Step 6: Remove the Molds

After mushrooms have sat 24 hours (or longer if necessary), turn the bowls over allowing the concrete mushroom top to come out of the bowl.  Push the mushroom stem out of the tube.  If you have sufficiently sprayed your molds, the concrete should slip right out. 

Leave the concrete sit for another 24 hours to dry thoroughly. 
<p>I use WD 40 for easy release. Works great and makes clean up super fast!</p>
The best way to tell if your concrete has set up the right amount is with your fingernail or a screw or nail of sorts. Scratch the surface of the concrete (in this case it is the bottom of the shroom) If it really digs in easy it is not fully cured. Wait until it feels hard to scrape. Also your can drape a small plastic tarp over them and place a small space heater on the lowest setting to speed up the cure. After it come out of your mold if you are in no rush to paint your yard at you can fully submerge the pieces in a five gal pail for 28 days. If you do this the concrete will come out the hardest it possibly can providing you added the correct amount of water when you originally mixed it. Concrete is such a fickle and funny thing. It wicks the water off when cured for 12 - 24 hours and requires more water to continue the curing process for the rest of the 28 day period.
Thanks for posting this information about soaking concrete 28 days. I have molded a small chess set out of CONCRETE but they do not cure hard enough to avoid cracking and chipping. The 28 day soak may be the answer I was looking for. Thanks for the info.
another way to avoid cracking and chipping when dealing with smaller pieces like chess ones is to be sure to use a small aggregate. Use fine silica sand or the like to keep your mix as thin as possible yet still is binding enough to hold the sand together. Also be very mindfull of your water content when mixing. Just because it flows into your tiny mold easier may not be the best way to determine water in the cement mix. You want to add it slowly and when it just reach's saturation go a tiny bit further. it will still make a ball if you bounce it in your hand but leave wet spots on your palm. if it doesnt hold a ball your mix will be weaker then you need it to be. good luck in your casting adventures. Be sure to seal or maybe get a sample densifier from your local concrete shop. The densifier will also help harden your surface. if you plan on keeping the cast smooth finish. I am assuming you are not polishing them. (due to risk of breaking while polishing). Also for your mold I am hoping you are using a nice soft rubber for ease of detail and demolding applications.
hahaha.. very nice..like it much!
if you used a pvc pipe down the centre of the stem, added the concrete around it, it would be lighter, but probably still strong enough to hold the top. if you took a can a little larger than the stem, and set it in the top, spraying it with pam first, it should also make the top lighter and sit well with the stem, don't you think? i am definitely making some of these when i get the chance. i also think if you used some kind of &quot;filler&quot; to the concrete, anything lighter you have laying around, it would make it lighter, but possibly still strong enough, if you use the bath technique.
Love them. I'm off to try and make them now!!
haha,nice :P
This is a well done 'ible and I think I'll give 'em a try. I attempted to make a large stepping stone from the top of one of those plastic deli meat trays but didn;t have a clue what I was doing. Your 'ible explained it to me in plain english. First mix the quikrete properly, then spray the mold, then be patient (which I wasn't), then more patience and finally more patience! I can't wait to try all sorts of bowels and tubes. When you say you can use the pipe to make them tilt, can you explain that a bit better to me? Is the tube you're using flexible?<br />
<p>The tubes for the mushroom bases I use are hard plastic,&nbsp;and they're about 3 inches across.&nbsp; I use PVC pipe (like for plumbing) down the center of the&nbsp;plastic tube (mushroom base).&nbsp; After you've filled the tube with Quickrete, you push the&nbsp;PVC&nbsp;pipe into the concrete.&nbsp; You can either push it&nbsp;straight up and down or you can tilt it at a slight angle.&nbsp; I say slight angle because if you put it at a steep angle, your mushroom will look like it's falling over.<br /> <br /> You can also create a bit of an angle by pushing the PVC into the ground at a slight angle when your moshrooms&nbsp;are completed and you&nbsp;are placing them in your garden.<br /> <br /> A bit of advice on the stepping stones...they need to be about 1-1/2 to 2 inches thick or they'll break when you step on them.&nbsp;&nbsp; Also, for stepping stones, you want fairly straight up and down sides so the thickness is the same clear to the edge.&nbsp; I have used cake pans from Goodwill for stepping stone molds.&nbsp; BE SURE to spray them with PAM before putting the concrete in.&nbsp; I didn't use PAM when I&nbsp;trued to&nbsp;use&nbsp;this cute dimensional lamb cake pan to make a little&nbsp;lamb for my memory garden.&nbsp; I never did get the concrete lamb out of the pan, it was TOTALLY&nbsp;stuck!&nbsp; Have fun!</p>
