Friday, April 23, 2010

Fan Modding My Time Capsule

In my opinion Apple's Time Capsule (TC) is a fantastic little product. Since obtaining one in late 2009 I have not had to worry about the hassle of backing up both computers in our house as they are made wirelessly using Apple's built in Time Machine software. I could harp on about how much I like the Time Machine / Capsule combo but that's not the point of this post.

At the time of purchasing I was unaware of the major flaw in the TC's design: it's cooling system is rubbish and as a result, the device runs hot, shortening the life of the power supply. In my crude temperature measurements, during a 4 GB backup, I measured the surface temperature of the white plastic cover - directly over the power supply to be 109F / 43C. I think I have felt it even hotter in the past but with no measurements I can't back this up. There is a fix however, to modify the case so that adequate ventilation can cool down the heat generating power supply.

Credit for the modifications you see here belongs to LaPastenague*(Ray Haverfield) and Chris Fackrell**. Please visit their links for the original information I based my repair on. Both of these gentlemen offer a Time Capsule repair service if you live in Australia (Ray - LaPastenague) or the UK (Chris). Another excellent resource for information is the Apple Support Discussions.

I should make a short disclaimer that neither aforementioned or I are responsible for any damages you cause to your own TC or yourself should you choose to repair or modify it yourself. I imagine the moment you open the enclosure, if not when you drill the holes you will void any warranty you have remaining on your TC. Also, if you are not familiar with working with electrical devices and components you should either take the time to learn about them, get a professionals help or don't proceed any further. There is the possibility to seriously hurt or kill yourself with electricity.

So Here Goes
First things first I unplugged the TC and carefully placed it upside down on a towel to protect the original finish.

Figure 1. Under side of the Apple Time Capsule.

Since the TC was already hot, the silicon boot on the underside came off easy. Using gentle peeling action the mat came off easily and revealed the 10 screws needed to expose the TC's working internals. A few moments with a screw driver and I had the back-plate off. The plug for the fan can be easily removed by pulling it out.

Figure 2. Fan that is included in the Time Capsule. It's aimed directly at the hard drive, 90 degrees away from where it's needed most...

Being eager to modify something, I got hold of my trusty sharpie and marked the locations for the holes for the screws that fasten the back plate. There are ten screws...

Figure 3. Using a Sharpie to mark out the holes to punch.

To make the cleanest holes I chose to use a hole punch based on Chris Fackrell's recommendations. It just so happened that scrapbookers often use a tool like the one below and since my wife is a scrapbooker she happened to have one in her toolkit. She got it from the local craft store for less than $5, including two tips, one being ~5 mm diameter. Remove the silicon mat from the aluminum back-plate again and place it on a sacrificial surface like a piece of scrap wood. Take your time to line up everything so you do a good job.

Figure 4. Hole punch with exchangeable tips.

Next up, I removed the fan on the TC back-plate. If you haven't already done so, remove the fan power plug and then detach the fan by pushing the rubber grommets through with a 2 mm allen key, from outside of the the base-plate.

Figure 5. Approach for removing the fan from the back-plate.

Once the fan was off I used my trusty sharpie to mark out where I wanted the hole for the fan inlet. I drew lines as shown in the figure below so that the new hole would line up nicely with the inlet of the fan.

Figure 6. Use a punch to make a dent in the base-plate (I used an old screw) to make a clean pilot hole.

Once marked out, I clamped the base-plate and the silicon boot to some wood and drilled away. I used a 40 mm hole saw.

Figure 7. Clamping assembly for hole drilling. What a great excuse for using power tools...

Recommendation: If I could do this again, I would have done the following: used some scrap paper and tape and to protect the small holes during drilling. I didn't do it and subsequently spent 30 minutes with a pair of tweezers picking off metal shards from the sticky silicon boot.

Figure 8. Dozens of little metal shards that need to be removed because I didn't cover up the little holes in the base-plate.

After drilling I used a file and some sand paper to finish off the hole. I also took the precaution to wash the base-plate to remove any unseen shards.

Figure 9. All done! Next step is to do the electrics...

The next step in the whole process is to modify the wiring for the TC fan so that the fan is always on. The explicit instructions for this process can be found at LaPastenague's site. I chose to enlist the help of a friend to do the soldering. Rob did a stellar job for me, much appreciated!

Figure 10. Rob working on putting the resistors in the 5V fan line.

