My own experience on cleaning up a mess,or,rather,an artistic anomally,would be to use either my Dremel or my angle grinder.It would depend on the mix you used-a coarse agg mix would require heavy duty grinding;on the other hand,a cement and fine sand mix is easy to deal with.I'd cut off with scissors the excess tape first,as close to the edge as possible,grind or Dremel the opening you want,then re-coat the edge for a clean finish.It's what I do with mine.I do two heavier coats,then a finish to fill in any bugholes.The openings tend to be larger,so a grinder is the best way for me.
Good luck on your showing.I'd be quite interested in the results!!
Cheers from here
Rick

Amanda,
You could also either cut close to the edge and use a little bonding agent and mix to finish the edge a little more, or fold the ends either in or out and using a little bonding agent and mix smooth it into the either outside or inside finish. By folding over the excess and adding a little more mix you will be strengthening the opening at the same time.
Looks great.
I had one heck of a fiasco with the one I recently did and it ended up much heavier than expected. On to the next one in a couple weeks.
Dena

artistic anomally..... I have to remember that, Rick!

Amanda - all the suggestions so far sound great. Let us know which cutting method works.. I am doing the same thing. (well, no lights or battery packs but I do want to somehow saw off the top of my latest big sphere so that I get 2 perfect pieces. I want to use the big one as a water feature and the smaller section as a shallow dish/disc). I will need to cut thru mesh and a quarter inch of quickwall.
Laura

Hey,Laura.Could you not just do 1/2 or 3/4 of a ball?I'm looking(again,we think alike!)at doing "dishes",from little to about 30 or so inches across(I'm getting larger spheres thru the winter,no way to do full size,but could do the dish).I can make any size opening,fairly round if wanted,by following the lines on the exercise balls.I make sure that whatever I use as support when I turn the partially completed ball over will fit within the rim I created.So,for example,If I'm using a 5 gallon pail to support the work,I go to the next largest opening,as dictated by the lines.I could go larger and larger so that I end up with only 2/3 or 3/4 of a ball to finish.
I'm thinking that,since the water features won't be operating in the winter,I might make a"cap" of some interesting colour and scalloped edge for a partial ball.Got one in the yard,looks sort of ,ah,interesting.Covers the opening,protects it in the winter.Course,we COULD have water flowing here all winter in our environment....
Cheers from here

Rick - good point! I hadn't thought of using the circles on the exercise ball but that would really help keep things even. As soon as I take the deflated thing to the gas station to blow it up again I will try that.
Meanwhile.... I think I will just take the saber saw and go at it.

Hey - is there any chance you could drape a big elephant ear leaf in such a way it would provide a cover for your water features? You could cast it and have a moveable cap.... Might get a rating better than "ah,interesting".

I do think it is interesting how often we are experimenting with the same ideas... makes you wonder if there are hundreds of us all over the planet wanting to make shallow concrete bowl/plates.
Laura

Laura-I was going to be a gas station attendee,but the local all purpose store had a sale on compressors,something like 50 bucks.Smallish,good with a Paasche airbrush,and inflates the balls nicely.I was using a bicycle pump...not any more!!
Cheers from here

Thanks for all of your great suggestions! Today's the day - I'm going to tackle that opening. I'll let you all know what works best.

I've been toying with the idea of an EE ball, as ltd mentioned. That'll be the next project. Going to need a bigger ball though.

I haven't even finished the first sphere and my little brain is off to the next.

Oh great. Fidel Castro farted or swallowed a chicken bone yesterday. Believe me when I tell you nothing is on TV but minute-to-minute updates.

So. Fla. is going to implode. Think I will go hide in my bunker with my dog, my spheres and a couple bags of portland til it is all over. Send FOOD (and vodka)!

A

for those of you looking for larger balls to mold on,try sportogo.com and go to replacement parts.They have 3 sizes of bladder(25,40,50 inches)at reasonable prices.I'm also thinking/wondering if you bought the balls from them,with their coverings,would that elminate the lines inside?
Cheers from here

Amanda,
I can't wait to see how your sphere turns out. What kind of a "mix" did you use or does any one else use for their spheres. Rick, I have read where you have a Mymud mix, however the ingredients you use, I can't find locally. :o(

Rick I Wish I had read this post before I went out and purchased a bicycle pump, just this past weekend. lol I will definitely be on the look out for the kind of deal you found. I would love to airbrush again. I used one when I did ceramics many years ago. Such a neat look. Not sure it would work for cement but I'd sure give it a heck of a try.
Carol

Carol-I've only used the ingredients listed in Mymud;however,if you check with Lowe's or some other large home improvement store,look for what laura uses-Quikwall.Plus,you have to use a mesh(EIFS)to be able to get to the thinner walled,lighter balls.You can,of course,make'm heavier,and I couldn't tell you what mix to use there-haven't tried it!
cheers from here

Rick Thanks for the information.
Carol

Well thanks to all of you, I remade the opening on the sphere. The original hole was not only an odd sized oval of sorts, it wasn't quite centered on the top.

I leveled the ball on the 5 gallon bucket upon which it was perched so that I could tell where the top really was or should be. I had a 7" diameter plastic lid that I placed over where I wanted the new hole to be and traced the form with a pencil. Some of the shape landed on existing set up concrete and about 1/2 was into open space where the original hole existed. (Is this making any sense??) I used my grinder with a 60 grit disk to cut away the existing concrete in the curve I needed and was left with an irregular hole.

