Introduction: Makng a Concrete Gecko (7.5m )

Picture of Makng a Concrete Gecko (7.5m )

I was commissioned to produce a concrete model of a gecko for a new housing development.

I am a sculptor,working in wood, steel , bronze , plastics and concrete.

For this project, I did quite a bit of research into high strength mortar mixes ( no stone , just sand / cement )

Step 1: GECKO Underwoodisaurus Milii

Picture of  GECKO Underwoodisaurus Milii

First , catch a gecko. This fellow helped out for a bit. Then I made a maquette...

Step 2: Maquette

Picture of Maquette

Carved in foam and coated in acrylic plaster and finishing cloth ( fine chopped strand mat )

Step 3:

Picture of

sketching with 10 mm steel rod

Step 4: New Studio

Picture of New Studio

Using a ring roller, building the body, welding intersections

Step 5: Sub Frame

Picture of Sub Frame

Heavier steel for strength and to bond to slab.

Step 6: Internal Skin / Hessian /poly Foam Internal

Picture of Internal Skin / Hessian /poly Foam Internal

I glued hessian to the inside of each half of the steel work. This was to provide a surface that could accept an internal spray-up of polyurethane foam.The purpose of this was to provide a firm surface to apply the glass and steel fibre reinforced mortar on the outside , through the layers of bird mesh.

Step 7: Reassembling the Two Halves and Chicken Wire Mesh Application

Picture of Reassembling the Two Halves and Chicken Wire Mesh Application

Chicken wire was stitched on to the steel rod armature. Cast concrete eyeballs fitted.

Step 8: Mortaring the 25 Mm Skin

Picture of Mortaring the 25 Mm Skin

The mortar mix was designed in consultation with a concrete engineer from Tasmania.

3 parts sand

1part Portland cement

10% Magnesium Oxide ( high early strength )

Fly ash

steel fibre reinforcing

glass fibre reinforcing

water reducing compound ( the strength of concrete is inversely proportional to the amount of water added or water-cement (w/c) ratio.

Step 9: After Curing, Acid Staining and Anti Graffiti Coating

Picture of After Curing, Acid Staining and Anti Graffiti Coating

I made 6 gum nuts in ferrocement also , to provide scale and to be used as casual seating.

Acid stain in various colours was worked into the surface and finally a coat of anti graf sealer that came from a firm called Gecko Coatings. It seemed appropriate...

Step 10: Leaving the Studio

Picture of Leaving the Studio

Big test ! the gecko, weighing approx. one ton ( 1000kg ) was lifted out of the studio and trucked to its place in a playground. No cracking. The sub frame was anchored to the ground slab and a coating of rubber soft fall was put around .


Andy Jarman (author)2016-05-29

Al I'm in Perth WA. I'm looking for someone to help build a family of giant long neck tortoises. Contact me if you are interested

Delhia (author)2015-07-27

You are amazing! Thank you for such beautiful photos start to finish!

HGC (author)2015-03-09

he or she is beautiful, thanks for sharing. Do you have a link for seeing any of your other work?

ryks (author)2014-08-16

nice job for the kids ............thank you for sharing

Robibame (author)2014-08-15

very nicely done. too cool.

mousebear (author)2014-08-13

thats so super cool it almost looks real

TrollFaceTheMan (author)2014-08-04

Very cool!

poofrabbit (author)2014-08-01

Congratulations on being a finalist in the Concrete and
casting contest! Best of luck to you! I am in love with this sculpture, just plain lovely.

Cheryl.Storm4 (author)2014-07-28

That is so adorable !!! I have a leopard gecko and he looks a lot like the one you made ! I want the smaller test piece you made !!!!!!! sigh

chloe.stamper (author)2014-07-28

Beautiful work!

mastersoncraft (author)2014-07-27

Wow the scale of this project is impressive. And the results are fantastic. I bet this takes the prize for the worlds heaviest gecko.

You should set up an x-ray machine so people can see your beautiful steel work.

nlangla (author)2014-07-21

i had seen your beautiful gecko via the tec eco website-i notice that you don't include clinoptilolite in the mix? i am still trying to understand the chemistry involved and not quite sure what part the clinoptilolite plays but i thought you had used that in the mix? Also what was the proportion of the flyash, please? i have been doing some 'experimental' concrete work-mostly sculptural - magnesium phosphate concrete is an area of interest! Thankyou for sharing your construction method- especially the inner 'sleeve'- i wouldn't have thought of that.. Excellent work, very gecko!

shaperAl (author)nlangla2014-07-21

nlanga, thanks for your post. I have lost all my notes on the mix ratios, so what I put up was from an imperfect memory of it. Yes the clinoptilolite was an ingredient, but a small percentage. With the additives it was a very "short mix", so the internal foam allowed lots of pressure and vibration to compact the layup.

