Pictorial guide/worklog of modifications to 'HTPC', GAM's Home Theatre PC; Making a cheap, simple case better - Page 3

By Greig Mackenzie

Some new hardware (fasteners)

I've come to know the good fellows down at Bomond Trading in Brookvale (NSW). Here you can see some long countersunk and socket head bolts, long thread screws and some 6mm aluminium tubing (not from Bomond).

I've come to know the good fellows down at Bomond Trading in Brookvale (NSW). Here you can see some long countersunk and socket head bolts, long thread screws and some 6mm aluminium tubing.

Top blow hole

Unfortunately my wife went to the cricket on this day and took the camera with her, so I don't have any in progress shots of the top blow hole.

My line of thought here was that I would reduce some of the noise by not having any open fan holes (other than rear facing). At the same time, I did not want to restrict the airflow. My idea was to place an acrylic panel over the fan hole, suspended above sufficiently to still allow good airflow. This would also prevent accidental spillages from dripping straight down into the precious PC.

So, long bolts, short pieces of aluminium tubing and slightly oversized acrylic cover. In the end though, I opted for some smaller diameter, black carbon fibre rod (from my sport kite building/flying days). The rod is cut and sanded fairly easily, whereas the aluminium can be a bit of a pain with these small lengths. The 'silvery' coloured aluminium didn't suit either, although I know I could have painted it.

Motherboard Tray Mods - Cable Management and CPU Heatsink Mounting Access

I just love cable management. One of my friends call me the 'Cable Guy' simply because he has seen me spend hours bundling, sleeving, routing and cable tying cables all around my home. Sometimes for good reason but often just for the hell of it. I don't like messy cables. No.

The plan here was to cut out a decent chunk of the motherboard tray so that I can get to the back of the motherboard and to access heatsink mounting bolts, etc.

Measure, mark and drill.

First I measured the approximate location of the HSF mounting holes. I really wanted to make it as big as possible as I know different motherboards have the CPU in different locations. I also bore in mind the strengthening ribs in the thin motherboard tray. I didn't want to weaken the tray unduly. Then I drilled the four corners with a 1/2" (12.7mm) drill bit to give nice rounded corners. Next, I joined the dots. It doesn't matter that it isn't totally square, the main thing was that the lines from one hole to the next were connected and reasonably straight.

For cable management, I also hastily decided on some slots and holes for the various cables that I wanted to route around the motherboard.

NOTE: Largest single hole, bottom-middle, for front panel USB/Firewire type connectors and smaller single hole (with grommet) for standard front panel connectors. The larger hole was cut using a 22.1mm? hole saw. Four additional holes drilled on the right to form the ends of two slots for SATA/IDE connectors.

Happy with my cutting lines, I attacked it with the Dremel. I started with the reinforced disc, but then went to the standard thin disc. Why? The thinner disc slices through this thin steel very easily and quickly and, when held so as to cut on the forward rotation, lower quarter of the disc, doesn't wear down unduly. The larger, reinforced, disc is too slow as it is cutting away more than double the amount of material. Not a 'biggy', but I preferred the standard disc in this case.

Cutting Technique - Always hold the tool very firmly or it will runaway from you and could easily cause bodily harm!

Cutting job complete. Notice the 8mm aluminium angle-line for reinforcing the now weakened motherboard tray. I tapped the angle for M3 threads. This was affixed to the motherboard using short 6mm M3 button head socket screws screwed into the tapped angle.

After a good deal of filing and sanding, we have relatively smooth edges on all holes and openings. Next step, rubber edge moulding.

 

The last time I performed this cable management mod, I didn't use any kind of adhesive to hold the edge moulding in place as it was the first time I had done it and I wasn't sure that everything was okay. This time I was more confident and decided to place small drops of Selley's Multi-Grip adhesive at each end of the rubber moulding and various spots along each length.

NOTE: I didn't want or need anything too aggressive as the adhesive is only there to hold the moulding in place for those bumps and when you're trying to insert stiff cables through right-angles, etc. The Multi-Grip performed appropriately. I also used the top of a small (derelict) screw driver to get the adhesive into the moulding.

 

For the edging on the heatsink access hole I applied pressure using my hands/fingers for a few moments. With the other holes I decided to be more inventive. Wedges out of the scrap timber box worked treat. The handle of a #2 Philips Head screw driver fitted perfectly for the larger hole.

Just to close off this little segment a little, I thought I should skip ahead and show you the finished motherboard tray.

NOTE: The upper slot on the right had to be enlarged to accommodate IDE connectors. In this case I didn't really measure anything like I should and simply guessed. I was wrong obviously. Without the edge moulding I would have been okay, but I don't like the sharp edges cutting into my cables. If the metal was thicker, it wouldn't have mattered so much.

NOTE: Once again, my impatience during this stage led to more errors. The heatsink mount access hole does not align well with the mounting holes of the motherboard. Last minute, I thought I'd leave a decent amount of material along the longitudinal of the midway motherboard standoffs and ended up obscuring the mounting right hand mounting holes. This will be evident in a later shot.