{{gwi:71604}}

In a lucid moment I figured out that an inverted disposable plastic bowl put through the hole and then drawn up so that the bottom of the bowl would protrude through the hole but the sides and rim would be just inside would provide a great molding surface.

I used monofilament line through a hole in the bowl to draw it up, and secured it to whatever I could overhead, against the profile of the new hole I wanted to create placing little strips of drywall tape along the newly cut edge and luckily enough the rim of the bowl extended out where I needed it so that I was able to use it to place mix against it to complete the perfect circle.

{{gwi:71605}}

After curing for a few hours - Eureka!

{{gwi:71606}}

Keeping the new mix damp for a good cure was a challenge. Water spray and plastic bags didn't last long in the heat we are all suffering, but soaking cotton tube socks, placing them over the new area and covering them with plastic worked like a charm.

I am using a mix of just portland and light sand over stips of drywall tape placed directly on the ball. The ball is relatively light for its size and strong!

Now for the next question - I got a string of baby white lights and battery pack at Michaels (in the bridal section if anyone is interested). Since these lights and battery pack will be up under the rim, anyone of know of a quick-set adhesive that will hold them?

Thanks for all your suggestions and ideas! I couldn't have done it without you. Now, off to paint it!

A

Amanda - If you haven't thought of it, maybe next time you make a sphere you can attach your bowl onto the ball so that you can get your perfect circle all in one mix instead of having to do it in 2 parts.

Good thinking! I wish I had thought of that earlier. Planning is indeed important.

On this sphere the idea of leaving the hole open occurred to me after the fact. I like your idea though! I'm going to use it on the next one!

Thanks

A

Amanda - thanks for going to the trouble to make your progress so clear! That was a clever solution. It gives me an idea for fixing a mess I have made...

Your sphere turned out great. I sure want to see it lit up!
I have not tried what you are talking about so this is just a guess but surely one of the zillion varieties of tubes of contractors' adhesive would work for your project. Is there any chance a "shelf" could be fashioned out of transparent plastic to hold the light strand rather than trying to glue each light separately?? maybe there is a way to clue or cement on clips you could wind each light around.
hmmm. Once I tried taking fiberglass mesh and "weaving" wire thru it by making a sort of U shape with wire and pushing it through the weave of the fiberglass so the bottom was caught and secured by the mesh. When I concreted this down, the wire ends stood up and the mesh and concrete secured the bottom to the object I was making. This left the wires ready to do anything I wanted with them. That would be very simple and you could use your concrete to attach these wires anywhere you wnted along the edge of your sphere. The whole result would be invisible except for handy wires waiting to be used to hold your lights.
Would this work for you?
Laura

Amanda-I do my spheres in one go.In using a standard exercise ball,I work from a specific ringline.I go about concreting for a mimimum of 6-8 inches down from this line.BTW,I found that leaving about 1/2 inch of unmeshed concrete right at the rim makes for an easy trimming and tidying up.
Anyhow,when I get to my magical point,I invert the ball,and place the open area over a form that's an inch or so smaller in diameter .This form could be a 5 gallon pail,a specialized form that you construct,it could be anything as long as it's stable and slightly smaller in size.I've used bowls and such and find them not very stable.If you bump your ball,using something that has a very small surface in contact with your workbench,you may find your work of art will pull a Humpty Dumpty on you and you'll have major concrete surgery to do!Go for an opening,if possible,that's at least 1/3 of the diameter of your ball,minimum.Your worksurface will remain stable.Also,remember that the harder the inflation of the ball(that is,slightly overinflated)will give you a better,less yielding surface to work on.
"May the orb be with you!"
Cheers from here
Rick

Amanda - How did you decide to attach the lights?
Laura

Hi Laura,

I haven't decided how to attach the lights yet - I'm still working on painting the outside of the sphere. It is covered with large Dade County Pine trees, fields, crops, etc. for an upcoming show focusing on the "Spirit of South Dade" (Florida) We have the Everglades, amazing Biscayne Bay, and a lot of agriculture. I was inspired by another post to do a sphere featuring agriculture. Since most of the artists will be either submitting photographs or paintings I thought I would do something reallllly different and make a representational sphere. Here is a picture of part of it - before I removed the ball or started painting it..if anyone is interested -

{{gwi:71607}}

I'm working on getting the sky just right at the moment. I will post pictures when it is done.

So many of you have given me great ideas on how to hang the lights I can't wait to get to that point!

Wantmoreroses' sphere was amazing! Her first one too!

Stay tuned...

A

What a great sphere, I can't wait to see this done. Great idea,
Cindy

That is going to be AMAZING!!!
Will be waiting to see it finished.

Laurel

Neat idea! How do you do that??
Have you seen Dena's various recent concrete "crop" pieces? (peas in a pod - giant carrot - cabbage). You would love them..
Laura

Amanda-

I love your ag sphere! I can't wait to see the finished product! Be prepared for people wanting to order works from you at the show!

Good luck!

Jo

Buckyforce,
Thank you very much for saying that my sphere was good. I love yours. I want to try applying things directly to the sphere like yours. I can't wait to see the finished pics.
Vicki