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peakpoet

A New Idea(?) Cardboard Mold (image intensive)

peakpoet
19 years ago

I guess I should preface this by saying that my balcony has become way too crowded. I'm now on a mission to make large planters to enable me to move a lot of the big plants off the balcony.

I've grown tired of trying to find large, stable and suitably shaped objects with which to make molds for large planters. And even more tired of struggling to release the planters from the molds after I've casted!

So here's my idea. I decided to make the mold out of cardboard, which is readily available where I work.

{{gwi:68564}}

Don't laugh, darn it! I'm just starting.

The planter form is 22" at the top and 20" at the bottom (it's upside down).

It's modeled after the large wooden planters they use in local nurserys here to hold mature palm trees. They're made of scrap wood and secured with some sort of metal ribbon.

Next step: wrap with duct tape to strengthen and protect the cardboard from moisture (another muck up I won't go into here).

{{gwi:68565}}

I've found it's good to do the bottom after the sides are complete. Remember the bottom is the top here.

Next is to wrap with my favorite - you guessed it! - drywall tape. :-)

{{gwi:68566}}

Here's the secret: next I coat it with plaster of paris.

{{gwi:68567}}

The POP is cheap, you can quickly slam it on and it dries quickly. Best of all, it really firms up the mold.

After the POP is dry I apply a thin coat of cement. By thin I mean 1/4" at most. The concrete should be quite wet and creamy; like clay, actually.

{{gwi:68568}}

This is really a huge planter but at this stage it still weighs less than five pounds!

peak

Comments (80)

  • tuanh
    19 years ago

    i am impressed!

  • eva1429
    19 years ago

    Peak, "It looks a little utilitarian" -- you're way too modest about your tufa talent. My first reaction was WOW! What a wonderfully textured pot that would cost a fortune to buy! Your sharing your process with us makes the end result even more impressive.

    And I'm with tuanh: I am impressed.

    Eva

  • Jilly_W
    19 years ago

    Peak,

    WOW! What a GREAT result with your planter, as Eva says, just think what it would cost to buy one like that.

    Jilly :)

  • peakpoet
    Original Author
    19 years ago

    Thanks, guys, I appreciate the compliments and am glad you like the planter. I guess we're all our worse critics.

    I feel like an idiot because I kept adding layers and layers to the planter and then, of course, it became too heavy to easily move off the balcony. So now I have even less room there! {{gwi:68577}}

    peak

  • Louisiana_greetings
    19 years ago

    Good job!! Hey Peak, how about a pic of balcony, plants and tufa all together?
    Bonnie:)

  • peakpoet
    Original Author
    19 years ago

    {{gwi:68578}}

  • olddutchman
    19 years ago

    Thanks for showing how it is done.
    I have a two car garage and it is as stuffed as your balcony, so I guess "space is relative".
    Michael

  • eva1429
    19 years ago

    Peak, I love it! A wonderful "floriferous, leafiforous, junglesque" balcony! But please, please restore that beautiful blue chair.

    Eva

  • Louisiana_greetings
    19 years ago

    Amazing,I agree with all the same stuff Eva said ;) by the looks of it, you don't have much room left, are you going to move into the living room;)
    Bonnie:)

  • Gambite
    19 years ago

    Great explanations Peak! As for adding 4 bags of soil....too heavy - yikes. One of my tricks is to collect those styrofoam chips uses as packing material. Or, one can use vermiculite or peat. I strongly encourage you to load up the bottom of the planter with a light-weight filler material. (I am unsure of the organic/toxic implications of styrofoam) but peat and/or vermiculite are fine. Then your planters won't weigh a ton and will regain their portable virtues.

  • peakpoet
    Original Author
    19 years ago

    Eva, the chair's not as bad as it looks. It is a bit dirty but easily cleaned - that's why I used the gloss clear coating. I took the pic in mid extensive cleanup/reorganization so once I get things straightened out everything'll look beyoootiful again. For maybe a day.

