoring and snapping. There are, however, 2 limitations that come to mind.

The first is the tolerable thickness that can be snapped. The second is the slight bevel that scoring can leavebehind.

It is true that one could score and snap a piece of ½” acrylic, but the effort is not a reasonable price to payunless one has no other option. As a general rule I do not score and snap acrylic that is thicker than 3/16”, andin complete truth I almost always use power tools as opposed to snapping.

The second issue is the small wedge that is created when scoring. The removal of material leaves a wedgeshape in the acrylic, and when the piece is snapped, there is the smallest of bevels left behind. This is not aproblem insofar as bonding, and if one is bull-nosing or rounding the edge then the point is moot.

In truth the only issue that I have found is one of aesthetics, and this only applies to clear acrylics as the slightbevel can be on the inside of a non-translucent panel. On clear panels, the offending edge can still be sanded

and polished to leave a clean visible edge.

In addition to scoring, an untreated edge can be cleaned up and profiled with a scraper. Again, I eschew thescraper and gravitate toward power tools for profiling, cleaning and sanding panel edges. This is not to



disparage the use of hand tools; it is merely a personal choice of what I am able to produce the best resultswith.

Here is an example of a scraper (3 profiles and a flat edge), and a scoring knife:

When scoring I try to use the most sturdy straightedge that I have. In this case it is a steel angle that hasproven itself to be quite the reliable tool over the years…. they just don’t make ‘em like this anymore.

^^ When cutting (right-handed) the acrylic that I will keep is on my left and protected by the straightedge, andthe refuse is on the right, Should I make a mistake and run off of the straightedge with the scorer (generally willonly happen on the first pass) doing so will ensure that the marring and the error is on the piece that is notbeing used in the project. Note that I am placing a slight amount of pressure on the angle, this is to keep it snug

against the edge of the panel; doing so will ensure a 90-degree angle once the snap is done.

It is prudent to consider the orientation of all tools and work to cover any eventuality that Moore’s Law will tossyour way. I don’t know about anyone else, but I need all the mojo on my side that I can get.



Here is the scored acrylic.

For the most part, scoring half-way through a panel will be more than enough of a start to get a clean break. Inthis instance I scored less than 1/4 of the way through the panel. Once the scoring is complete, place an object that is at least 1/2″ think under the panel (on the opposite side of the panel that is scored), and just off to the side of the score line. One can also use the edge of a table or other flat and sturdy surface. Hold the panel frimly in place and give it a bend, the acrylic should snap cleanly alongthe score line. In this instance I used the 1/2″ x 1″ acrylic guide for the router table.

This image shows the bevel that I spoke of earlier.



The snap is very clean. The only un-clean portion is the part that was scored. In the image above, In thisinstance the piece on the left would be the piece to use. The piece on the right could readily be ripped to aclean edge, and put in the bin for future projects that require smaller pieces.

Note: I have seen scoring tools that were beveled on only one side. Using a tool such as this will reduce,perhaps even eliminate the bevel altogether from the panel that is to be used in the project. Profiling:Here is a homemade router table.

Here is a shot of the profile edge that is aligned for the pieces that I will be profiling. This particular profile willyield a very subtle ogee-type profile; note that the there is about 1mm of vertical drop-off at the end of thecurve. This will produce a very slight ledge. Although not technically an ogee, I use the word as a point of reference for myself.



Profiling thin sheets can prove to be problematic with a router. The issue lies in the guide bearing, and theamount of round-over to be applied to the edge.

Below is a shot of the router bit aligned for a smooth round-over. I have marked the guide bearing contact patchwith a small arrow. This is to illustrate the problem with profiling thinner panels of acrylic.

The piece that I am profiling is ¼” thick, and I am using a 3/8″ round-over bit. As one can see the guide bearingis at its limit of contact. It is true that that router can be lowered to bring the guide bearing down, but that alsoreduces the amount of round over. There are smaller round-over bits that are compatible with rotary tools, butthese do not have guide bearings. Although there is a surface to guide the panel, it is imobile and does notalways do a great job.

