Introduction: Jump Rope With Ball Bearings
don't feel like spending much on something so mundane as a rope with handles?
put handles on ropes yourself and save some money! this is a simple way to do it using ball bearings.
workout and keep fit without feeling stupid for spending money on something that can barely be called "equipment".
you will need:
1/2inch diameter PVC pipe (I had some lying around);
2 ball bearings - 12mm outer diameter (I had these for some time until I figured out what to do with them);
some bike handle foam (leftovers from a different project, they cover the PVC snuggly and provide good grips, costed me R$6 when I got it);
2,5mm electrical wire, no more than 4m length (at R$0,9 per meter, I got it for R$3,60);
4 rubber snug endcaps for the pipes (R$0,40 each);
some basic tools (hacksaw, pliers, snap-off blade knife, marking tool, a hammer, some sandpaper)
after gathering materials you should be able to do it in less than half an hour.
Step 1: Cut and Prepare the Pipes
this is basic working with PVC pipes, and it's pretty straightforward.
the pipes are gonna be your handles, so measure and cut two pieces of about 120mm with your hacksaw.
give it a bit of sanding to smooth the edges.
slide on the foam sleeves, they shoud be a bit shorter than the pipes, at about 100mm.
cut the tip of the foam sleeve at a 45º angle, so you can roll up electrical tape.
Step 2: Attaching the Ball Bearings to the Handles
so here is when the rubber endcaps and a tiny bit of skill come into play.
I found those at the local hardware store, they were perfect for what I needed, and very cheap. they are made of a rather hard rubber/plastic kind of material, and fitted well inside the handle. also, their inner ring fitted one of these bearings very snuggly. I love it when things work out so well like this.
the fit was very snug, so it wasn't immediately obvious how I would actually slide it in. I eventually did it this way: first I put the bearing all the way inside the cap. then the cap goes inside the pipe. when the cap gets to the point where the bearing is, it gets very hard to keep putting it inside, so I hammered it down. after it was all the way down, I cut the rubber with the knife, very carefully to make sure the bearing was in the correct place (it should be aligned and a bit further out than the tip of the pipe). for the actual cutting, the outer rim of the bearing is a very handy support.
the other 2 endcaps will go at the base of the handle.
Step 3: Determining the Cord's Length
not every jump rope is the same for everybody. the size of the actual rope changes with the user's height and arm length. there are a bunch of sources online that will help you with that.
a quick one is here: http://punkrope.com/how-to-size-a-jump-rope/
a slightly more detailed approach: http://www.rxsmartgear.com/how-to-size-your-rope/
google up and see what fits you best. remember that you can always make it shorter, but never make it longer; so make it a bit bigger at first and shorten it slightly each time, always testing to see if it is comfortable for you.
Step 4: Final Assemble
after finding ou the ideal size for you, cut the cord and clip an end of it with wire as shown. a simple knot won't work, as it will get bulgy and keep the bearing from actually rotating from inside. slide it through one of the bearings, slide the other one facing the first, and clip the other side.
slide the endcaps in the other sides of the handles and you're done!
final cost: R$5,20, considerig that I had most of the materials already. not bad - almost 10x cheaper than a similar store-bought jump rope, at R$50.