This is a webpage about my atlas stone and Kettlebell / kettlestone making.

First off I must direct you to this stone making page. It describes everything I am doing for the most part with the stones. Making A Do-It-Yourself Atlas or McGlashen Stone

This is where I learned most of my technique and it shows how to do an atlas stone pretty well so I will go onto the kettlebell part.

I didn't think to take pictures of all the parts I started with or before I made the mold and I had to rush because of rain after I started pouring the cement so there are no pictures during that part of it. I will try to get more next time.

Firstly the cement I use is from home depot it is call Sakrete crack resistant, it is fiber reinforced to hold it together better in thicker layers without additional mesh or bracing. This is good for stones and kettlebells. I calculated the density of this cement at around 140 lbs/cubic foot.

I will go over the math of how to get the exact size ball you need for different weights outside the range of most common atlas stones as these are a bit heavy for kettlebells, unless maybe 2 hand swings with a 200 lbs stone, that could be pretty cool.

To make the math easier you can use this calculator for circle and sphere properties. It is the same one that is linked to in the stone making page referenced above.

So say you wanted a 100lb stone. You would start with the 140 lbs/cubic foot and divide 100lbs by this density so

100lbs ÷ 140 lbs./cubic foot = 0.714 cubic feet of cement required.

Now convert cubic feet to cubic inches because this is more convenient for selecting a proper ball size as they are measured in inches. Most computer calculators have a conversion function now to do this but if not this is the simple math for that.

0.714 cubic feet x 1728 ( 12" = 1', this is just 12 x 12 x 12) = 1234 cubic inches

Now the sphere calculator doesn't allow you to use volume as an input so it is easiest to guess a circumference # and go from there until you are close to the volume you want.

A 42" circumference gives a volume of 1251 cubic inches or a diameter ball of just over 13".

This is damn close but will be a bit heavier. The actual size of the ball will be difficult to get so exact anyways so it doesn't matter if the calculation is perfect.

If you need an exact # for whatever reason use the cube root of (Volume ÷ (4/3 x pi)) = radius. You can put this radius # in the calculator to get exact diameter and circumference numbers.

Now I used a length of pipe as the handle for the kettlebell. I choose a 1 1/4" pipe with an outside diameter of around 1 5/8" for a thick handle. You can make it bigger or smaller to suite you by using different size pipes.

I then used 3 pieces of 1/2" rebar I put through the pipe, I would try and use as many of the biggest pieces of rebar that you can fit through the size pipe handle you choose. Make sure the rebar pieces are well long enough to get down pretty far into the cement. The ones shown here are adequate I think but I will use longer ones in the future. You can always bend the ends around if they are too long to fit in the mold and they will be even more secure in the cement.

For a more accurate final weight, I would weigh all the other components, handle and rebar that are going to be permanently inside the kettlebell and subtract this value from the total you want BEFORE you do the calculation above to choose the correct diameter.

Anyways here is the plaster and cement I used.



Here is the plaster of paris mold after it was finished, with the handle and rebar I bent. Remeber to leave a hole large enough on the top to fit the rebar into the mold. I made mine too small and had to carve it out with a knife after it set. This is not so hard but it would be allot easier to mold it correctly the first time.

You might want to add some more plaster to level out the bottom of the mold so the kettlbell will sit up without rolling around like mine does with a totally round base. Remeber to make the ball a bit bigger in the planning stage to compensate for the cement volume lost if you plan on doing this though if you are concerned about getting the weight very accurate.









Here are some pictures after I poured the cement and molded it to the handle. Try and really pack the cement down into the handle around the rebar so it will be very solid when it sets.





Here it is after I broke it out of the mold and cleaned it up some. It still needs to be sealed and the voids filled with cement patcher. This could be helped some by vibrating the side of the mold before the cement sets to get the air out of it.



I also plan to fill the handle with jb weld to make a smooth handle, obviously the edges of that sucker would be pretty rough if you missed the steel pipe dead on or for 2 hand swings and the like. That and probably paint it when it has cured in a month or so maybe just to see how obvious it is that it is homemade out of cement when cleaned up and painted nice.

I know it's a bit crooked and sloppy but it is my first one, they will get better with more practice.