Intro: Ikea Hack Cat Tower
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.
Step 2: Prepare Supports & Shelves
Then remove the nails by supporting the end of the board and driving the nails out the way they were put in.
After the nails are knocked part way through flip the boards over and pull the nails out.
If the claws on the hammer don’t seem to grip the nail well you can turn the hammer sideways.
If you want Alberto Santos-Dumont style alternating stairs you will need to use corner shelves and the angled end brace must be trimmed to make clearance for the cross brace. Simply lay the short shelf on top aligning the cross-brace and mark what must be trimmed. Trim the support with a saw or a saw and the chisel. If you insist on measuring, it is the same length as a short shelf, 19- 5/8"
Step 3: Assembly
The unit is braced with the topmost shelf and the bottom two shelves. The other shelves/steps can semi-float fixed at one end or be nailed solid.
If you choose to nail on the new crosspieces, pre-drill the nail holes because otherwise they are likely to split. Use a short shelf as a template for the correct length. The cross-piece will be upside down/reverse what the crosspiece on the shelf looks like “and” be sure and place the arm with the holes perpendicular to the shelf or they will be in the wrong place. You can use another crosspiece or shelf scrap to support the ell while you drive the nails through the shelf boards.
Now assemble the basic shelving unit.
Install a shelf in the bottom most holes, in the holes second to the bottom, and at the very top. Leave the second and top shelf bolts a little loose.
Square the tower by measuring from each outside top to the opposite outside bottom and making adjustments till the two lengths are within 1/8" or so. If you get it wrong your eye will tell you and you can fix it. Then tighten the top shelf. You can install the Ikea wire cross-braces now. If you are making the whole thing from scrap, you can cross brace with picture hanging wire trapped behind the screw heads.
If the shelf is where you will be keeping it, put the cinderblock on the bottom shelf by sliding it in from the side. This ballast will prevent an energetic pet from knocking the unit over. It is still a good idea to attach it to a wall with one of the ell brackets supplied by Ikea. Mine is next to a staircase so I simply tied it to a barrister.
At a height good for your cat to jump up to it, install the first long shelf or the first former corner shelf. If you didn’t nail the cross-pieces to the shelves, use one of the cross-pieces to support the shelf by bolting it between the uprights with the ell upside down/reverse what the crosspiece on the shelf looks like.
Install your second about 12” up. Continue with as many corner shelves and crosspieces as you have.
Now entice your cat to use it by placing food on the shelves. My cat doesn't care to climb, so I used some of it as a displaay shelf for my two hand crank sewing machines.
Step 4: Bonus - Cat Perch
Cat perch from 12" concrete form
I have seen people ask about making cat perches and started on an Instruable based on what I remembered from a book I once had. I managed to lose half the pictures I took so I am going to just add in how I made the single level cat perch that is on the right. There are examples all over of more complicated ones, using three posts and cantilevered perches they can be made pretty tall. Add in a hammock or covered tube. Be creative.
The only way to make one cheaper than a commercial one is to scrounge as much of the pieces as one can. I got the carpet when an apartment complex near me installed new carpet. I got the 4X4" posts as the cut-offs from a neighbor's deck project. I purchased the tube, sisal rope, and MDF base. I used the MDF for the weight.
12" concrete form
2 each 4X4" posts
2 each3/4" X 2' X 2' MDF for base
Hot glue or reasonable facsimile.
Straight shank wood screws
Hot glue gun
Never put your hand/body in front of the knife! If you forget you could be making an expensive trip to the local emergency room on the 4th of July resulting in both an interesting drive and conversation piece. It will hurt and you probably won't be a priority. So you can expect to wait a while elevating the appropriate body part, which you practiced on the drive to the ER, while applying direct pressure. Don't ask.
Start with a new blade in the utility knife. A sharp knife is safer than a dull one as it won't have to be forced.
Cut off a length of the tube that will work for your space, ~ 18 - 24". Measure around the tube and mark off every 12-1/4" or ~ 32 cm. Use a carpenter's square across the factory end to make parallel lines. Cut the tube down each line. You will have three pieces. If they aren't perfect, no worries. Carpet will cover a lot.
Glue all three pieces together by stacking them. Now you have a reasonably stiff perch.
Screw the two 3/4" X 2' X2' MDF pieces together
Cover the perch and base with carpet.
For the perch cut the carpet about 8" longer than the perch and long enough to follow the concave and convex curves. Center the carpet so there is a 4" overhang on each end.
Glue the carpet to the concave/inside of the perch 1st. Then fold over the overhang and glue it down. Use clamps if you have any, weights, or else just hold it till the hot glue cools.
Now glue down the convex side up to the edge of the overlap. Carefully trim away the carpet so it matches the folded over carpet.
For the base, cut the carpet about 2' wider than the base width/length + the height of the base.
Center the base on the carpet.
Fold over two opposite ends of the carpet and glue them down.
Fold over the other two sides and trim in the corners. You can trim in the corners by:
• Cutting tabs to fold under the adjoining piece.
• A miter cut to both pieces to meet in the corner.
I found cutting the pieces to meet in the corner is easier and is also easier to mess up with an angled cut and a resulting gap in the carpet.
Prepare the upright posts. I drilled a hole the size of the sisal rope and then hot-glued about every 4th wrap. You can also use carpet.
Place the posts about 1/3 and 2/3 of the width of the MDF apart. Screw the posts to the base. You can screw up from the bottom or toe-screw them. If you screw up from the bottom you can first screw the posts to the base and then screw the second piece of the base to really lock in the screws. I didn't bother but I did drill pilot holes through the MDF.
Screw the perch to the posts. If you pull the carpet threads aside when you drive the screw the head will be covered fine.
Wait to see if cat cares. It took Bella the Almost Black Cat about a month to decide it was a cool place to hang out.