As we have opted to do our main bench (or counter) tops in concrete ourselves due to cost, we have a fair amount of testing and learning to do…
Our main kitchen countertop area is well over 8m2 so traditional concrete was out of the question due to the weight.
We have opted for GFRC (Glass Fibre Reinforced Concrete) for it’s many benefits. This post if an overview of GFRC and some tests including a bench – the process for the bench top will be in another post.
Instead of aggregate and steel mesh, a special mix that includes alkali resistant glass fibres is used, making it stronger, lighter, thinner, more flexible, more crack resistant and more impervious to staining and chipping.
After reading copious amounts of literature and watching videos on other people’s attempts, mistakes and training – there was nothing left other than to buy some materials and tools and get into it…
We sell a variety of tools (www.bonzabuy.com.au) so we used a number of items off the shelf and opened a few new accounts with people who supplied / manufactured other tools or materials needed.
We sectioned off half of the lounge room with black plastic – on the floor and up to the roof to keep dust and mess contained as much as possible. 44 barrel drums we used with forms across as benches. Compressors, mixing drills, trowels, scales (for measuring the ingredients) – a mini workshop!
We are blown away how God has made all this possible – and reminded of just how much He changes things: Some of the scales were from measuring drugs – redeemed for a good purpose! Tools we had bought on special to sell (and hadn’t) now were exactly what we need. A ‘chance’ encounter buying a second hand mixer at a bargain price leading to an inside contact for materials and additives that seem superior for GFRC. Strange ways of provision to enable us to buy the ingredients. Left over steel. The list is incredible – thank You Jesus!
Some of the tools:
Custom sprayer for backer coats and Ox Sprayer for face coat
A Measuring Bench was set up with scoops, measures, and many different weighing scales to measure accurately the additives for the mix.
We made up some block squares out of left over form wood from the Rammed Earth and some aluminium trim from the windows:
Our first spray up was to test the process and colour options to start to get an idea of what type of grey was suitable for the kitchen:
Amazing how strong this stuff is!
Inside a test brick that we hammered until it broke to see the strength – the backer coat with fibres and the top coloured face coat…
Then we polished the blocks up in different ways and used different sealers to see the differing results:
Then a larger test slab test which came up beautifully with some polishing:
Next, we wanted to try a larger section to test the process whee the job and mixing would be closer to the kitchen. We decided to do a slab that could be used as a desk in the office.
We designed it big enough for 3 computers, with holes for the power cables etc.
Form ply was used as the base, with aluminium channel for the side forms and 50mm plumbing pipe for the cable knockouts.
Form release was used on the form ply, then the concrete sprayed on in layers with 3 layers of glass ‘scrim’ (reinforcing for GFRC – like red mesh but made from alkaline resistant glass fibres) and allowed to dry.
We then tipped the concrete out after 2 days of drying and started to polish. Heavy – good thing the boys are strong!
Test polishing the desk with a wet grinder…
Then hand finishing – a family affair!
Lastly we sealed with a specialist bench sealer (we are testing a few different ones).
Next, we used some left over steel to weld up a basic frame that was strong and had a footrest:
And painted with another product we sell that we have been amazed at (Galmet Hammer Finish range).
Then of course we hd to test the strength…highly technical!
With a couple of old computers we got for a song from all around the place (more miracles!) and it’s ready for work!:
We aren’t very happy with the edge faces – so we have adjusted the technique and mix for these face coats and will see how this goes next time.
That said, it still looks amazing and is a huge difference to the plastic fold up table we have been using!
A couple of days later, we started to test a new technique with a different surface effects. Instead of wasting the concrete, we designed it to suit a shelf above the computer desk.
The effect of the two different techniques together was amazing: (white spots and black splatters on a mid-dark grey base)
The finished shelves in place with some bottles, cups, lunchboxes, toothbrushes, chocolate, chais and teas that we sell (safewaterbottles.com.au/buy or www.bonzabuy.com.au) – as well as the custom aluminium sculpture things that the kids made (which I love!).
Not bad for a test piece! Although the process is different, we feel confident enough to make a start on the Laundry benches as a pre-test for the main kitchen benches.
Can’t wait!
We are very thankful that God has enabled us to live this life-style and we have the resources to be able to trial these skills.