I only have a couple of router bits, so I need to make do with what I have. One edge treatment that I like is thefull bull nose. The same issue that plagues thinner panels also applies here.

It is simple enough to rout one side, but when the piece is flipped over, the guide bearing no longer makescontact in the same manner as the first side. This leads to a slightly off-kilter bullnose, but when the piece ispolished the flaw is not noticeable except by the most discerning eye.



Here are a couple of shots of the eased edges on the panels for this project.



Once all the panels have been cut and profiled I make certain to mark each one with is position (Front, Back,etc.), the orientation (Up, Down), and which side is intended to be exposed. The next step is to cut all inside cuts for fans, the I/O panel, switches and LED’s where applicable; I will cover that next week. 4. Hardware and Cooling Fan Placement

Before we move on to polishing, we really should cut the rest of the holes. I don’t always do it in the “proper”order; sometimes I polish the work I have done before cutting more holes. I do it this way as I have limitedspace, and at times it is easier and more time-efficient. But, (imho) it is preferable to have all rough-work doneprior to starting finish-work

One of the key points in custom cases that are a boon; the intake and exhaust fans can be placed wherever thebuilder wants and needs. This is especially helpful when it comes to air-cooled cases as it minimizes theamount of fans required, and the direction of airflow is completely custom. Additionally the overall dimensions of the case are in the builder’s control; we are no longer at the mercy of static-configurations.

For this project I decided on a “Home Stereo-esque” (amplifier) look insofar as overall dimensions; low profile,wide and not too deep. For Video I will be using a HD2900XT, and I would like there to be a direct intake in frontof the cards cooling fan. Additionally, it is my intention is to put a single 120mm fan on the front that is alignedwith the CPU cooler. There will also be an exhaust on the rear, but the exhaust fan in question is still not

decided upon as I have a couple of options and I need to have more of the case done prior to making thatdecision. One last aspect of air-control to address is pressure. A positive pressure (more intake than exhaust)can lead to more dust settling inside the case; it is my habit to attempt to keep the pressure as balanced aspossible.

But first, I need to ensure that all the components will fit, and that I will have enough space inside that case tohandle the hardware. This step may seem silly as conventional wisdom dictates that this aspect has alreadybeen addressed during the planning and design stage, and it was. Never-the-less I always check fitment andfinish before going on to the next step because I am human; I forget things and make my fair share of errors.Since I had all the components on the table, I decided mark the holes for the fans, and the holes for themotherboard standoffs. Note that it is advisable to leave the protective covering on the acrylic in place until thelast possible moment.

Double-checking the hardware layout:

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The side intake fan is going to be a direct-feed to the HD2900, it will also provide cooling for theSouthbridge.

Measuring along the X-axis:

Measuring along the Y-axis



Verifying the elevation and clearance for the optical drive (the HDD will sit under, and perpendicular to theOptical Drive):

Since this is going to be a system with an air-cooled CPU, I wanted there to be a direct airflow from front-to-back.

This build will be utilizing a Zalman 9700 cooler. The design plan is to direct airflow through the case from thefront-side fan cooling the RAM, Northbridge and directly feeding the Zalman cooler.

I realize that that there will be turbulence in the case due to the perpendicular feed of the side-intake, but I alsoplan to use a controller to keep the side-intake fan at a reasonable cfm so that it will not wreak too much havoc.Measuring for the front-intake fan placement:



Once I have the areas measured, I mark the panels with the radii that I will be using. In this case the radius onboth panels will be 2.25”

Motherboard:

I have a template for an ATX/MATX motherboard that I made from an acrylic panel, but since I had themotherboard out I decided to use the board itself. My personal preference is to use the components themselveswhen possible. Some points to consider are that some components may interfere with the mounting of other components, or interfere with plug-in points on the mobo. In this case it is the intake for the fan. The fan will siton the inside of the case, the appropriate space needs to be left so that the motherboard header pins and any

other hardware that attaches along the left-side of the motherboard will not be blocked by the inward-protrudingfan.



