I am on a speed rope building spree lately, trying to figure out simpler and cheaper ways to make it so everybody can duplicate if they want one. The previous jump rope I've presented in another instructable was a bit short for a beginner and I had to use it a couple of weeks as I didn't want to create another one of the same kind.
So I came up with the present design that would resemble the slimmer handles the commercial speed ropes feature and also, as with the previous iteration, the cable is perpendicular to the handle and it effortlessly adapts its angle to accommodate the direction of the rope.
You can follow this long explanation in the sketch inserted in the image above. The active revolving component is made of a countersink bolt, a washer, a dowel piece and the appropriate nut. The cable goes through a 3mm hole made into the washer and is pinned onto itself with two zipties. It actually looks better without any shrink tube or tape for hiding the zipties (which I used on my other rope). The whole cable-washer assembly rotates around the axis of the bolt, while the countersink portion allows it to tilt to a certain degree and thus to follow the rope in a more free way than the cable-through-handle basic ropes.
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Step 1: List of Materials and Tools
- 1kg Yogurt Recipient
- Dowel about a index finger in diameter(you can really use a finger-thick branch that has a straight portion)
- M6 countersink bolt with nut (x2 for both handles)
One could safely use a nail with proper head and bend its tail after it went through the collar
- Washer (a sturdy one, with the inner diameter of the hole as close as possible to the bold diameter; x2)
- Clothesline with steel insert
- Smallest zipties (twisted wire anyone? -can be done)
- Drill with a 6mm drill bit for wood and a 3mm bit for the washer
- Stapler(again twisting a piece of wire around the handle and collar would squeeze it enough)
- Tape (some glue and twine rolled tightly around the handle while gluing it down would work too)
- Pair of Pliers or Wrench and whatever the bolt head requires, mine needed an Allen Key
- Some sort of saw to cut the dowel to the appropriate length
Step 2: Cut Off the Top Lip and the Bottom of the Can
I used the cutter to trim the lip off and then switched to a scissors to cut the cylinder along the seam and then to cut off the bottom. This part needs improvement as I ended up with a very jagged contour which shows in the end product and it doesn't look pretty.
Step 3: Roll the Flexible Plastic on the Dowel and Tape to Prevent Unrolling
The rolling should be done very tightly and make sure you don't let it unroll even a bit, as that will increase the diameter at the top and the dowel will not make a snug fit. You will see later what I talk about, mine is not perfect and it shows.
Step 4: Prepare the Dowel Collars
I am using a vice to cut the dowel to the desired length but other solutions are possible in case you don't have a vice, for example using a F-clamp and a chair, like exemplified in the picture above. Make sure not to tighten too much as you'll end up, like myself, with a cracked collar. The hole should be a 6mm just as the bolt. My wood drill bits were lent to a friend so I ended up doing some extra work to enlarge the hole which I did with the metal drill bit I also used to pierce the hole into the washers.
Step 5: Drill a Hole to the Washers
At this step I thought I'd use two holes and drive the cable through both so I don't need to have it pinned in any way but as nice as a solution (inspired from some commercial ropes I've seen on the web), it didn't prove feasible as the cable would impede the movement of the washer relative to the bolt (see the second image above). So I ended up using a single hole and pinning the cable to itself after I ran it through the hole (3rd image shows the final assembly of the active component of the speed rope). I don't have a file yet so I used the plate on the electric oven to scrape off any metal that would cut into the PVC of the clothesline rope.
Note: one important mention is that the wooden collar is calculated to have a length that would let some room for the washer to move and also end where the threading stops. This is to be able to screw the nut to these last threads and force it there using two pliers or one pair of pliers and a wrench (tighten it reaaaallly hard so it won't unscrew over time).
Step 6: Trim Handle, Staple the Dowel Collar and Tape the Handle Snug
Now it will make sense what I've told you at the beginning that you should keep rolling very tightly and tape immediately when done to prevent even the slightest unrolling. You should have difficulty inserting the collar back into the tube. Staple 3 times at about 120 degrees around the handle. Trim the handles' ends (the thicker part) to be the same length and tape starting from the top and continuing in a slightly angled way to the bottom, where you would cut the tape and go another couple of times just straight to slightly increase the diameter of the handle.
Step 7: Reinforce the Handle Bottom With Cork Plug From a Wine Bottle
Here you will have to make some manual adjustments of the shape/diameter of the cork plug. I used a cutter to shape it but if anyone has a better idea I am all ears. It was messy and it took quite a few minutes of trying, adjusting, trying, adjusting. You should really force the plug in the bottom hole, I actually hit the handle several times on the table so I make sure it is forcefully inserted and it won't come out easily (I did not staple this one).
Step 8: Final Product
Final thought: if you happen to be able to get some sort of Teflon or some other type of very hard plastic washer it might be a better idea as the clanking sound this makes is quite annoying when there is no music to provide the rhythm. But for the morning garage jumping session this is more than adequate. Play some energizing beats and see the pounds drop off like crazy. Have fun with the project and please comment and suggest any improvement you might think of. I am sure there are way more gifted makers in this community, if we collaborate we can make things even better.