In this edition of Troubleshooting Pours, we’re going to talk about an issue that is very easy to correct: bare spots!
What are bare spots?
Bare spots are pretty easy to recognize; they are areas in your painting where the surface you’ve poured on shows through. This results in an uneven painting with an uneven surface texture.
What causes bare spots?
There are a few different things that can cause bare spots, and fortunately, all of them are relatively controllable.
If you use dimethicone, silicone or other additives in your pours to get cells, you’re probably aware that mixing these additives in your paint mixture does carry some inherent complications.
One of these complications can be improper mixing. If you do not fully mix your additives with your paint and medium, bare spots can occur as a result of extra, unincorporated additives coating the surface that you’re working on and repelling the paint from that specific area. This is why it’s very important to make sure that you’re mixing your paint, medium, and any additives you’re using completely, and that you’re using the proper amounts of each.
Speaking of amounts, if you use too much of any of your additives, including medium, you’re likely to get bare spots in your finished painting. Ratios matter! It can be tempting to add more silicone if you’re not getting the cells you want, but adding too much isn’t going to get you favorable results!
If you’re re-pouring a painting or trying to create depth on an already finished painting, you may run into a challenge if you’ll sealed the painting with an especially glossy sealant like Polycrylic or resin. It can sometimes be hard for paint to stick to these surfaces, and especially if you’re using an additive for cells.
To successfully paint over a glossy surface, it’s a good idea to either lightly sand the area or prep it with a non-glossy acrylic paint first, with no additives. Even if you’re just trying to create depth and paint a smaller portion of your painting, you can “spot prep” the areas you’re looking to paint to make sure that the paint mixture sticks. And of course, the previous additive rules apply: make sure your mix is completely incorporated and that you haven’t used too much.
Another cause of bare spots is too much water. Water alone as a medium can break down the binders in acrylic paint, which will cause separation. Separation will result in clumps of paint and bare spots.
To avoid this, use water sparingly as a medium. That’s not to say that you can’t use water at all, but it’s a good idea to use another medium as well. For example, you can mix Liquitex Basics with Floetrol and water if you want to stretch out the value of your medium. Do keep in mind though that the benefits of using a professional medium when you’re selling or displaying your work are well worth the investment.
Another cause of the dreaded bare spots is the use of heat on your piece. If you use a torch to coax cells out of your paint, be very careful not to hold the torch too close or you may overheat the paint and cause it to separate. When torching a piece you should be holding the torch at least six to eight inches away to avoid scalding the paint. If you see smoke coming from your paint, you’ve gotten too close, and definitely if you see sparks!
The last cause for bare spots that we’ll explore today is using high pressure air to manipulate your paint. If you choose to use canned air or an air compressor, be mindful of how close you hold the nozzle of either to your paint. Not only will you end up with a beautiful Jackson Pollock-style abstract painting all over your wall and work area, but you’ll also end up with a bare spot on your canvas. The same issue can arise with using a straw but with an added “bonus”…saliva. Saliva can also cause bare spots on your canvas, so try not to blow too much saliva through the straw.
In both cases, the distance between what you’re pushing air through and the canvas is key. It’s better to start blowing too far away and move your way towards the canvas to find the sweet spot rather than starting too close and blowing your paint all over the place!
How to Fix Bare Spots
So, you’ve already got bare spots. What do you do now? First of all, you don’t need to scrap the painting.
Similar to crazing, you can “patch” the bare spots with paint, glitter or gold flakes. Alternatively, if you’re just not happy with the unevenness, you can sand down the paint and repour over it. Sealing with a flood coat of resin will also even out your surface, but make sure that you’ve removed any excess silicone, dimethicone or other additives from the surface before pouring your resin, or you’ll get bare spots in that, too.
Bare spots are frustrating, but completely and totally avoidable with small tweaks to your mixture and process. Be mindful of your ratios, mix completely and you’ll have fully covered pieces that you’ll love.