And the holes marked for drilling:

This evening I will be working on cutting the fan holes, and measuring for the optical drive cut-out as well asdrilling the holes for the case feet and power switch.



5. Cutting and Finishing Fan Holes

Cutting holes in acrylic can be approached in a number of ways. The first is with hole-saw bits, the second iswith a rotary tool. A jigsaw could be used, but it is inherently difficult to cut a round hole with a flat-bladed tool.This becomes increasingly problematic as the diameter shrinks, or the blade becomes wider.

I use a rotary tool as it is what I have become accustomed to, and the radii are dynamic: I can cut holes from

¾” to 12” in diameter and any increment in-between. Also, the rotary tool takes up much less space and thecost is much lower than a set of quality hole-saw blades that are static insofar as the diameters that they cancut. This is not to bad-mouth hole-saws, had I the facilities and the funding I would most likely have taken thatroute.

When measuring the radius, ensure that the bit is on the inside of the measurement and that the center-point isbisected or the circle will not be to cut to the intended size. The radius for a 120mm can is 21/4″.

I drill the centre-hole, and then use the pre-set circle-cutting guide to mark the bit-hole. This may seemsomewhat low-brow…. and it is. Never-the-less I found this technique to be error-free 100% of the time whenworking without plans or drawings.

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Here is a closer shot of an acrylic bit and a standard bit (acrylic on the bottom). As you can see acrylic bits havea more acute point. This bit design alleviates chipping that can occur upon inital entry, and yields a cleaner exit-wound. I have used standard wood bits with relative success, but if given the option then I would take thespecialised bits - hands down.

When setting up to cut the hole it is a good idea to ensure that the rotary tool and the guide will be able to travel

full circle without being impeded. If one is careful it is quite easy to stop the cut, re-clamp the work, and thencontinue on with the cut; but, I prefer to make the cut in one single rotation. The red dot in the image representsthe location of the C-clamp. I eyeball the placement to ensure that the cut can be made in one single sweep,and not be obstructed by the clamps.

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Here you can see that the clamps will not interfere with guide as it rotates through its arc.

One potential pit-fall to be aware of is that the guide will become “sloppy” toward the end of the cut, at about thepoint depicted below. The centre point that has been the guide up to now has been rigid. As the circle iscompleted the centre is no longer held in place.

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This can be remedied by stopping and taping the circle that is being cut to the panel that it is being cut from.But, once again that means stopping and starting the cut multiple times; rather than do that I have chosenanother method.

When the cut is almost done I shift the focus of my guiding hand from the centre of the rotary tool guide to theend that is opposite from the tool itself. I start pulling the rotary tool in a decreasing radius manner.

This leaves a small barb in the panel, but it is easier to remove more material than it is to put it back should thebit jump and cut in to the portion of the panel that one is fabricating Barb: Please take care if you use your finder to run the inner edge to check for smoothness. Acrylic canbe razor sharp and will lay any flesh open at the slightest of provocations.

Since the inside of the cut will need to be sanded, I consider the barb to be “no big deal”, in reality it only takesabout 3-5 seconds to remove it with the rotary tool sanding drum

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Here you can see the rest of the rotary cut that was produced by the sideways bit. Not bad, but definitely needssome clean up.

To remove the barb I use the rotary tool at a medium setting and gently tap the barb to reduce it to the rest of the diameter. Then, I smooth the entire edge by running the sanding drum around the inner edge in a clockwisedirection. To keep the circle balanced, the sanding should be uniform all the way around.

When I am sanding the inner edge, any flaws become apparent as I can feel them as I move the rotary tool. Icontinue to carefully sand down the edge until it is smooth, and the circle is perfectly round. This process willincrease the diameter by about .5 mm - a negligible tolerance.