    Gambite, the soil actually didn't add much weight to the planter. It's a lightweight potting soil and, even though I added water-retaining crystals I had no problem moving the planter around. That baby's gonna be the honey tangerine tree's home forever so I made the planter that size so I could get me a good crop of that heavenly fruit. Mmmmm.

    peak

  • peakpoet
    Original Author
    19 years ago

    I actually broke down and bought a box for my latest project. As I was waiting in an interminable line to pay for it I had plenty of opportunity to read the proclamations about strength and weight capabilities imprinted on the side. So I made the mistake of not covering the box with duct tape. BIG MISTAKE. Once the cardboard gets wet it turns into mush.

    Big mistake = big waste of time.

    peak

  • eva1429
    19 years ago

    Peak, can't you turn it into a wonderfully organic flowing no-particular-shape pot with holes poked in it for sedum...or something? You're king of the masterful 'tufa recovery!

    Eva

  • peakpoet
    Original Author
    19 years ago

    Sorry, Eva, nothing so exciting. I'm just going to fix it. I'm too much of a cheap ba- I mean thrifty soul, to go buy another box. Besides they pissed me off making me wait fifteen minutes with no one else in line. I'll teach 'em.

    I ripped off the very thin layer of drywall tape/'rete which had caused the problem. I used a hairdrier to make sure the cardboard was bone dry. Of course as it dried the cardboard wrinkled but only on the one side of the box on which I had applied significant 'rete. So I double duct taped that side inside and out, single taped the rest of the box, applied fresh dwt and about 1/16" of 'rete. Just enough to barely cover the dwt.

    It must be my cement... the regular gray cement gives me a much better claylike consistency than the white. Which is strange because the gray is older.

    peak

  • DicktheHick
    19 years ago

    peatpoet ..... Hi!

    Know you just referred to this in another thread .....

    much worthy of a 2nd look by everyone ...... bumpity-bump

    Was just cutting a CheeseBits box up this morning, as a prototype for a new concept plant cuttings plastic container ..... I HATE PLASTIC ..... and here I am designing for that material !!!!

    Best to you in all you do!
    Dick

  • peakpoet
    Original Author
    19 years ago

    The technique I've described above involves wrapping four sides and the bottom of a cardboard box with duct/drywall tape, standing the box topside down, then applying the 'tufa. This has fatal results if you don't keep the cardboard dry, as I showed in my Tiki Planter post.

    When I made the Tiki planter I applied the 'tufa to one side at a time with the box on it's side, therefore exposing the bare cardboard inside. I misted the 'tufa, covered the planter in a damp towel and wrapped in plastic, effective trapping the water inside. This allowed the water to seep into the cardboard through the open top. Crack. Crumble.

    The solution? Completely wrap the inside and outside of the box with duct tape (safest), or make 100% sure any of the cardboard isn't exposed to water or wet 'tufa. One benefit of additional duct/drywall tape is that it makes the mold even stonger.

    Next: naphtha flambe and it's application as a cardboard demolding technique.

    peak

  • lonowl
    19 years ago

    Peak,
    Just a Thank-You for all the details on this, I have learned a lot. I too have no one to share my enthusiasm for tufa with. I can see this forum becoming addicting...

    lonowl

  • lonowl
    19 years ago

    hey I just tried this technique this weekend and boy was it fast! I thought it would be a total pain with all of the taping and layering...turns out, making the cardboard frame and taping it up is a perfect in-front-of-the-TV activity, when it's too dark to 'tufa outside, and I'm too fidgety to just sit still...LOL...I think I have a new disorder, T.A.D.D., the inability to hold still or concentrate on anything not 'tufa...

    anyway thanks for sharing the technique, I loved playing with the POP, so rewarding to slap it on so fast and set up so quickly...I put my tufa on the same day and they are curing now...

