Making a Mosaic Trivet, Part IV: Grouting mosaics

DSCN4804Making a mosaic trivet, Part IV: Grouting and finishing.

Now it’s time to get down and get dirty. Roll those sleeves up, tie on your pinny and get out the rubber gloves – the moment has come  to grout your mosaic.

NB: If you use porous stone as your mosaic material, then you need to apply a layer of varnish on the finished work BEFORE grouting to protect the stone and stop it ending up with a horrid grey film.

You’d be surprised how many people are not sure what grouting mosaics means, so just in case one of those people is you: grouting is when you fill in the gaps between the mosaic tiles to strengthen and protect the work. It also has the effect of bringing the piece together as a co-ordinated whole. It’s the most common method of finishing off a mosaic – but not the only one.

There are three ways of finishing mosaics:

1. Grouting the mosaic using tile grout – the same sort of grout as you’d buy to grout your bathroom or kitchen tiles. This lovely little thing from Scarab Glass Works shows very clearly what I mean – the grout is the grey bits. Scarab glass works. 2. ‘Self -grouting’ : many mosaics are made by pressing the tesserae down into a soft adhesive which squishes up around the sides of the pieces and holds them down. The famous Byzantine mosaics are made in this way: Neonian Baptistery, Ravenna, Italy.3. Not grouting at all. The mosaic pieces will be firmly bonded to their substrate and if they are also placed close together, some people feel that grouting is superfluous. This piece from Jacqueline Iskander looks non-grouted: Jacqueline Iskander Mosaic Art

Before you start, you will need to make sure you have a way of getting rid of your excess grout – its nasty stuff, blocks drains and is generally yucky so you can either:

  • Find a corner at the back of the garden (in the long grass, behind a tree) to swill out the used containers and rinse off your tools or
  • Be ready to use lots of scrunched up newspaper and paper towels to give your tools and containers a thoroughly good clean after use.

I have a friend who once proudly told me she dealt with the problem by taking her grouting bowls out into the street and sluicing them off into the public drains…..Errr, no, that doesn’t work either. Any drain is a drain and the whole thing about grout – even watered down grout – is that it hardens and becomes as solid as concrete.

Right, we’ve got that clear, so the next thing you will need to do is to:

Prepare your tools and supplies

For this you will need:

1. Rubber gloves.

2. Plastic sheets to protect your surfaces/the floor under where you are working.

3. Two deep plastic bowls or buckets. Old ice cream containers will work just fine.

4. A spreading tool. An old plastic loyalty card is ideal for a mosaic this size or you can buy spreading tools at any hardware shop.

5. Two good, thick sponges.

6. Grout. I use Isomat Multifill Smalto 1-8mm, which means that it will fill joints up to 8mm wide. I also tend to use grey – not light grey, or cement grey or any other kind of grey. But just grey. I could write a whole separate post about grout colours but, for now, let’s keep it simple.

7. A spoon or implement of some sort to mix the grout.

8. A bottle/jug of water. I also find it handy to have one of those water spritz things which are used for spraying plants so that you can fine tune the amount of water you add.

9. Stiff plastic, scrubbing brush for cleaning.

Method:

1. Put your gloves on and make the grout according to the packet instructions in one of your plastic tubs. For a project of this size, you will need roughly two yoghurt pots of grout powder as I tend to ere on the generous side. Add the water in dips and daps and keep mixing until you get the right consistency – you are aiming for a paste: not runny, not with water sitting on the top, and not too firm. I read once that the best consistency is that of a cow pat and I regret to say that that is the analogy I always use.

Mix the grout according to the instructions.

2. With a sinking heart (it’s never easy), put a big dollop of this horrid, dark, goopy stuff on the front of your beautiful mosaic and use the spreading tool to push the grout into the gaps.

Apply the grout to the mosaic with a spreader tool.

3. Cover the whole mosaic with the grout and don’t forget the edges:

Don't forget to grout the edges.

4. Use your fingers to push the grout into all the gaps. You will find little air bubbles appearing as you apply the grout, so keep going until all the holes are filled.

Use your fingers or the spreader to push the grout into the gaps between the tesserae.

5. Now use the spreader to remove the excess grout.

Remove the excess grout.

6. Fill your second plastic tub with clean water.  Soak both of the sponges and squeeze out every last drop so the sponge is damp but not wet.

Take a sponge, wet it, and then squeeze out the excess water.

7. Wipe the front of the mosaic with the sponge – once – and then turn the sponge and using a clean side, wipe the mosaic again. It’s vital to always use a clean side of the sponge as otherwise you are just smearing grout residue over the cleaned parts of your work.

Use a clean side of the sponge to wipe off the grout.

8. Keep going with both sponges, frequently rinsing them out and using fresh water until the front of the mosaic is clean. It will still look slightly on the grungy side, but don’t worry, that will come off in the final clean.

Making a mosaic trivet: in photos

9. Leave to dry for a good, long while. There is no rush so better to leave it for more time rather than less. Once it’s thoroughly dry, get a stiff plastic brush, clean water, and give it a good, energetic wash.

Scrubbing the mosaic to remove grout residue.

 10. Put four, little, felt self-adhesive  patches (the ones hardware shops sell to put on chair legs) on the back of the mosaic so it can be put on a polished wood surface without scratching it.

DSCN4831

Drum roll….Der, der! You’re done. Congratulations.

Keep tuned for the next mosaic project: making a mosaic on mesh.

 

Related posts:

5 Comments

  1. Hi,
    I am from Bangalore, India. I dont find any classes where I stay for mosaics. its very people do it here. atleast i dont find anyone teaching when i looked up on internet.
    i have collected scrap glasses, vitrified left over tiles, and terracotta tile in an attempt to make mosaic art.
    glass failed as i have hard time figuring out using a diamond tip cutter and making precise cuts. breaking randomly is an option but however i would have been happy if i could have done how i wanted to.
    i had a bit of issue to cut vitrified tile but soaking in water and then making a score line to cut did help in some way.
    your site has helped me to learn given than i dont have classes.

    my question.. you have mentioned to apply varnish on porous/unglazed kind of tesserae. since varnish would be runny and may settle in between the tesserae wouldnt it prevent grout applied later to adhere and not bond?

    What are some materials that can be used if grout not used. would using silicone sealant/caulk be sufficient?

    Nagashree

    1. Hi Ngaashree, Good to hear from you! The varnish I use is thick (ish) and not all runny so I don’t have the problem of it settling in between the tesserae. It’s a special varnish for stone – do you have anything like that over there in India.
      A lot of mosaic artists don’t grout their work so you don’t have to if you don’t want to. They press the tesserae directly into a concrete based mixture (like tile adhesive) so that the mixture comes up between the tesserae and self grouts.
      If you haven’t already, then I’d really recommend that you join the Contemporary Mosaic Artists website http://mosaicsandceramics.ning.com/ as they have lots of practical information and forums and groups that you can join and share information and get advice. It’s really, really useful.
      All the best, Helen.

Leave a Reply

Your email address will not be published. Required fields are marked *