Rob had two 1/2 watt 100 ohm resistors (50 ohm actual) that he wired in parallel and soldered to the 5V line.

Figure 11. Two 100 ohm resistors wired in parallel.

We cut the two center wires to the fan plug and wired in the resistors. Once wired in, Rob did a nice job of heat shrinking over the resistors. We ended up adding about 20 mm extra length to the 5V side just to allow a more easy fit when reassembling.

Figure 12. Half of the fan modification is now complete. Next is to seal up one side...

Next up was to put something in place to protect the fan from little fingers. I cut out the protective grill shown below from an old power supply. Some mod's I have seen mount mesh or grills on the inside of the enclosure, I chose to mount it on the outside so that should something happen, the grill can't dislodge and move around in the enclosure. To direct the fans output to the power supply, you will need to tape over the outlet as shown below. I used packing tape taped to itself to make my cover.

Figure 13. Template for sealing one side of the fan.

Figure 14. Fan mod. The white patches were the well intended insulation.

A bit more electrical tape and the job was done. I added in some small foam pockets to my job. Perhaps for my own peace of mind, my thinking was it would isolate the fan from the circuit board below. Then I realized there was one more step to go.

As Chris Fackrell shows on his page, you need to shorten the rubber grommets that were originally holding the fan to the base-plate. This is easier than I thought, it's removing them that's a pain. I used a little Vaseline, a 1.5 mm Allen key and a lot of patience. Gently work the the small end of the grommet out. Be patient and you'll eventually get it.

To do the shortening mod, you'll need scissors and Crazy Glue (or any cyanoacetate super glue). I cut 5 mm out of the grommets and glued the two halves back together with Crazy Glue. This mod will keep the fan close to the base-plate and away from the circuit boards.

Figure 15. Shortened rubber grommets.

Insert the grommets back in the fan first, then use a small Allen key to push the fat end of the grommet through the base plate. The fan can be reconnected to the connector on the board and you should see the fan start up when you plug in the mains power.

Just for fun I thought I would see how much air is being blown. Using my Anemometer (for kiting) I measured a steady flowrate of 2 m/s. I also measured the external temperatures of the unit after it had been running for a while. I used a personal thermometer. This is probably not the greatest device to use for the mod but it gave me a relative change showing that the fan mod worked.

Figure 16. Anemometer measuring a flowrate of 2.0 m/s out of the modified fan.

If I put my hands near the upper vents on the outside of the TC I can feel a small amount of air movement. A good sign that heat's being removed by convection!

Figure 17. Exterior surface temperature of my modded Time Capsule.

Before the modification I saw temperatures of 109 F/ 43 C, possibly higher. A few days after the mod, the temperature seems to be stable between 94-98F / 34-36 C. Overall, I am really happy with the final result. I have the capacitors tucked away in case the power supply does crap out yet. I'll update here if I make any further changes.

Update** - I forgot to post these pics. Below you can see the holes punched for the TC base plate as well as the fan opening.

Figure 18. Time Capsule base plate and fan-mod opening.

I eventually used some stick-on feet from a local hardware store.

Figure 19. The final product working happily away.

Once again, I would like to say thanks to Ray Haverfield (LaPastenague) and Chris Fackrell for offering up their time and information to make it possible for people like me to do this themselves.


Anonymous said...

VERY nicely done and documented! As one of the US repairers-of-time-capsules and a beneficiary of Ray and Chris' hard won knowledge, I welcome you. My own approach was not as pretty but less troublesome. I remove the power supply and heat buildup to the outside by using a fairly bullet-proof Cisco supply (wall wart) and a Molex type adapter. A little bulkier but should work for quite a while.

Still, a tip of the hat to beautiful craftsmanship on your part.

Dale Mosher
Kissimmee, FL

Chris Fackrell (freddietheone) said...

Hello Nate,

Chris Fackrell here. As nice a job as ever I have seen. Very well done for have the courage to do the task (or have the 'bottle' as we Brits say!).

Thank you so much for your kind comments. I hope your TC will have a long and happy life. I like your anemometer, what a really great idea.

I have further plans to reduce the speed of the fan, to the slowest speed that gives the highest drop in temperature. This, hopefully, will make the TC with fan mod, almost silent.

Once again, many thanks and welcome to the TC repairing community.

Kindest regards,
Chris Fackrell

Nate said...