  • peakpoet
    Original Author
    19 years ago

    Lonowl, glad you were able to try it! What're you making?

    peak

  • lonowl
    19 years ago

    I am making 2 smallish planters, terra cotta pot kinda size. Also 2 medium-ish ones a couple feet tall but not very big around. They are oval and diamond-shaped if you look at them from the top. Pretty much I am just testing out the technique, but I am very excited about the shape possibilities. I am prepping some balloons with the dwt and POP too...
    L

  • butterflybush
    19 years ago

    Peak, I really like your cardboard Mold thread, I mean I really like that large pot. When I first joined this group, I wanted to make a large pot/trough. Still haven't. How did I get so sucked in and distracted that I have not done this??? I am gonna do one, right after my community project. Wish I had more energy. Days are getting tooo short, and too cold!! Couldn't you put a plastic trash bag on the box, and just hold it on with duct tape? Do you really flambe them off? Don't the neighbor's complain? BB

  • peakpoet
    Original Author
    19 years ago

    BB the POP serves to reinforce the box. For smaller boxes you don't need this but when you're huntin' big 'tufa game I recommend it.

    Another advantage to the POP is that 'tufa sticks a lot better than it does to plastic trash bags.

    HEY IF I CAN WORK ON A BLEEDIN' 60 SQUARE FOOT BALCONY YOU CAN WORK IN YOUR GARAGE OR BASEMENT OR WHATEVER.

    The stewardess across the way isn't home much and giggles when she catches me nuding up to warsh up/hose down. No one on the left, and the guy on the right just got a new gf so I could set off M-80's and he'd just think he just hit her g-spot. Folks above can bite an emu for all I care.

    Oh plus flambe during the day's pretty unnoticeable ;-)

    peak

  • lonowl
    19 years ago

    Yesterday I had a friend over to 'tufa YAY! She's not addicted yet, but at least she was willing to try it. She made a leaf and I used the rest of the batch to coat the inside of the carboard/pop things I had done.

    I was even able to *save* two of the tape covered cardboard molds since the opening on those were wider than the base and there were no undercuts. All I have to do is redo the drywall tape and POP 'em again! I don't know if it matters but I did not use duct tape but a clear kind that has fiberous "threads" in it. It keeps out the water just as well, but can't be torn by hand like duct tape (drawback). However, it was $1 for 10 yards of duct tape, or for the same price 3 times as much of this stuff, so I tried it and am happy with it.

    My pots are curing now...can't wait!

    L

  • dixiesmom
    19 years ago

    Bump

  • eva1429
    19 years ago

    Bump again! Some great ideas here, Peak. Thanks.

    Eva

  • joycevallee
    19 years ago

    What a great post. Thanks for all the pics and explanations of the box planter. I just got an idea when you were talking about moving the planter around and it's weight. Why not turn it upside down and cement some casters or rollers onto the bottom of it. Then you can boogie it all over the place.

    Just an idea...

  • sowngrow (8a)
    19 years ago

    This is interesting-thanks for posting your way through it all. Another idea for filling a large pot when you plant it, so the end result is not too heavy, is to use pine cones in the bottom before adding soil.

  • dixiesmom
    19 years ago

    I am trying Peaks method on some triangle shape planters IÂm making. I shaped the boxes, covered them with plastic bags, taped that on with duct tape, and then covered them with drywall tape. IÂm putting on a coat of thin set mortar mix first then will apply tufa, when I can move them outdoors. Waiting for the rain to stop. Hopefully since they have plastic under the drywall tape, the cardboard will come away easier and I will leave the drywall tape on, and maybe put a coat of tufa on the inside. Light weight is not a concern here, as I will not be moving them around. I thought they might look good with some ball shape feet under them when IÂm done. I will post them in the gallery when I get more done.

    Dixiesmom

    Here is a link that might be useful:

  • cheyjohn_z5
    19 years ago

    I am so thrilled that this thrilled was bumped and saved for all of us! I wanted to start making HT last year, but never found the time. With this tutorial, it looks so easy I think we will start soon. I think the weather isn't warm enough here yet though. Hubby has MS and can't walk very well anymore, but boy can he tape and tufa, I am sure! He is going to love this!

    The rollers on the bottom and/or ball feet sound interesting. I wonder how it would work if a design (simple square etc) was cut out of one or more of the sides. Maybe after the cement layer, but before the HT....

