For my son's first Halloween, I dressed him as Mr. Fredrickson from the movie UP. He was 9 months old, and cruising around the furniture like a pro, but unable to walk on his own without holding onto something. This costume provided him a walker, which he loved - and what's cuter than dressing a baby like an old man???
In total, this project cost me about $25, and a lot of the things I bought, like the clothes and stuffed dog, can be re-used. But your costs will vary, depending on what you have around the house to use (duct tape, clothes, stuffed animals, etc.).
NOTE: I've tried to be very detailed, so I've provided a lot of explanation of what I did and why. But you may not need all that, so I put the basic, down-and-dirty steps in bold italics throughout the instructable for easy reference.
Step 1: Building the walker: buy and cut the pieces
First, decide what schedule and diameter PVC pipe you want. I got Schedule 40, 3/4" pipe. Sch. 40 is plenty thick enough for most home and hobby projects, and 3/4" seemed sturdy enough and large enough for the baby to grab a hold of, but not so big that he would lose his grip. I found a 10-ft long pipe at Lowes for a little over $2.
While you are at the store, pick up some connectors. I used two 90-degree side-outlet elbows, and two 45-degree slip elbows (pictured), but you decide how you would like the walker to look/be connected, and get the appropriate pieces. The connectors cost me a total of about $2.
Now you want to cut the length of PVC into the pieces that you desire. If you have a table saw or a chop saw it is incredibly easy. If not, you can use a PVC cutter or just a hacksaw. I'm offering the lengths that I cut for my son, but please adjust for the height of your child (see the next step for how the pieces fit together in the final product so you know which ones to change). For reference, my son was 9 months old and about 28.5" tall. I cut 7 pieces, as labeled in the picture (don't worry about the duct tape or tennis balls yet; I just didn't get a picture of the pieces right after I cut them).
NOTE: If you cut the pieces the lengths I did, you will notice that the whole walker tips back a bit. My son was still putting a bit of his weight on the things he held onto when he was standing, so I compensated for that by tipping the walker back (and by adding weight to it, later). If you have an older child who stands on his own, you may not need to do this - in which case, you may be able to get two 90-degree slip elbows instead of 45-degree slip elbows, and make the front and back legs the same length. Because in my version the back legs (the 11.5" pieces) don't stand perpendicular to the ground, they are cut at an angle so that they lie flush against the ground. I did this by eye-balling them and marking where they needed to be cut after I put the walker together.
Step 2: Building the walker: fit test
Rather than bore you with written instructions, I've labeled the pieces in the picture with letters so you can see how everything goes together. Once again, don't worry about the duct tape just yet - that's the next step.
After you've assembled the walker, do a test with your child (or the child you are making this for) to make sure you don't need to make any more adjustments to the pieces. When your child is standing, what is a comfortable height for his hands to be at? Is the crossbar wide enough/too wide? Are the side rails deep enough/too deep? Do the back legs sit flush on the ground?
Step 3: Building the walker: duct tape! part 1
I recommend taking the walker apart first - it makes this step much easier. First, spiral-wrap each PVC piece separately, not worrying about the connectors just yet. Make sure you only wrap up to where the connector will hit (as shown), otherwise the pieces will no longer fit together. I found it worked well to wrap it all the way to the end and use an X-acto knife to cut off what I didn't need (I could easily get a clean edge this way).
Step 4: Building the walker: adding weight
I experimented with several ways to add weight to the walker, including pebbles, glass rocks (the kind from a craft store), and water. But what worked the best, BY FAR, was pennies. Rolls and rolls of them. I filled the whole walker with rolls of pennies from the bank (the old kind of rolls, that you fill and fold yourself, don't fit into 3/4" PVC very well, but the new rolls fit perfectly (both are pictured so you can see which ones I mean)). It took $13 of pennies to fill the whole thing, but if you don't want that much weight you can add less.
Cover the ends of the legs with duct tape to keep the pennies from falling out, and drop the rolls straight in, re-building the walker as you go along.
NOTE: I did NOT include the $13 of pennies in my original $25 estimate, because I planned on taking the rolls back to the bank and re-depositing them when I was finished. If this is not your plan, then please take that into account when figuring your costs.
Step 5: Building the walker: duct tape! part 2
The picture gives you an idea of how I taped the elbows: I wrapped a piece of duct tape around one side, then made slits in the tape so I could fold them down fairly flatly. This worked pretty well. I was left with the very corners of the side-outlet-elbows left to do, so I cut a small piece of tape and made slits in logical places to help it lie as flat as possible.
You're almost done!!!
Step 6: Building the walker: finishing touches
That's it - the walker is finished! That was the hard part - now it's time to assemble the rest of the costume.
Step 7: Finish the costume
You can dress your child up in a grey suit that looks just like Mr. Fredrickson's, and if you can find it, more power to you! But any grandpa-type clothes will do, and this is where you can really personalize the costume and get creative. I took a few trips to the thrift store and found the stuffed dog, a white button-up shirt, a black bow-tie, and glasses. The sweater vest and blue dress pants I already had. I initially painted the glasses black, but the paint kept coming off onto the baby's sweaty hands, so I took the paint off and used a permanent marker instead (as another idea, if you can't find any glasses, you can fashion a pair out of fuzzy black pipe cleaners). The total cost of all the thrift store items was about $11. I bought 6 balloons at Party City for $1 each (you can also get them at almost any grocery store) the day of, because the helium will only last for 12-24 hours. I tied the balloons to a carabiner and clipped it to a belt loop on the back of the pants.
Put it all together, slick your child's hair down with a little gel, and VOILA!
You'll have the cutest baby version of Mr. Fredrickson ever.