Thank you. Now I even more curious about your memory garden! Can you send me a picture of it if I send you my e-mail address, or post it on your website? Oh and just so you know, I was up until 1 a.m looking at everything on Etsy. Now I have another addiction! LOL. Thank you for your great ideas and neat website.<br />
If you get some pretty big bowls and just line the sides on the inside of them you could make some real nice birdbaths too !<br /> <br /> But be careful when you paint them don't paint the inside of the bowl unless it's a non toxic paint to birds .....
Great idea!&nbsp; If you&nbsp;want a free form bird bath, I&nbsp;made&nbsp;one by scooping out an indentation what I thought would be an interesting shape&nbsp;right in the dirt in&nbsp;my garden.&nbsp; (Not too deep, you don't want to drown the birds!)&nbsp; Then I&nbsp;patted handfulls of concrete right onto the soil, molding the shape of the indentation.&nbsp; I made the bottom of the indentation flat so the bird bath would sit flat and not tip when it was complete and I mounted it.&nbsp; I didn't smooth the concrete out, but left it rough because I like that look.<br /> <br /> I made sure it was thick enough so it would hold up.&nbsp;&nbsp; They sell a liquid concrete bonding agent at Lowe's that I might mix in with the concrete if&nbsp;I were doing another bird bath.&nbsp; The bonding agent (about $6 for a quart) does strengthen the concrete.<br /> <br /> I pushed some colorful marbles into the wet concrete on the inside of the bowl to give it some sparkle.&nbsp; Then, I let it set for several days to dry and cure before pulling it out of the soil and mounting it on a tree stump.&nbsp; <br /> <br /> I just used a hose to wash the dirt off the outside of the bird bath.&nbsp;
pretty cool Do you think I could make a mushroom top&nbsp;table and mushroom stools using this method?
I saw a plastic child's sled at Goodwill that was kind of bowl-shaped.&nbsp; It was big enough for a kid to sit in it with his legs inside the sled.&nbsp; I thought of YOU&nbsp;when I saw it because a sled like that might make an interesting mushroom table.&nbsp; You could get one of those paper tubes from a home improvement store that are designed specifically to be concrete molds for a big enough base.&nbsp; Or you could use a log for the base.&nbsp; <br /> <br /> I would probably embed some chicken wire into the concrete to help reinforce the table top.<br /> <br /> I see two problems, however.&nbsp; First, of course, is that it would be extremely heavy.&nbsp; Second, the mushroom top is rounded (like a dome) not flat, so you couldn't really set anything on the table without it falling off.&nbsp; BUT, if you do make a mushroom table and stools, I would enjoy seeing photos!&nbsp; Have fun.
might get a tad heavy and not liftable by normal means<br />
I use wet sand to create a cap mold to get custom shapes.&nbsp; If you press stones, shells, etc. into the sand a little before loading in the concrete, it will become part of the surface of the cap.<br />
Nice!&nbsp; My mom's got these in her garden at her cottage, only difference is she dug a hole in the ground, placed a plastic bag in hole. filled hole with concrete, and then stuck a birch tree branch (obviously fairly thick, in as the stem.&nbsp; I like the birch bark stem look, but like your uniform shroom heads.&nbsp; <br />
Very Nice. I'm gonna make some and let the kids paint and place them.&nbsp; Heres an 'upgrade' idea. Put the PVC all the way thru the 'stem' and hang about 1 inch on the top and whatever you want as the steak on the bottom. And in the 'mushroom cap', center and sink a PVC&nbsp;end cap or coupler (that fits your thru pipe) that you drilled thru the sides and put a length (or two) of&nbsp;a wire hanger thru, bend it a little for stability, making sure that the angle of the stem-PVC matches the caps-PVC. This will allow you to swap caps, disassemble, etc. I personally will be using a coupler that I sanded the 'stop' out of the middle so it's deeper, for more support.
Very nice!<br />
&nbsp;I&nbsp;almost lost my whole paycheck to the metal ones in Lowes. I&nbsp;am going to try to make these if I've got any leftover concrete. Also I&nbsp;will have to remember that I&nbsp;can use PAM as a mold release for concrete. Great instructable.&nbsp; <br />
This is a really cool idea, Ill deffo try make those soon!
Must. Make. Mushroom ring.<br />
&nbsp;Very nice instructable but a concrete-filled soccer ball is the best yard art in my opinion.<br /> <br />
and painful to some unknowing people haha<br /> I wanna make that now, see how many people try to kick it<br />
Great idea; I've always seen these in stores, but now I can make my own!&nbsp;

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Bio: Married, 2 grown children, 3 grandchildren and one beautiful German Shepherd. I enjoy new projects and am always willing to take on a challenge...be ... More »
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