    This may help me to get rid of some of the rocks I have been complaining about too! I can add them to the outside when the last layer is still wet. Hubby and I can even use up the china we have saved and mosaic over the outside! The ideas are coming to quickly...I'm getting dizzy...

    Chey

  • imqtpi
    19 years ago

    Hey Peak!

    Seems this thread "lives on" - which is cool... Howsomever! I wanted to look at the Tiki Planter post. Clicked on the link (quoted below - circa August 31 '04), but Gardenweb seems to have "lost it."

    Do you have pics of said Tiki Planter? If so, where? I'd love to have a look-see!

    Thanks!

    -Nancy (who is looking for inspiration for *Anything Tiki!*)

    "The technique I've described above involves wrapping four sides and the bottom of a cardboard box with duct/drywall tape, standing the box topside down, then applying the 'tufa. This has fatal results if you don't keep the cardboard dry, as I showed in my Tiki Planter post."

  • peakpoet
    Original Author
    19 years ago

    dixiesmom, I love your triangle-shaped planter idea. The substitution of quickset for POP is excellent. I know Butterflybush has used some form of concrete which sets in an hour and it has worked well for her.

    Nancy, here's one of the tiki molds I've purchased which is available on eBay.

    Here are my pics on Photobucket:
    {{gwi:68560}}
    {{gwi:68561}}
    {{gwi:68562}}

    peak

  • hollyhockdoll
    19 years ago

    Hey, thanks everyone for bumping this thread!

    Peak, I'm curious as to how the famous (infamous?) "lightweight" planter survived your zone 4 winter. I guess my concern is that there was more cement than usually used in hypertufa, and did that effect how it handled freezing temps? I'm gearing up for my first 'tufa-ing weekend in about 3 years!!! I'd love to try this, but I'm not one to bring things in for the winter!

    love your tiki, BTW!!

    Jill

  • dixiesmom
    19 years ago

    My triangle planters are coming along. I know I've said this before, but THIS is my last big planter! I put a layer of quick wall on my them, but it was a year old and I didnÂt trust it, so I put another layer of thin set on them, and am now covering that with Tufa. So they are getting heavier. I don't know how I'm going to get them off the table. Embedding rollers on the bottom is something I'm putting a lot of thought into. Going to check out rollers next time I'm at HD.
    Peak, I'm also interested to find out how your planters are holding up. Did you take them with you on your move? If so how did that go?

    Dixiesmom

    Here is a link that might be useful:

  • peakpoet
    Original Author
    19 years ago

    Jill, I was living in Z10 Southern California when I made the planter last year. Unfortunately I had to quickly dispose of all my 'tufa when I sold my condo after my move to NY.

    Dixiesmom, so far so good. Spring has sprung!

    peak

  • Jermes
    18 years ago

    I am so happy I was browsing whern I found this thread on page 9. It probably would have dropped off pretty quick. If this helps it to stay a lttle longer, that's great. I haven't tried hypertufa yet but have been reading all the threads from you VERY talented people and one of the things, I have been really trying to figure out was a large square or rectangle planter. This one is so informative!! If you wanted the planter to have feet instead of rollers, could you add them on after the planter cures? Keep the good info coming.
    Jerrie

  • rickharmer
    18 years ago

    Tufa drills quite easily,so you could attach feet later.Screws plus,perhaps,glue to help the feet/rollers,stay on.
    So,Peak,what possessed you to move to the snow country?And,have you resumed your tufa addiction?
    Cheers from the sunny West Coast of Canada.

  • sweetiela
    18 years ago

    What a wonderful project...hope I can try this soon....Tammy

  • Dyas
    18 years ago

    Peak et al., I'm intrigued. My early readings about hypertufa included using cardboard boxes as molds, but they weren't covered in anything--they just served as the outside mold, with another box, e.g., filled with sand placed inside to maintain the proper structure. As the stuff cured, the cardboard got wet and soggy and you could just pull it off the next day as the tufa cured enough to hold its shape.

