Finishing a sculpture with reflective glass mosaics is a
great way to make it shine. The glass reflects light beautifully giving the sculpture a whole new dimension.
This instructable is a follow up of my previous “Low-Poly Paper Sculptures” instructable. We will begin this project from the finished paper model. You can also apply the same techniques in the final few steps to apply the finish to any sculpture you have, but I will be creating a mirrored bunny from a low-poly paper model I made. I also recommend using strong card for making the model if you have not already done so.
You will need
Glass mosaic tiles – The smaller the tiles, the better. I used 10mm*10mm*3mm glass mirror tiles I bought on EBay. 2 packs of 500 tiles were just about enough to cover my bunny.
Adhesive – Brands like “Unibond-No more nails” or “Spackling” are great for the job. They usually come in a hard plastic cartridge that you can dispense with a cartridge gun.
2 part polyurethane resin – I bought my resin from “MBFiberglass”. Resin is relatively expensive but it’s worth it. We will use it to strengthen our paper model.
PVA glue – Everyone’s favourite hobby glue!
Tile grout – You can buy this at any hardware store. Try to pick a colour which matches your tiles.
A model to lay the mosaic over – You can make a paper sculpture by following my other tutorial above. You can also use any other model that is strong and rigid (but skip steps 1 and 2).
Some disposable cups, gloves, lollipop sticks and kitchen roll.
Step 1: Preparing the Paper Model for Strengthening
With any glued paper model, the edges where two pieces meet
are never perfect. These need to all be sealed before we continue, otherwise it will get messy. Place small amounts of PVA glue over the gaps and holes in the paper to seal them. It might be worth shining a torch through the model to show any gaps and imperfections you need to fill. The model also needs to have a hole in it big enough to see a good amount of the inside of it. Try to find a place where it will not be seen afterwards and make a cut using scissors. This is where we will pour the resin in and manage it inside the model. I cut a hole in the underside of my rabbit where it rests on the floor so it is not visible.
A little info on resin…
Resin is a wonderful material. It usually consists of a two part fluid which when mixed sets into a strong durable plastic. There are many different types of resin used for all different purposes, finishes, setting times, etc. Resin (like everything) comes in many price ranges each bringing different outcomes. With my personal experience using resin, I would definitely recommend using ‘medium quality’ resin, (usually costing £15 per Kilogram). Buying ‘cheap’ resin is usually a nightmare to handle and produces a terrible finish. Also, expensive ‘high quality’ resin (costing £30 per Kilogram) in most cases bares not much difference to the medium range, unless used for special purposes. For this project and for most projects I use, I buy 2Kg of Polycraft FC-3680. It’s just a resin that I think suits my projects best and is very easy to use. It also doesn’t smell at all compared to other resins which I have had to put up with smelling for months after use; I’m quite happy to let this resin set even in the house.
Step 2: ‘Slushcasting’
This method is usually used to create a final cast from a mould.
I found it works a treat for reinforcing card models efficiently. The art of slushcasting also known as rotocasting or rollcasting is to pour resin into the mould and roll it around until it sets, covering all parts of the mould.
First things first, resin is not very nice to have on your hands and is usually very poisonous to ingest so I would obviously highly recommend not to eat it… and you should be wearing gloves when handling resin at all times to avoid wearing plastic on your hands which doesn’t come off for a week or so. Every resin has its own instructions so read the label on the bottle to find the mixing ratios you need. It may help to pour the ratios into separate containers before mixing them together; they are usually measured by weight so use some scales to find the correct amount. Using polypropylene cups work great for resin, once the resin sets it can be broken out and the cup used again.
For the first layer, mix a total of around 100-200ml of resin into a container; use a lollipop stick to quickly mix the two parts together well. Pour the mixture into your paper model and quickly start rotating your whole model. Try to roll the resin along the inside walls covering as much of them as you can. Aim for an even amount of resin on all walls (try not to let it spill out of your model). Every so often keep checking just in case resin is still dripping through a gap in the paper and clean it up with a paper towel. Once you feel the resin heating up inside and it is no longer runny or dripping, (this could be between 5-10 minutes of you rolling the model) you can leave it to dry. This is your final chance to remove any warping and dents in the model that may have occurred when working with the resin. So use anything you can to prop up/hang/balance your model so that it dries in its completed position. Leave the model to set at room temperature for best results.
