I have seen them done over a beach ball before on the mosaics forum and the concrete forum. I have never seen them done this way. I look forward to seeing your finished project.

~Micki~

That would be almost 40 lbs heavy.

dcarch

I have never done it with a basket or beach ball, but I have read that you need to support a soft sided ball because the weight of the concrete will cause it to sag, your ball won't be round.

I have done it with a glass light globe. You can crack the glass off when it's done curing. Couldn't be easier. Turns out perfect. Mine have been outside maybe 7 or 8 years, no problems.

I've made several concrete balls using basketballs.
You do have to support the rubber ball or
your finished ball will not be round.
I used a pile of damp sand for support.

Cut your hole where you fill the ball with air.
Also, there is slight support ribbing inside some basketballs,
so your finished concrete ball may have a slight ribbed design on it.

I waited about a week before removing the ball form.
Then I used a steak knife to remove it.. they are thick skinned.

I have made some solid ones and some hollow ones.
They are quite heavy.

I have always wanted to try something like this but without a house and yard, I don't have (1) a place to make it or (2) a place to display it! I really like garden2garden's idea of using the round light shades that you can find everywhere very cheaply.

I know they have tried something like this at the hypertufa forum here at Garden Web. You might want to try them over there.

Good luck and be sure to post pics once you try one!

My DH made this one a few yrs. ago ... he used an old basketball, concrete & a copper pipe down the middle so it could be a "fountain ball." (you can see the bball lines on it!) He had a 5 gal bucket with sand that he used for support while pouring it & drying. It's really cool! We buried a rubber feed tub in the ground, put an old grill grate on top & covered with rocks...small pump is in the feed tub. Good luck with your project! Jeanne S.

{{gwi:184089}}

good grief, I love that idea, here we go again. Nice fountain,,

Thanks for bringing this up Mjo. Learned a lot!!

dcarch,
You made me take the scale outside and weigh mine,
my solid concrete basketball weighs 32 pounds.
You were close...LOL

Lucy

No. Your scale is not accurate. If you weigh yourself on it, you are actually 50 lbs heavier. (only kidding LOL)

Serious, to make the concrete lighter, just mix with perlite.

dcarch

I have done that and when finished the concrete was flat and misshaped due to the weight.I had planned on making a lady bug but she can out warped(lol) I still painted her and used her anyways.

LOL- I never imagined that so many people had heard of this!!

Oh no.... my scale wouldn't lie to me... would it ???
I can't be 50 lbs heavier .. or am I ??? LOL

Yes, perilite would make it lighter...
I've heard of people filling the ball up half way and
then putting styrofoam in the center and then filling the rest of the ball up with concrete.

I bookmarked this page a while back...someday I hope to make one myself. Maybe you can benefit from teh instructions they give.

Here is a link that might be useful: Hollow concrete lsphere

Just MHO:

1. Styro foam to make the ball lighter will not work because it will float to the top. Very difficult to keep it down.

2. I seriously doubt smickerdoodle's link's method will work. In any case the end result will not be a smooth ball.

You may want to give this a try:

Fill the ball with only 3/4" of cement (sand mix, not concrete) wait about three days, rotate the ball and fill it with another 3/4", wait three days again, so on until the ball is completely filled. you should wait 7 days after the last fill, then cut open the ball, you will have a perfectly smooth light weight cement ball.

In this method, you will not need to support the ball with sand.

You may want to incorporate filberglas fiber into the cement if you want to make it extra strong.

You may want ot add color to the cement for each fill, the end result would be very interesting.

If you want to make more than one, just cut the basket ball in half, duct tape the ball together and fill with cement.

If you want to be really fancy, look up how to do terrazzo. It is easy.

dcarch

Jeanne, that's just beautiful! TFS the pic.

MJ, I saw some cool videos on youtube where people were making them .... huge ones even, can't find bookmarks at the moment though. I love the look of them all. Round is nice. ~tenderlee

Okay, I gotta try the styrofoam center to see if it works.
If the mix is heavy enough, it should hold it in the center.

I have made a hollow ball using the meathod in the above link. I used a large childs ball, slightly over inflated to make a firmer work surface. I used quikwall concrete instead of regular sand concrete and added quikrete concrete acylic fortifier to my mix... some people use Elmer's glue.
Quickwall is more expensive but creamy and easier to smooth. It is used for stucco type applications and already has polyester fibers in it. I used strips of drywall tape to make the finished ball stronger. Wait a few days for it to harden, slowly deflate the ball and you have a hollow sphere.
My ball didn't turn out perfectly smooth but good enough for me..it was my first attempted.
It's been outside in freezing snowy Michigan weather for about 4 years now without cracking.

If you have any concrete left, you can fill glass ornaments with it, wait a day and then crack them like hard boiled eggs and you have little concrete balls. Wear gloves and be careful not to cut yourself.

It can get addictive... I've made hundreds of them.

I have not gotten into ball making; but I will post another way of making very large balls in the next few days.

How about more than 24" very round spheres? :-)

dcarch

Here is a concrete ball I made from a light globe, I have smashed the glass off and have a pc of rebar inserted(during the pour)and will be making a cement pillar(from a cardboard tube you use for making them)and then of course mosaicing them!!!This is very heavy, and took a lot of concrete(at least 8"wide) but I wanted heavy so it's going great. Will make the cement tube thing and then have it to mosaic during the winter....

Here is a link that might be useful: {{gwi:184088}}

Looks great, calamity! Lots of good ideas on here! TFS! Jeanne S.

I am doing one now on a beach ball I am doing thinset because that is what I have I am doing about 5 coats of it I first used the wall fibeglass tape and added thick coats and then I put thick coats of it inside with chicken wire .I want to mosaic this so I do not want it to crack .It is prettty thick.I am using left over grout or thinset on it as I go .I hope it works LOL!!!

That sounds perfect Nana! Hope you post pics soon!!!

Okay, now I want to make a cement ball and a twine ball with poly stuff. Opposite ends of the scale in terms of weight! What wonderful info this site has! I'm heading to HD for the drywall tape. I make my leaves with the quickcrete with the vinyl..would this be okay for a hollow ball?

Here is a blog that shows how to make hypertufa/concrete balls.

Here is a link that might be useful: making concrete balls