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Enso… (or at least as close as this monkey can get):

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Thus far I have profiled all edges, cut both 120mm fan holes, polished all edges, and have made the cut-out for the optical drive. Those processes will be in the next post.Thanks for taking a look.

7. Polishing

I needed to attend to 2 more cuts before I went to the polishing.

Lately when I have been building and modding I have been using slot-loading optical drives. I have but one left,and it is for my current personal project… selfishness is not gentlemanly, but it is core to the case design. Theslot-loading drives make for a very clean face (please excuse the “noisy” shots):

TJ07

Custom Case (Halcyon).


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But, for this project I have a tray-loading drive.

I still want to keep the face of the case as visually clean as possible, so I have removed the bezel on the trayitself so that the cut out can be made smaller. I’m not sure how I will finish the bare tray, but I will cross thatbridge when I get there.

In this instance I used a flush rout bit to cut out the rectangular hole for the optical drive tray.

This part can be tricky when making custom cases. The alignment (vertical and horizontal) needs to beessentially perfect so that the tray slides in and out freely and cleanly; allowing some leeway for error may be inorder. Note that the last portion of the previous statement really only applies if one is working without plans. If afull technical drawing or a CAD rendering (complete with dimensions and measurements) is done then this

portion of the build is not as difficult.

The Optical drive will sit on a platform or perhaps be mounted to acrylic panels in the traditional manner. Mostlikely it will be via the traditional manner as I can cut vertical slots in the panels so that I am able to adjustthe height that the optical drive sits at, and horizontal adjustment can be done with the panels (but that is later on).

I used the fence guide to make the appropriate cuts. I drilled the pilot hole then placed the panel to be cut onthe router bit. Then I squared up the panels using an angle. Once I had the all the parts lined up properly Iclamped the fence guide to the routers table top and proceeded to make the initial cut making sure to stop justwithin the line that I used to mark the perimeter of the cut.

The cut-out required was too tall to be made with 2 passes of the router, so I needed to make 2 very short cuts

on the short sides. The same technique mentioned above and shown below was used for all 4-sides. I did needto adjust and re-align the panel for each cut. An easier way would be to use a box-guide.





The power switch also needs a hole. Generally I use the same diameter and type of power switch (differentmodels, same dimension). The cut out needs to be ¾” in diameter, and although the rotary tool is quite capableof making this hole I favour the forstner bit.

Matthew Black has already issued the appropriate warning about the nature of these bits. It is akin to grouse-hunting with a bazooka. Even in the face of such overkill I still use the bit as it makes a clean hole that is mucheasier to manage than the rotary tool. Small diameters can be difficult with holes that can not be seen as theyare being cut. This is the case with such a small hole; the tool and the guide completely block the line of sight.One can over-come this by cutting from the underside, but my experience is that holding the rotary tool upside-down whilst cutting means one more action/movement that must be monitored. I used to do it this way until Iwas able to purchase the appropriate forstner bit.

That thing even looks mean… doesn’t it?

It is prudent to note that the initial drilling needs to be done a little slower and with less pressure. Once the bit isshaving material off and has sunk in about 2mm then the rpm of the drill can be raised; one reason to go slowlyis that the bit will have an inclination to travel until seated within the hole it is cutting. 6. Polishing



Once all the cuts have been made and all the profiling is done it is time to attend to the finer details.

For the most part 400 and 600 grit sandpapers are sufficient to get a nice smooth, satin finish. Occasionally Ihave needed to use 240 grit sandpaper to remove particularly deep clefts or bit-marks (deep being .5mm).

For small detail work and to square round cuts that were made by the router bit I use a set of small files. I alsouse some home-made “sanding blocks” as well as the real deal. For contours that I wish to remain round I usethe round file.

