This is a hack of Ikea GORM shelving for a cat tower. It was inspired by photos of outside cat stairs I have long since lost the link too and a need to keep the dog out of the cat food.
If you live close to an Ikea you can purchase the individual pieces. If you mail-order the pieces you may have to purchase a shelf set as a base unit. This Instruable can be built with only the Ikea wood parts to minimize wood working requirements. Some disassembly is required and you may have some pieces left over. If you have some scrap wood, a drill, and a 3/16” bit you will only need a minimum of three short shelves.
Note: I used more but 3 is the minimum. You can use either long shelves or corner shelves as the steps. Long shelves will be cheaper. I had some corner shelves I no longer needed so used them on my second tower. Once you get the idea you will see there are many ways to do this. I show a couple of variations at the end. Here is the list of Ikea parts I used:
4 uprights Width: 3 7/8" Length: 68 1/2" Thickness: ¾”
5 short shelves: Width: 19 5/8 " Depth: 12 1/4 "Thickness: 5/8 "
NOTE: Two short shelves will be disassembled for parts. They may be replaced with 3 each minimum ¾” thick by 12-1/4” long boards that will require drilling.
5 long shelves: Width: 30 3/8 " Depth: 12 1/4 "Thickness: 5/8 "
- OR -
1 long shelf: Width: 30 3/8 " Depth: 12 1/4 "Thickness: 5/8 "
Two corner shelve sets: Width: 29 7/8 " Depth: 12 1/4 "
One solid 3” X 12” cinderblock for ballast
NOTE: The fractions are metric conversions so are not as exact as Ikea states.
Measuring tool (tape measure, yard-stick, Ikea paper tape, folding rule etc.)
Small bit for pilot holes
(Drill Bits - Use a 1/8" for the hole in a home-made shelf support. If you want to drill a larger hole through the upright it isn't necessary but use a 1/4" Why? My handy Make: makezine.com Pocket Reference Guide by Thomas J. Glover recommends for soft woods a 55% thread penetration with the hole 1/8" deeper than the length of the fastener.
The Ikea wood screws shank and threads are the same width, 6mm or ~ 15/64" or .234 . This is also a size "A" bit. But we need a bit that drills a hole only 45% of this or .129. Well .1285 is a #30 bit and .125 is 1/8" or "Close enough." By accepting as Ikea does the need to thread the screw through the upright as well as the shelf support a you can get by with one bit.)
Step 1: Making the Steps
Start by dissembling two of the short shelves to use as the new cross-pieces for the cantilevered steps. I own a wood chisel so I used that. I recommend a wood chisel over a flat-tip screwdriver because there is a lower chance of digging into the wood. But a flat-tip screwdriver will work too. The cat probably won't care.
Keep your hand/body out of the path of the chisel/screwdriver, place the chisel close to the nails and using the hammer separate the shelf support boards (porch floor, it’s dirty). If you aim for the nails you will nick your chisel and be sorry. Don’t ask how I know.