    Using boxes as the mold and putting stuff outside them is kind of a twister, but you've done a great job. The photos are clear and easy to follow, too. One question: Did you put the extra coats of tufa on because you felt it was necessary or because you wanted to? I can see where having a more thin-walled piece could be very useful in many situations.

    Thanks for sharing this!

    Anna

  • tufaenough
    18 years ago

    Anna the 1 1/2 inch thick blue or pink styrofoam make excellent strong waterproof boxes at a very modest cost.
    Probably less than the materials needed to make a cardboard box waterproof.
    And tufa doesn't stick to the styrofoam so it can be removed and used over and over again.

  • peakpoet
    Original Author
    18 years ago

    Jermes, if you wanted square "feet" you could cast four individual cubes. After they'd cured you could set them in place, drill a hole in them into the 'tufa, then use 'tufa as both a mortar to secure the feet into place and also stuff it through the hole to make a sort of dowel. There's also plenty of epoxy and Weldbond's More Than Just Glue to secure, but that'd be too easy.

    rickharmer, I needed a lifestyle change. The pace here is wonderful. I'm working on a couple of little projects but am moving at a glacial pace.

    Dyas, ButterFlyBush had the idea of using quick setting mortar right over the DWT and skipping the POP. That sounds like a winner, but the planter wouldn't have the voids crated by the decomposed peat moss on the inside that the plants like so much. I put the extra coats on mostly to even up the shape. You can get pretty thin if you use admix and a very dry 'tufa mix.

    tufaenough, my motto is, "cheap is good, free is better." I happened to have these materials around or with easy access but didn't have access to the styrofoam. Also, I didn't have room to store materials so the disposable approach worked well for me.

    peak

  • Sarahsaid
    18 years ago

    Good to hear your voice Peak!?!That is quite a move.Peakpoet Coast To Coast.

  • heehoo
    18 years ago

    Peak the Tufa God---thank goodness you're back. After months of being forced to lie in bed and dream of the things I wanted to do, I attempted a two-layered grot and a casting of a hosta leaf. I did not do this directly on to the patio----remember...I'm the one whose new husband had to use a crowbar to get my first project off the cement. I'm also the (semi)fool who made bowls in the sand and allowed the tides of Puget Sound to set them. They are fine--probably because I did what Tufa God told me to do----used tons of rinse water after taking them off the beach. I've been trying to collect Dena's instructions on casting......Marly's general knowledge---all of which I have printed on scads of paper and stored in notebooks, which are now in a thousand different places. My wonderful husband's face looks pinched and worn as I stumble around and collect "shapes" for tufa production--and he just called from Home Depot, while I scrolled up this page to tell him which kind of tape to bring home. They're going to have to cut off my arms before I give up...but I feel much more secure now that Peak is back.
    By the way, Peak, would it not work to decorate the side of that gorgeous hunk with cement-soaked tulle? What might deter it from sticking?

  • mmfine71
    17 years ago

    Peak,
    Love your ingenuity! My DH calls it craziness, but we know different ;) I just thought I would give you a heads up on a great resource for boxes- Wallyworld layaway dept.! They are more than happy to let you take any and all you want. Other stores have them too. Just thought you might want to save your $15 for more trees.

    Mary

  • justadncr
    16 years ago

    Anyone that has tried this around? Can you add to the thread how it worked out? Thanks

  • sb158
    15 years ago

    New to this forum, but not Gardenweb. Saw somebody making hypertufa on Gardening By The Yard on HGTV, and started reading. This single post answered so many of my questions about ideas I've had...Thanks so much.

  • dragonfly_wings
    15 years ago

    Lots of free cardboard boxes available -

    Try the 'free stuff' section of Craigslist.
    People who have or need boxes for moving purposes
    often list them there.

    Also check your local paper's classifieds.

  • User
    13 years ago

    This is such a great idea and technique, I had to bump it up.

  • delcogardens
    13 years ago

    Excellent post & bump. I wish I had seen this a month or so ago when I started my hypertufa-ing!

  • Linda Karenson
    3 years ago

    Post them on https://boxgiver.com/. I know a lot of people give away theirs on there all the time

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