Intro: Epic Playground Structure!
Name something to which all of the following apply:
1. is 24 feet wide, 12 feet deep, and 12 feet high.
2. is visible from space (well, Google Satellite view)
3. can be used to send children into controlled free-fall eight feet off the ground
4. is so heavy it doesn't need to be anchored to the ground
5. may be illegal where you live without a permit
6. Is nearly guaranteed to make your elderly neighbours freak out
If you answered, "jeff-o's Epic Playground Structure," then you win! Ten Internet points* for you! Over much of the summer of 2009, I spent most of my free time in daylight hours working on this (I built a laser guitar at night). There are enough pictures for a full instructable, but I figured most people would design their own version of this anyway, so pictures should suffice.
The structure consists of three levels. The top platform is about 5x10 feet. It stands about seven feet off the ground. From here, the twisty slide is accessible. It's also a great place to launch water balloons and science experiments from. In the future, the top will get a canvas roof as well. The middle platform is about 4x4 feet. A full staircase leads up to this level, and a ladder goes up to the top level from here. A smaller slide juts out from the corner. The bottom level is nicely shaded by the upper levels. Built into one end is a covered "rock box" - by lifting a section of the floor and latching it in place, the kids can play with the little pebbles inside. Mostly, the pebbles end up all over the place. Still neater than sand, though. A beam attached to an "A" frame on one end and to the main structure on the other supports four children's swings.
The basic idea here is to build the vertical potions in sections. After making a basic plan, I "sliced" it up into six layers. Each of these layers was built flat on the ground, then bolted together with carriage bolts to beams that run front-to-back. With careful planning, it's possible for one person to do this. I don't recommend it though, these sections are really freakin' heavy! None of this would be possible without the use of drilling templates. Before starting, I constructed three templates, sized for the 2x4 and 2x6 boards I was using. These allowed me to drill holes in the beams that aligned perfectly - or at least with a bit of encouragement with a mallet.
Once the sections were attached together in a basic frame, I attached the floor boards. Nothing special here, I suppose. The only thing to remember is that if you're using pressure treated lumber (as I did,) remember to use screws meant for use with PT lumber. Regular screws will rust out within the year. I covered the ground under the bottom floor boards with rocks to inhibit weed and grass growth, and to discourage furry woodland creatures from taking up residence. So far, so good.
The "rock box" is raised about 4" off the height of the bottom level. It is lined with weed-inhibiting cloth, which is stapled to the inside frame. The hinged lid was constructed separately, then attached using gate hinges and handle. When opened, it is held securely in place by a large bolt-style latch attached to the structure frame.
Safety railings are an absolute necessity - especially when the top level is seven feet off the ground! I bolted 2x4s all the way around, then screwed pre-cut railing balusters between the railing and the deck support joists.
The slides were installed according to manufacturer's instructions, with a few modifications. The twisty slide was purchased at Home Depot as a kit. It comes in a massive box, and you bolt all the plastic sections together before raising it into position onto the structure. I determined the height of the top level of the structure based on the height the twisty slide was designed for.
The last construction step was to add the swings. The main beam is two 2x10x14' beams, bolted at regular intervals on either side of a 4x4x12' beam. This forms a ridiculously strong and heavy I-beam - I'm sure I could hoist an engine block out of a truck with this beam. It is bolted on one end to the play structure itself, and is supported by a large A-frame on the other. Erecting the beam was quite a challenge. It was first bolted with a single carriage bolt to the play structure, then hinged up to meet the top of the A-frame. Along the beam are four pairs of eye bolts to support the swings. You can get some serious air on these swings - with the beam nearly 12 feet up, I can push my kids at least eight feet into the air. They love it. Their friends are terrified.
In the following spring (2010), after allowing the pressure treated wood to dry a bit, the structure was stained. We chose green and tan, but the tan ended up looking a little bit pink. Hrm. Well, I'll paint over it in two or three years.
So there you go. It didn't end up being too hard to build, though it certainly took time. A smaller (or heck, larger!) structure could be built using similar methods. The key is in the planning, and the use of drilling templates to make sure the holes line up perfectly. Now, go spoil your kids! There's fun to be had out there...
A miter saw
A big, powerful drill (preferably corded)
An impact driver (not necessary, but far more efficient at driving in screws than a drill!)
A set of wrenches for tightening bolts
Assorted "regular" drill bits
"Ship Auger" drill bits for drilling long holes through thick wood. Nothing else will work as well as these do.
2x4s, 2x6s, 4x4s, and other assorted wood as necessary
Hundreds of pressure treated-rated 2.5" deck screws
Several dozen 3/8" galvanized lag bolts, 3 and 4" long, and washers
Several dozen galvanized 1/2" diameter carriage bolts, 10" long
Several dozen galvanized 1/2" washers, lock washers, and nuts
Swings, slides, and other playground equipment as desired
Rocks or other fill as required
Outdoor-rated paint or stain as required
*points may be redeemed for two high fives in meatlife.