Earlsart (author)2014-07-21

Great job, Al. The proportions are perfect. I use a similar technique to make Living Tree Art with internal programmable plumbing systems, different type of concrete. Lots can be done with concrete. Never heard of Hessian. Looking that one up right now! Thnx!

daxxvondrachen (author)2014-07-19

Great story for gecko to tell his buddies...."I was abducted by a huge alien, picked up examined thoroughly and strange flashes of light (pictures with flash),,,,I was released but when I went back a few days later to figure out what happened ,,,,there was this huge statue of me!!! Then it came to me,,,,they think I am a god!!!!!"

Tarun Upadhyaya (author)2014-07-18

This is so amazing :)

What happen to the gecko you caught?

I did not read "no animals were harmed in the making of this" :D

shaperAl (author)Tarun Upadhyaya2014-07-19

no animals were harmed in the making of this. he was released back into the wild (my backyard )

Tarun Upadhyaya (author)shaperAl2014-07-19


exius (author)2014-07-18


studleylee (author)2014-07-18

Amazing!!!!! Well done and explained!!!

CliftonSears (author)2014-07-18

Impressive. Very well done.

tseay (author)2014-07-17

Truly inspirational.

xenobiologista (author)2014-07-17

This is awesome. It reminds me of the concrete dinosaurs in the park in Taiping (Perak, Malaysia). I thought they were the coolest things when I was a little kid.

jugglebird (author)2014-07-17

Would it be possible to provide a ratio formula for the concrete that includes ratios for the items that you mention but that don't have proportions?

Great sculpture!

MiriamS (author)2014-07-17

That's a beautiful Gecko :) Great job, thanks for sharing all the details - I've often wondered what materials and processes are used to make a very large scale sculpture.

ysabet (author)2014-07-17

This is marvelous! I live in Tucson, Arizona in the U.S.A., and this town has a ton of street, park and roadside art; your gecko would fit in beautifully (we also have a lot of geckos, though they look a bit different than the one you show.) Around here the prevailing theme is Diamondback rattlesnakes-- there's a snake bridge, a team named the Diamondbacks at the University of AZ, snake median art built of concrete and tiles, etc. Like I said, your gecko'd fit right in!

spylock (author)2014-07-17

A little more than a weekend project,but a great piece of art for sure.

houndog2g (author)2014-07-17

That is great!! I don't think I'm quite that crafty though!!

spark master (author)2014-07-17

nice gecco, ok everyone think Halloween.......but change to crocks, gators and ghosts!

UniKitty75 (author)2014-07-15

I wish I could make that but I'm only 10 years old

spark master (author)UniKitty752014-07-17

make a small one say a foot or two long

good luck

this was a very awesome thingie indeed.

the gecco stops here!

thebluebulk (author)2014-07-17

THATS WILD! great job

ardrhi (author)2014-07-17

That's an interesting 'ible. The method might be useful, but I can't foresee myself making a concrete gecko.

"Brought to you by Geico."

ttowngirl (author)2014-07-16

How long does it take to make this? Do you have to wait for the concrete to cure? Was this made in what country? I love the texture of the gecko; was that made by the chicken wire?

shaperAl (author)ttowngirl2014-07-16

I am in Perth , Western Australia

ttowngirl (author)2014-07-16

How long does it take to make this? Do you have to wait for the concrete to cure? Was this made in what country? I love the texture of the gecko; was that made by the chicken wire?

shaperAl (author)ttowngirl2014-07-16

It took 2 months. Most of the time was spent on the steel work.The concrete cured for 28 days before the acid stain and sealer were applied
The texture came from a polyurethane texture pad that I cast off a plaster mould from a clay slab that I had pushed a marble into.
you have to get your head around positive / negative / material changes. A bit like printmaking.

anguspodgorney (author)2014-07-15

Nice indeed! I think I'm going to give a smaller version a try!

Gregbot (author)2014-07-15


Mielameri (author)2014-07-15

So cool!

cazpian (author)2014-07-15


FlipLucky (author)2014-07-15

That looks totally amazing.

TC78 (author)2014-07-15

Amazing work, so beautiful. . You can be proud of yourself, that's for sure. .

chrisjhill (author)2014-07-15

Amazing! Geckos are such a cool animal, I'd be tempted to buy one of these for myself.

samalert (author)2014-07-15

This looks so awesome and real. It was fantastic !

jessyratfink (author)2014-07-15

Absolutely amazing work! It's beautiful. :D

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