And, although not used in this project, larger panel edges can be sanded using an orbital sander to expeditethe process. Note that after using this tool a quick hand-sanding will be required so that all grooves in thepanels edge from the sanding are running the long axis, and not swirled or circular as those types of marks donot polish out readily or as well as the previously mentioned direction. The orbital sander is generally used onlywhen more aggressive sanding is in order.



To finish off the polishing procedure I use a drill with a muslin wheel attachment, or a rotary tool with a similar but much smaller attachment. The block in the middle is rouge, a polishing compound that is applied to thebuffing wheel.

The image of the fan hole below shows that results of a round-over router bit prior to sanding.



And here is a straight edge that has been sanded to a finish that is ready to be polished. Before polishing thefan holes, they were also sanded to a similar finish.

When polishing I travel back and forth across the edge at a leisurely pace. I also switch sides, meaning thebuffing wheel rotates in both directions along the edge. Generally the last pass will be in the same direction asthe rotation of the buffing wheel as this leaves the cleanest finish. The same technique is used when polishingthe inside rim of fan holes. It is also advidable to run the buffing wheel perpendicular to the edge so that theroundover termination point is thoroughly polished. If an area is not as clean as the rest it can always betouched up later.

When polishing flat edges care should be taken when reaching the corner of the panel, the buffing wheel can

“bite” into the corner and kick outward. In the image below, the wheel is spinning in a clockwise direction so thecorner that would catch would be the one on the right; were the wheel to be spinning counter clockwise, thecorner to watch would be the one on the left.



Here are some shots of the polished edges.

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The final polish is done with a micro-fibre cloth and a cleaner specifically for plastic and anti-static.

Next up: Capillary bonding.

7. Bonding (and Polishing Addendum)

but first an addendum to polishing.

There is another way to get a fairly clean edge that has been cut: Flaming. The results of flaming are not asgood as the results one gets from polishing, but it will be considerably quicker than hand-polishing withsandpaper, an endeavour that can be quite time-consuming, and may result in an uneven edge.A clean saw-cut should be smoothed out to a satin sheen with 600-grit (or higher - the higher the grit, thecleaner the outcome) sandpaper. Using a small butane torch, fan the flame along the edge to be polished. The

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flames tip should not make contact with the acrylic itself, only the heat. Generally I will have to run the flameacross the edge twice to get a decent finish; some experimentation may be in order.

I rarely flame edges anymore, but when I do this is the small butane torch that I use:

Here is a series of shots that show a saw-cut, the edge sanded, the edge flamed, and a comparison of a rawedge (very rough cut with rotary tool) and a flamed edge.

Note: these are not the same edges, merely examples.



Although not as clean and clear as buffer-polished edge, the flamed edge will do in a pinch.A “jet lighter” will do the trick, but a standard butane lighter will only lead to frustration, burnt fingers and mostlikely failure.

Bonding:Prior to bonding I will make one last check to see that all the components will fit…



Looks okay, please note that I also needed to account for ½” standoffs and wiring.

I use two products that for bonding acrylic: #16, and Weld-On #3. I rarely use the #16 as the Weld-On and thecapillary bonding applicator do a much cleaner and hassle-free job for me. Others may want to experiment tosee what works best for them.

Capillary bonding is fairly straight-forward.

» Fill the applicator about half-full» Hold the applicator upwards and away from any acrylic» Gently squeeze some of the air out of the applicator

» Invert the applicator and hold it lightly so that no pressure is applied» The applicator will start to return to its natural shape thereby drawing air into the bottle – this is how the flow

of Weld-On will be controlled.

Here is a close-up of the tip on the applicator.



Pressing the air out of the applicator.

Invert the applicator and hold lightly so that air is drawn inward.



Practicing on some scrap pieces will ensure that when the time comes to bond the panels for the theproject that the process will go smoothly.

When one is ready to to the bonding there is one common tool that will prove quite handy – canned air.

Giving the seam that is about to be bonded a quick (and light) spray from the air-can will remove any dust or debris that would otherwise get included in the bond; any foreign matter will be very visible.