Hi Dale and Chris,

Thank you for your warm welcome and kind comments on my TC. I had a lot of fun doing it, my wife on the other hand was a little nervous about the whole ordeal - such little faith...

Chris, I'll be watching the forums and your page to see how you go with your experiments with further reducing the fan speed. Best of luck!


Adrian said...

Nice tut, I have read all 3.

I suggest using a PC PSU as an external power supply. This way you will have 12V & 5V on tap.
They have switchmode efficiency, with built in cooling fan. Hotwire the green wire to ground to switch on, remove excess cables, make a lead to go to TC.

While at it, fit a couple of USB sockets with the "resistor bridge" mod to enable iPod/Phone charging w/o computer or "iPhone" rated adapters.

Thumbs Up!


Nate said...

Hi Adrian,

Thanks for the comments. A PC power supply sounds like a good idea alternative for a failed TC power supply, especially if you could encase it in an aesthetically pleasing enclosure.

I haven't heard of the USB mod being performed, but that's a great idea, I'll look into it. Have you done this yourself?


Adrian Hawke said...

Hi Nate,

The PC PSU can sit under a desk etc, & run a cord up to the TC. Paint it black, stick rubber feet on the bottom if you want to pretty it up.

Yeah I have done a couple of the USB mods, works a treat. Basically, iPhones/Pods need a reference voltage to one of the data terminals at the USB end of their lead to tell them to charge.

Apparently this is a version of std USB stuff. To achieve it, find 2x high (K or M)ohm resistors, make a resistor bridge from the 0V/black wire/pin to one of the middle usb pins/wires, and then using the second resistor, connect from the SAME middle wire/pin to the +5V/red wire/pin.

Use the same value resistors to get exactly 2.5V reference voltage on the middle pin.

Use high resistance resistors so they don't draw any current. It doesn't matter how high, they are just splitting the voltage. 1/4watt or smaller is best for size. Fit the resistors to any existing USB power socket/adapter, or fit them to your PC PSU. I have fitted an in dash socket in my van to charge the missus iPhone & iPods etc by tearing down a 12v cigarette adapter & flush mounting a USB socket.

Works like a charm, no more hanging cords & adapters to find.


Ray said...

I have to get into the act and also say well done and very neat..

Certainly a lot nicer than my first efforts where I was completely in the dark,, and with Apple's wonderfully coloured wiring to help.. what did Henry Ford say.. any colour you like as long as it is black.

BTW a computer power supply will be very inefficient producing just 30W.. the very fact that it has to run a fan otherwise the switching transistors would fry tells you that. Excellent as a stop gap, but long term, the Cisco supply is available in amazing numbers on ebay, cheap as, well made and very efficient.
I disassemble them and recable it.. very neat and easy.
Ray Haverfield alias LaPastenague!!
TC repairer..

Nate said...

G'day Ray,

The only reason my mod is "well done and very neat" is because of all that hard work people like yourself and Chris put in so that people like me could have a try themselves.

I am hopping my power supply continues to serve me well otherwise I may end up doing your Cisco wall-wart mod.


Anonymous said...

Hey Nate, I wanted to say thanks for this tutorial... I linked to your site and (partially) used your tutorial in modding my own Time Capsule. I took a totally different approach for the power supply, I found it to be really ideal and keeps the Time Capsule pretty sexy, in that it doesn't have a typical ugly pc power supply sitting around (my power supply died), instead it just uses a typical 12V brick like most PC laptops have, which helps keep the heat external.

Check it out at my site if you're interested Nate, and thanks for sharing, I'm just followin' in your (and everyone else's) footsteps.

Thanks again Nate!


Anonymous said...

FWIW, the whole issue of a fan grille goes away if you just use the small holes already present in the baseplate as pilot holes, and drill a 4x4 hole pattern in the base using a 1/4" or 5/16" drill. No grille required, and you can either leave off the rubber cover altogether (for better cooling), or cut a square opening to go around the hole pattern.

Greenbeam said...

An elegant mod, thanks for the clear pics. One point though; the power cable is twin core only (no earth) so I think there should be no exposed metal on the device. The rationale is that if one of the live wires touches the case, it could be at a lethal voltage (in UK/EU/AU at least) without an earth to blow the fuse. This might drive you to using a non-metallic grille over the fan and covering over the screw heads (see Chris Fackrell's 'plugs' in the rubber mat). Cheers,

Post a Comment