The resin should set completely overnight, and the second layer can be added using the same process, but you can use a little more resin. After two coats your model should be plenty hard enough to start applying your glass tiles.
Step 3: Gluing the Tiles to the Model
Now that the model is hard, it’s a good idea to take to the
corners and sharp edges with some sand paper. I didn’t do this on my model and had a few problems with pieces sticking out at odd angles. So very gently sand down sharp edges and heavy angles so they are less prominent, (don’t go too far as the plastic is only a few millimetres thin).
Using the no more nails glue, spread about 1.5mm onto the model. You can use tools and spreaders but I think the easiest way is to spread it with your fingers (unless the you use is superglue which I advise against using) its best to start in a place where you have a large concaved angle, like under a neck or in a mouth as these are the most difficult areas. Apply the small tiles to the fixative and press them into the glue. If you use too much or press too hard the adhesive will spill out from under the tiles and will ruin the aesthetics, we also need to leave enough room down the sides of each tile for grouting, so press lightly and use a small amount of adhesive. Space the tiles between 1 and 4 millimetres apart for a nicer looking model. The tiles tend to look best if they follow some sort of pattern, so keep the tiles in lines as much as possible. This is quite a long process but it will pay off in the end. Understandably, there will be areas which your tiles do not want to fit or will break from the pattern; here it is okay to deviate slightly or to twist a tile at an angle as long as you do not leave too much of a gap between tiles. In my opinion big gaps are what ruin the looks of a mosaic, so try to avoid this. The tops of the ears were the hardest part on my rabbit model to make tiles fit, but as long as you try and tilt the tiles to form as much of a clean ‘curve’ as possible they should look nice, especially when grouted.
As the adhesive is drying you can still tweak areas, rotate and push pieces around. If you gently run your hand over a section of tiles you will notice if any are sticking out at odd angles, and push them back in or flatten them. I would recommend doing small sections at one time so the adhesive does not harden. The adhesive should fully harden in 24 hours and you can now move on to grouting.
Step 4: Grouting
Grouting the tiles is the most fun part of the build.
Grouting fills all the little gaps between the tiles and really gives them a professional finish. When choosing the right grouting to buy, make sure the “width of grout” on the label, matches the spacing of your tiles, and select a colour which suits you (I chose a light grey to match the average colour of the mirrored glass). Note that most grouting dries a lighter colour than when it is being applied.
Before you start grouting, make sure any last bits of glue are removed from the surface of the tile, and any loose pieces are permanently fixed in place. You can use a damp cloth to clean the surfaces of the tiles and remove glue from the gaps. Depending on which type of grouting you buy, they will have different mixing ratios of water to powder. Mine were measured by weight so I used a scale and an empty plastic pot to mix in. I found when working with smaller gaps and tiles, it’s actually easier to mix less water and have a more viscous grout to work with.
Using your fingers, grab some grouting and push it into all the gaps between the tiles, do not worry about getting it on the front face of the tiles now because we will clean it later. Make sure you push a good amount into the gaps and smear it from tile to tile filling gaps between them. When an area of tiles has been filled with grout, use a cloth or a clean hand to wipe over the tiles. Doing so will remove the excess grouting from the front face. When you wipe the front of the tiles you will notice the grouting remains in the gaps between them; try and leave enough grout in these gaps so they bow slightly below the face of the tiles. A good way to ensure the perfect amount is to run your finger from a low tile, to a tile sitting slightly higher, this will remove just enough to leave a perfect grout.
It’s best to work with small areas of the model at a time to ensure the grouting won’t harden on the surface of the tiles. Make sure all the visible faces of the tiles are wiped clean from grouting before it is left to set because it’s a nightmare to remove afterwards. Leave your model to dry at room temperature for 24 hours and the grouting will have set. Now all you need to do is give it a wipe down with a wet cloth and it is done!
Thank you for reading this instructable, I hope this project is as enjoyable for you as it was for me.