Here is an image depicting the capillary bonding applicator and its placement when applying the Weld-On.



NOTE:The Weld-On will have a tendency to travel along the seam. This is a boon and a bane; a boon as it assists inuniform coverage and a bane as too much Weld-On can be applied. Again, experimentation will find the sweetspot.Additionally, when reaching the end of the run of the applicator, release the pressure on the applicator prior toreturning the applicator to its upright position so that air is once again being drawn into the bottle. This willcease the flow and ensure that no splattering occurs. Here is a link to a short video that I made for a friend of mine. Note that the angle is not optimal as it does notshow placement of the tip. The previous image above shows proper placement of the applicator tip.

http://www.youtube.com/watch?v=gfgDnlOabEc Here are some images that show the bonding process of the panelsNote that the vertical panel rests on the horizontal panel. This makes the bonding process easier, but there is atrade-off in fit-an-finish; the seam is visible. The point is almost moot as if the cuts are straight, the finish isclean, and the panels are aligned properly only the most discerning eye will notice the seam between thehorizontal and vertical panels. This is especially true with Black acrylic.

Note that one could bond the panels with the what will be the vertical plane on the horizontal surface, but whenit comes to load-bearing panels I try to avoid adding shearing pressure to the structure of the case. Havingvertical panels rest on horizontal panels eliminates that issue.

http://www.youtube.com/watch?v=gfgDnlOabEc

http://www.youtube.com/watch?v=gfgDnlOabEc





Note: Generally I will leave the protective sheet on the acylic panel until the last moment. In this situation Iremoved the protective sheet so that the work would be clearly visible. Now that all but the rear panels have been bonded it is time to start thinking about some of the other aspects of the case.Feet: I decided to use some feet that were not home-made. To mount them I did not use the stock hardware,but used some materials that I had in my hardware box.

I chose the flush-mount t-nuts as I did not want any protrusions on the inside of the case.





Another and more economical solution to feet are drawer and cupboard pulls. This type of Home-hardwarecomes in countless shapes, sizes, designs, materials and finishes - in short: There is something for everyone.Below is an image of some plastic drawer pulls that cost about US$ .90



Now that the feet are in place I can start loading the hardware into the case and fabricate the HDD/Optical drivemounting panels.

8. Case Cooling and Acrylic Optical and HHD Caddy

Drilling holes in acrylic can be tricky if one does not use the acrylic-specific bits. Standard bits will get the jobdone, but chipping on the entrance, and cracking on the exit of the hole is common. To assist in drillingholes that are chip, and crack-free I use a small drilling block that I made from a raw stair-tread. As you cansee… my aim is terrible…

When I drill holes for mounting components, I generally use the component itself (or one that is exactly thesame) as a template. I also use an angle to ensure that the fan will be aligned correctly with the panel that it ismounting to.

http://custompc.co.uk/blogs/syrillian/2008/06/22/case-cooling-and-acrylic-optical-and-hhd-caddy/

http://custompc.co.uk/blogs/syrillian/2008/06/22/case-cooling-and-acrylic-optical-and-hhd-caddy/



Here are the fans and the filters (I use the term “filter” loosely) that I will use on this project. I am a hibitual

cleaner of my cases, each week the entire crew gets a dust-off/out. That being the case, I am not too worriedabout filters, I am more concerned about airflow. These filters strike a nice balance between restriction andfiltering.

Installed:



Running with the lights out:

As you can see the lighting in this case will be minimal.

Drive caddy:This can be one of the trickier portions of custom building, especially when working without plans. The very firstthing that I do is to determine which corners on the panels that I am going to use are indeed 90-degrees. I markthese with a box so that when I am handling and turning the piece over and around, I do not lose track of whichof the corners is the leading corner (facing front, and on the bottom).





For what it is worth, I acknowledge that this is somewhat of a low-brow solution, but it is simple andstraightforward; a good way to start.

