Friday, September 10, 2010

Kitty Playland

Introduction

This DIY project is a little different from the previous posts on this blog. Being a cat owner, I have to be mindful of the occasional couch or carpet scratching. Obviously we don't want our furniture turned into expensive scratching posts. Like other cat owners I have bought cheaper scratching posts that don't really satisfy the need to scratch for the cats and quickly end up being ignored. I have also walked the isles of my local Pet Shop and seen the expensive cat playland's thinking it would be great if it weren't so expensive, some of them running up to $300.

Credit for this design is shared by a friend (Brandon) and myself. We realized that we could build our own super-sized playland for a fraction of the price, especially if we were resourceful. The model built here is about the 5th or 6th one I have built, the design always changes depending on different requirements but the construction principles remain the same. Feel free to modify the dimensions to your own taste. Below is a more accurate drawing of what is built below:


Disclaimer

This project involves the use of power tools and sharp objects (screws and staples). Power tools are fun and awesome but if used incorrectly you can cause plenty of bodily harm to yourself as well as others. If you are using power tools that you are not familiar with, get someone with experience to show you how to safely operate them. Make sure you use appropriate safety equipment to protect your eyes and ears.


So Here Goes


What you will need:

Tools
: I used a table saw, chop saw, radial arm saw, 18V drill, jigsaw and an electric staple gun. The reason I used so many saws was simply because they were available to me, honestly you could get away with less, but it's dependent on the raw materials you have.

You will also benefit from a tape measure, drill bits, wood glue, clamps, right angle tools, and perhaps some sand paper [80-100 grit].

Materials
: The whole motivation here is to save money. For the build here, you will need enough 2x4 to glue together and make three legs, plywood for the shelves, about 2ft of 1x2, carpet scraps, hemp rope, 4" screws, 1.5" screws, wood glue and marking pens. Hopefully you have some of these items lying around. The most I have ever spent making this type of Kitty playland was about $75, the cheapest build was $40 [for the rope only].

If you can find scrap 2x4's, perhaps at a friend or relatives house, or a building site, you can ask if you can have them. For the shelves, I prefer to use 1" ply, but 3/4" plywood will also work. Carpet off-cuts can be had at many places for free, although I noticed more places are charging to make as much money as possible in the tough economy. Choose plush carpet over loop as claws can get caught in loop pile. Screw choice is up to you, I will list what I used here, but there are so many options, if you are unsure, ask someone who might know.

The overall dimensions for this playland are below as well as the dimensions for the individual pieces:

Overall [HxWxD]: 36 x 58 x 18
Legs: 34”
Shelves: 36 x 18
Shelf support: ~ 2 x 3.5

Optional: You can make it bigger, smaller, taller, wider, more or less shelves... well you get the idea an I trust you ca design the add-ons yourselves.

Sawing, Gluing and Screwing:

Start with a plan. I drew mine on paper and it took me about 5 minutes. It allowed me to think about specific cuts I needed to make and visualize what I pieces I was going to need. You’ll note the image below is not the same, as I had to modify my design before I got started.

Next, I glued my uncut 2x4’s together with wood glue and some screws to keep everything in place while the glue dried. Once screwed together you can then use a chop saw to cut them to length. Remember, if you don’t know how to use it, ask someone. These saws can take limbs off in seconds.

I used a piece of 1x2 and a clamp as a stop so that all my legs were 34” long. Check to make sure your saw blade isn’t going to hit a screw. 3 cuts later and I had my legs ready.

Next thing is to cut the shelves and the base. I used 1” ply. Using a table saw I set the guard at the desired width of 18” and cut 3 identical pieces.

Now, to mark and cut out the wood where the shelf is going to sit on the leg use a tape measure to find the centre of one side and place the leg on the shelf. Then trace around the leg. I also like to use a speed square to make sure my cuts are square. Since I use scrap wood, which is often bowed a little, I leave 1/8th to ¼ of an inch clearance for later.

Use a jigsaw or even a reciprocating saw to cut out the inserts. Once done you can screw the legs onto the base piece. I like to clamp the base and the middle shelf together, then while insert the legs into the holes you just cut. This is better illustrated by the image above / below. You will want to use a square to keep things at right angles, unless you like that wonky-look to your projects. 3 long screws will do the job.

Once the legs are attached to the base plate, we will want to then mount the middle shelf. To do this, I used 1x2 and cut them with a miter saw. Again, this is a wonderful tool for removing appendages so exercise caution. I cut 7 pieces as outlined below. These pieces can then be attached to the legs to act as a base for the middle shelf to rest on. Use 2” screws.


Before securing the middle shelf down, practice-fit the opt shelf to make sure that everything is fitting together nicely. If it doesn’t, you will need to make some adjustments. If all is good, I would go ahead and secure the top shelf with more of those 3-4” screws used on the bottom shelf.


When done, you will also want to run a few screws from the top-side of the middle shelf to secure it down. That should be it for the frame. Now it is time to cut out the holes that the cat’s can climb through. Really you only need to do the top shelf as most cat’s will ignore your carefully cut hole in the middle shelf and jump straight to the middle or top shelf. Use a square and measure your hole. You will want it to clear the legs by at least an inch.

Drill a pilot hole or two and have at it with your favorite handheld saw of destruction. Your work should leave you with something looking like this:

It’s now time to get to covering. I find it is easier to roughly cut a piece of carpet to the size you want it, then start stapling down. Once it is secure at one side, pull hard and staple on the opposite side. Then use the knife to trim up. There is nothing hard about it, it just takes time and patience.


The second to last step is to put some kind of covering over the legs. I have used carpet, but I have found that cheap hemp rope from your local hardware store offers durability and scratchability for the cats. I used 6 rolls on this one. After making several of these I finally found a quick way that doesn’t leave your hands raw. Take the rope and loosely wrap as much of it around a leg as you can. Then use both hands to tighten several strands at a time. Think of it as holding a basketball and then twisting at your wrists. You will get several strands tightened in one movement and cut down on handling.

Finally you can bring your creation in for your cats to enjoy. My cat’s just about wet themselves with excitement when they saw what I had. They recognized it (they’ve had 2 before) and couldn’t wait to get on it. As you can see below my cat actually couldn’t wait any longer and got on it before I had even moved it to it’s location.

So there you have it. It’s a cheap and easy project that will save you some money and your cat’s will actually love it and use it, as opposed to so many expensive store bought pieces of cat-furniture.

Friday, April 23, 2010

Fan Modding My Time Capsule

Introduction
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
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.

Disclaimer
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...

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.