Dumbbell and Kettlebell Tutorial


  • Purchase concretefrom hardware store.  Concrete ranges from $3-6 per bag.  Bags range from 50-80 lbs.  We recommend "High Strength Concrete" or "Fast-Setting Concrete" made by Quikcrete or Sakrete.
  • Pour concrete and water into bucket.  On the back of every concrete bag, they will tell you the water-to-mix ratio.  This will tell you exactly how much water to add for the entire bag.  That means if you have an 80 lb bag, but only need 40 lbs of concrete, pour half the mix and divide the water in half. 
  • Mix Concrete.  Using any standard gardening shovel or wooden spoon, mix the concrete and water together.  Be sure to get all the dry concrete on the sides of the bucket.  The goal is an "oatmeal" consistency.  Pro tip: Mixing 20 lbs at a time makes the mixing process easier.
  • Transfer concrete to mold one scoop at a time.  Every 2-3 scoops, make sure to tamp down and twist/shake the mold, be patient with this step as this ensures you fill the entire mold and it will weigh the correct amount. You will know when the bottom half is full when there are no more large air bubbles coming to the surface when you tamp and twist the weight.
  • (Filling the KETTLEBELL): The kettlebell is delivered in a box used to aid in the process of filling the mold.  Keep the mold in the box with the opening pointed up and cut off the top.  IMPORTANT: If you already opened the box, simply re tape the sides and cut off the top.  Fill mold one scoop at a time, making sure the handle is filled with concrete first.
  • (Filling the DUMBBELL): Once you have filled the mold with enough concrete that it is overflowing into the upper chamber, now is the time when you can insert the optional REBAR down the handle for extra support. We have found the Rock Weight mold is fully functioning without a rebar, but a rebar will give you increased durability and extend the life of the product. 
  • Keep filling the concrete to the top of the container.  Once again, make sure to lightly tamp and twist the dumbbell every 2-3 scoops until it is completely full.  You may see some smaller air bubbles rise to the top, the more air bubbles you can remove, the better. This means less air pockets as the concrete cures, which in turn, allows for even distribution and a better end product.
  • Final step: LET IT DRY!  That is it.  A fast-setting concrete will be functional within a day, but normal concrete will be dry in 2-3 days.  Even though the concrete may be dry, we recommend you avoid dropping your weights for 2-4 weeks until they are fully cure.  You can clean the mold immediately upon filling, but concrete will wipe off with a wet rag after it dries as well. 
  • Optional final step: Wrap dumbbell or kettlebell handle with black grip tape.  

     If you have any questions, email us at RockWeights@gmail.com!  

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