Hypertufa Face Pots or Grots
Introduction: Hypertufa Face Pots or Grots
Hypertufa Face pots or
Grots
First here is a definition of Hypertufa.
Hypertufa
From Wikipedia, the free encyclopedia
Hypertufa is an anthropic rock made from various aggregates bonded together using Portland cement.
Hypertufa is intended as a manufactured substitute for natural tufa, which is a slowly precipitated limestone rock; being very porous, it is favorable for plant growth. Hypertufa is popular for making garden ornaments, pots and land forms. Hypertufa is relatively light compared with terracotta or traditional concrete and can withstand harsh winters, at least down to -30 °C (-22 °F).
In this Instructable we are going to learn how to make a face pot or Grots.Back in the early days of the internet, there where various garden groups with hypertufa artists trading info. The face pots where given the name grots , short for grotesques which was a name given to gargoyles.
Supplies
Portland cement type 2, peat moss, bag of sand, gloves. Plastic buckets and pot.Modeling tool and dowel rod.
Step 1: Mixing the Hypertufa
Supplies
Portland cement type 2, peat moss, bag of sand,gloves. I prefer play sand but a medium sand will probably be stronger. I've been making tufa for over 25years,anything from pots to large sculptures .There are many different recipes out there but this is the one I always used. There are many that call for vermiculite and perlite which is fine but the sand gives it strength, although it also adds weight.
The formula is 1 part cement ,1 part sand and 1 part peat moss. For larger sculpture you can add acrylic admix , nylon fibers for extra strength and mesh and rebar frames .
I use a variety of cans to measure .I also write down what I use for future reference. For example 1 coffee can (1 each of materials) = 1 small mushroom and base.I first mix the sand and peat moss together, picking out thepieces of stems and twigs out of the moss. Then I mix in the cement. It probably helps to wear a mask. Then make a wellin the middle and add the water . Be careful not to add to much. Add some and mix and then add some more till youget the right consistency. 389
You do not want it to wet !! Just enough so when you squeeze a handful it will hold its shape. The wetter it is the weaker it will be.
Step 2: Making the Pot
Making the pot
To make the pot I'm using a 9” x 8 “ bucket and line it with a plastic bag , this adds texture to the pot and helps remove it from the bucket. I also use black plastic flower pot to place on the inside so the walls are about 1 to 2 inches thick.I then take a handful and press it into the bottom, about an inch thick. At this time I also put a hole in the middle with my finger.
Then using a handful at a time, I start going around the mold pressing the tufa together,using my thumb to press down on the edges. I build this up a couple of inches to get the sides started.
Then I place one of the black pots on the inside making sure it's even all the why around. I then start adding a handfuls of hypertufa around the pot a inch or two a a time and tamp it down with a piece of wood.Then I run my fingers around the top and smooth it out. Then remove the pot from the center and fold the plastic bag over into the inside.and let it sit for 12- 20 hours or till it's firm enough to handle. But be careful it's still fragile.
Step 3: Making TheFace
Making the face
Now I mix a a batch of tufa normally a half a coffee can of sand , Portland cement and peat moss. I first paint on some acrylic admix to the pot just because I have some. I've made these for years without it. I also make this a little wetter the the pot mix. Wearing latex gloves I take a handful and start at the top and press it on and rub it in .It does fall of now and then. After I'm done with the forehead I do the nose ,then the eyes ,lips and finally the cheeks. I use a clay modeling tool for all the modeling and a piece dowel rod to add the pupils to the eyes.
Then I wrap it up in the plastic bag and let it sit for at least week to cure. This is the minimum. The longer the better. 556