This holds the drive caddy in place, and when combined with some hardware the caddy can be fully locked into

place.

When I flying by the seat of my pants, I build around the components; but I ensure that the components can beswapped or replaced without having to break any part of the case. In this situation the HDD cooler becomes themainstay of the two vertical panels that will ride on the rails.

First off I needed to do a little mod to the Zalman HDD cooler. The HDD is going to sit outside of the airflowinside the case; I was concerned about heat. In the end I decided to use an old fan that I pulled off of a CPUcooler.



That should do the trick.

Again, I use the component itself to measure out and verify the mounting holes to be drilled.



The caddy is a simple affair that mounts the HDD vertically, and the optical drive in its normal horizontalposition. Both drives are mounted using the stock mounting holes, and some black allen-head bolts that havethe same thread size and pitch.

For anti-vibration, I use rubber washers on the drives themselves, and I use dense self-adhesive foam for thebottom of the cage panels.



Again, very basic in design with no room for upgrades such as added internal storage space…lol.Dense foam for the panels that comprise the walls of the caddy.



Rubber washers for the drives

And to control the fans:



Since I generally do not twiddle too much with the fan controls once I have the systems performance to myexpectations, I decided to keep this simple and install the controller on the inside wall with some genericaluminium stand-offs.

9. Last leg: The rear I/O panel.

The last panel to fabricate is the rear panel.The components are already in the case, so I measure and transfer the required dimensions to the acrylicpanel. I used the rotary tool for all cuts; the circle-cutting attachment for the 90mm exhaust fan, and the straightedge guide for all the other cuts.

http://custompc.co.uk/blogs/syrillian/2008/07/01/last-leg-the-rear-io-panel/

http://custompc.co.uk/blogs/syrillian/2008/07/01/last-leg-the-rear-io-panel/



After test-fitting and ensuring that all is in order I capillary-bonded the rear panel to the case.



One of the more tricky elements of working with acrylic is the gauge-to-rigidity ratio. The thinest thickness thatI use is 1/8″, a thickness that is considerably beefier than steel or aluminum but lacks the rigidity of acomparable gauge . This can pose a problem when it comes to the mounting brackets on any expansion-slotcard, and the securing of it cleanly.

For this build I kept it simple by making an “L” shaped panel that securely holds the video card in place. Thepanel is mounted to the backside of the case using removable/replaceable hardware; should I ever want to addanother card I will modify the existing panel, or fabricate a new one.



There is no slopiness in the card at all insofar as movement in any direction. The case can be heldupside down (and shaken gently) and all components remain securely in place. I would have prefered to bond arail across the backside of the PCI opening, and then mount the expansion-slot cards with thumbscrews . Werethis a full-scale build with an ATX motherboard I would have done just that, but this was a simple build, so I keptit simple.

As I type this, the project is complete…. with one small exception that has proven to be a thorn in my side: Theacrylic veneer for the front of the optical drive tray. At the moment it is baren, and one can not tell unless thecase is in direct light. I have already miffed the job once, the router yanked the piece out of my hand. After chewing on the piece briefly, the router spat it out and sent it flying about 10 feet… *sigh* …I will make another one and then post the final shots of this project.

Below are some “after-thoughts”.I wanted the PSU to be more secure in its mounting in the case. What I needed was some more support. Imade some quarter-round-like pieces from acrylic that I ripped down and rounded over. These pieces will sit oneither side of the PSU, and give it some added support; they also make the PSU aperture a little less harsh onthe eyes.



This long piece is for the inside/back edge where the hinges mount. The acylic is only 1/8″ thick, and needssome support. Unlike the PSU supports this one is a requirement, and in order for the case to hinge cleanlythere needed to be more rigidity.

I will have the last piece cut, profiled, polished and mounted within a week, and then I will post pics of thefinished project.

Thanks for looking.

Documents

How To Build Your Own SFF case