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Grow a square watermelon

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This is really, really easy to do. (Note: you may be able to use this technique to grow other stuff in the form of a square ( actually in the form of a cube) and apply the general idea to other shapes.)

 
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Step 1: Materials and tools

Picture of Materials and tools
You need 6, 8" square, 3/8" thick (or thicker) sheets of polycarbonate plastic. (Lexan)

You will need 4 gate hinges and 2 hinged clasps with flat head machine screws and hex nuts plus at least 8 or more 1" to 1-1/2" long, thin wood screws and possibly a 36" length of angle iron or aluminum angle (cut to 8" lengths to yield four pieces) if you have thinner polycarbonate, a power drill and hole saw, and a hand saw or power saw such as a jig saw.

Step 4: Trim the inset sides

Picture of Trim the inset sides
Measure the width of the sheets and trim each side of the the inset sides by this width.

Step 5: Fasten sides

Picture of Fasten sides
The edges of the inset sides will have to be trimmed the thickness of the poly you use so they can be inset and still keep the box square. Trimming these edges is probably the hardest step.

Drill pilot holes through edge of the left and right sheets into side sheets between them to accept the wood screws. Use 2 or more screws per joined edge. A piece of angle iron or aluminum can be used to beef up the corners if the polycarbonate you have is too thin. (If the poly is too thin, however, it may bulge.)
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For those of you lacking either the time or tools to complete this task, we offer a commercial box mold specifically for molding watermelon at MelonMold.com. We're inexpensive and ship internationally from the US.

melonmold.com

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wstringham29 days ago

what are the overall dimensions of the box, please respond soon

The actual size of the melon your mold will produce
is 7.5” at its tallest point and 7.5” at its widest. It is 7.5” at its
deepest point.

melonmold.com

box1a.jpg
Does the Box have to clear and made out of plastic?
it is better be clear cos the fruits need sun to grow to look better , and plastic seems to be the best choice we have by now ..
IMG_1198.JPGIMG_3667.JPG

I read the other day about a japanese guy who managed to make a hearts shaped watermelon 'after many years of research'. Then I already knew it was bogus as it is just a matter of the right mould and here I see those are available already.

https://www.youtube.com/watch?v=5tydgE3RQxg

fashboy6 months ago

'This is really, really easy to do.' OMFG SO EASY

fruitmouldcom8 months ago
i have tried this method ,but seems not easy .....we have grown some like the below one :

Suppliers for plastic square box mould for square watermelon.jpg
fruitmouldcom8 months ago
it is great job to make this square watermelon box ,but very time consuming ...
why don't you just come and buy one very easy ,it just cost you like $10 , will save you a lot of energy .for anyone interested , come to www.fruitmould.com
IMG_3667.JPGheart-shape-watermelon-molds.JPGsquare-watermelon-box.JPG
fruitmouldcom8 months ago
oh ,by the way , i have a client grown a lot of square shape watermelons , he got many experience on this ..check the photo
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kcls4 years ago
I can see it now- instead of a watermelon, grow a pumpkin in a cube shape. Then, carve a Domo-Kun face on it. Voila! Domo-Kun Jack-O-Lantern.


I've got dibs on the 'ible.
huh ... seems many guys are really interested in the pumpkin .....why don't we just make a mold for the pumpkin ,but what shape you want it to be ??
omnibot kcls4 years ago
Do it!
kcls omnibot4 years ago
Gotta wait until I have a garden to grow it in! Living on a boat and all, I don't have a very big yard :D
you don't need a garden i grew a pumpkin in a large pot and trained the vine to a railing. when fruit formed i used pantyhose to support the weight.
you do, it's just REALLY flooded
So... rice?
aseaheru xenor3 years ago
salt water.......o_0
exactly
put it on the mast head. o_0
Hiroak kcls4 years ago
I'm on a boat Motherfu Ha ha very orginal I know I lived on a boat, the sail type for 2 years and build floating garden boxes out of blue foam board. I had a slip larger than my boat so I just attached them to the dock. Then I got a bigger boat and build two above ground planter boxes on the deck. I even tried to grow an orange tree, to combat the scurvy but I live in Alaska.
i bet you don't need all the hardware. you can probably use big rubber bands to hold the form in place.
good request , but you are really underestimate the growing stress from watermelon , it is a big guy :-)
Would a box work? I do not have the ability to make your cool invention
if your box is strong enough ,then it should work ,yes, to make one mold is really practical skill...
elkrivermr1 year ago
how do you deal with rain and condensation?
rain will not affect the growing ,because even with some rain store inside of the molds ,it will be gone soon by the sun shinning ,isn't it ?
sinnae10 months ago
I feel like this would introduce a ton of moisture-induced rot unless plenty of ventilation is drilled into each panel.
yes , you are right , it has 4 holes on the size wall of the molds to keep ventilation ,the sun shinning might be really strong , you need to cover the black net at the beginning ...
Not4Guy10 months ago
I wonder if this could be doing to shape a pumpkin into a skull for witches hat?
this polycarbonate plastic made square mold can be used on pumpkin ,but it is really hard to say if can success , depends on the mold thickness and the pumpkin stress ,ours are 3mm thickness ,should be strong enough for pumpkin , go www.fruitmould.com , check more shaped fruits ,you will be amazed for sure ...
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fruitmouldcom8 months ago
OH, this polycarbonate plastic made square mold looks good ,but we also have another injection made square mold for watermelon which is well tested in past few years,check www.fruitmould.com , you will find more amazing shaped fruits ...great fun :-)
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Nukeman2 years ago
The Lexan to build this costs about $80. Will plywood work?
myakka2 years ago
How about triangular( pyramid) shaped ones. Or dodecahedrons!
myakka myakka2 years ago
Or how about make the entire alphabet
kjohnson402 years ago
we grew a square honeydew (by accident) it was in a cement block we used to "fence" the garden with.
jameseyboy2 years ago
HELP barbies on the bbq
tinker2343 years ago
wow i love this
moonchylde3 years ago
I wonder if this would work with tomatoes, or if the boxes would be too heavy for the vine to support. Another thought I had was two-liter pop bottles (watermelons with feet; they'd also be good for watermelon spikes :P), though I'm not sure if the fruit wouldn't split the plastic. I might experiment with this.
geoslim133 years ago
to quote Eurotrip "Gotta love that exchange rate!"
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