Tuesday, January 4, 2011
Mediums and Other Paint Additives
Well...not that kind of medium, but close. If you want to stick to the analogy you can imagine that medium is what bridges the gap between your GW paint pot and your model.
In this post I'm going to go over some of the different types of mediums and additives that you can find by the liquitex company. Any of these can be purchased at a craft store such as Hobby Lobby or Micheal's. If you're unable to get to one of those then you can order online from one of the largest arts suppliers, Dick Blick.
Matte Medium is the staple of your mediums. If you buy one medium, this is your guy. When it comes to GW paints, they're thick. Super thick; Lexington Steele thick. You can dilute it with this stuff by 2 parts and still get good coverage. That means you can essentially run a 2 for 1 sale on GW pots when you combine them with this.
When you thin your paint with just water it breaks it up and causes the body to fall apart sooner. I wrote an article a while back about what that means but basically, it's like the pigments coagulate and your paint turns microscopically grainy.
When your body falls apart it doesn't effect the solid coating very much but when you're trying to do multiple thin layers or airbrush it will matter and end up really looking terrible.
When you are doing thin layers you really want to thin it with this stuff because if you just thin it with water it'll end up turning into a wash. Instead, if you use the medium, it'll hold together but be like a very thin filter color. When people do light sourcing and get that illuminated look, they've thinned the paints down with matte medium to make their semi-opaque paints.
The other must have for painting is flow aid. The design of this is to break up surface tension. Surface tension, for those of you more than 10 years out of high school is what causes water to "bead up. It causes water to basically want to be in a ball, like when you see the space videos of astronauts sucking down floating balls of tang. Greater surface tension means the fluid wants to be a sphere; Less surface tension means the fluid just splashes out were ever it wants to be.
Paint has a greater surface tension than water so when you brush on your paint, all that medium and pigments prevents it from setting smooth and that's why you get brush strokes. Flow aid, on a basic level, prevents brush strokes.
An important thing to know about flow aid is that unlike other mediums and additives, its in a concentrated form. You'll need to read the instructions on your own bottle but it's usually a 1:10 or 1:20 mixed with water. To help you guys that failed math, that means if you have a gallon of Flow Aid, that means you need to mix that in with 10 gallons of water, making a total of 11 gallons. This means, your 8 ounce bottle of Flow Aid will mix with 80 ounces of water to make 88 ounces of flow aid ready to mix. Flow Aid should last you forever...unless you're a commission painter....
Gess0 (pronounced Jesso)
Gesso is a primer used to prep canvas for acrylic painters. It works also with GW models. They make Gesso in black, white, and clear. Gesso can be brushed on in the most aggressive of fashions. If you youtube something about Gesso priming you'll eventually find videos of people just globing this shit on and it drying thin without obscuring any detail.
Clear Gesso can be mixed with any color to make a color primer. I haven't done this yet just because I still have a ton of black and white left. Where I'd start with experimenting with this is by mixing a fresh, unadulterated pot of GW paint 4:1 and work forward or backward on the ration from there.
As for using Gesso as primer I swing back and forth daily. I love it, I hate it. I think the happy middle ground I'm going to find for this is to use it for touching up scratches or mixed areas when I use a can spray.
The problem I come across with this is that it doesn't hold nearly as well as can primer. I've peeled this stuff off models with painters tape. It helps when you mix it with matte medium to give it a little more holding power but it'll still scratch off. Another tip to make it work better is to really do a good job cleaning your models.
The positives are that its cheap, lasts forever and can be sprayed out of an airbrush. Also, its not sensitive to the environment (humidity, temp, ect.) as the can primer is.
Slow Dry (or Fluid Retarder)
Slow dry is used, as the name suggests, to make paint dry slower. GW paint, if you spread it thin really does dry quickly. Do and experiment, spread a thin streak over plastic and see how long it takes to dry. It pretty quick.
This stuff gives you the chance to work with your paint for two things. One, it'll let you actually get an even coat. GW paint can dry so fast that if you're doing something like a shield or a sword, you dip enough paint to get half of it evenly, then you stop and dip again and by the time you get back to the sword the paint on it is half dry and when you stroke over it it globs up and then leaves a dry ring at the edges and just isn't smooth.
Slow dry just needs a few drops to really open up that working window. I'll add about 10 or so drops to a 1 oz bottle of my medium added GW paint. When I want to do a wet blend I'll add a drop to about 5 or 7 drops of paint. It doesn't make the paint wet for days, but gives you an extra 15 or 30 seconds of work time that'll let you push the colors back and forth like you want.
When I describe Glazing Medium to people I say its like anti-wash. The use of this is to create even layers and keeps paint from settling into cracks and recesses the way wash does.
On side effect I really like with this medium is the texture it gives when sprayed. I'll usually mix a really thin 4:1 layer of some darker color and spray the whole model when I'm done with all my airbrush highlighting. For example: I base coat dark angels green, high light snot green and then scorpion green, wash black, then glaze medium snot green. This helps seal the model and helps prevents that Gesso primer from coming up so easily as well.
Also, if you're looking to do OSL, this is a good product to pick up as well. You can do it with matte medium, but it might look better with this stuff since that's its design (thin layers). A good sample of the use of glaze medium is in Les Bursley's video where he paints the Nurgle Greater Demon from Ultra Forge. He uses it to add a slight purple color to low lights. I use it to make veins look like they're under the skin or scars or lips.
Windex is good for cutting GW paint for airbrush use. Liquitex sells an airbrush medium but I've never used it because Windex is cheap, readily available and works.
When I was searching for something to thin paint for an airbrush my goal was to just get something thin enough to spray at 20-30 psi and not clog up constantly. Adding water to paint just causes it to dry faster so whenever I was using that it just clogged constantly.
I've heard that windex causes paint to break down so I guess I wouldn't recommend thinning and storing your paint. Whenever I spray I will just mix the paint in the cup on my airbrush, meaning I drop the GW paint I added mediums to into my cup and then add about and equal amount of windex. and go to town. When I'm done I'll then just suck whatever is left in the cup back up into my little squeezy bottle. That means I do add a little bit of windex to my paint but I figure its such a small amount it won't matter. Hasn't yet.
I bought some of this in hopes that it would be a super fine sheen kind of like when you look at gasoline in water and it has that rainbow kind of shine to it.
Its not. Its opaque glitter flakes. So, when that said, this is more of a warning of what this product isn't. If you wanted to make a red metal or a black metal then you can if you use this, but if you want to paint it on as a clear coat to make Tyranids look different then this isn't the product for you.
This varnish is about the best matte varnish I've used. I like it because its brush on so you're not totally screwed when the humidity is just off and now your mini is covered in fuzz.
It doesn't dry completely matte, but it is relatively matte to what some other varnishes that claim to be matte do but it still adds a shine to it, sadly.
Typically though, I'm fine not even adding a varnish to my mini. I've had more mini's ruined with varnish, than I've had saved by varnish.
High Gloss Varnish
As its name suggests, this is a very very high gloss varnish. I uses this when I need something to look wet or shinny. I use it on eye balls, teeth, monstrous creatures mouths, gems, lights, ect. Its a good tool to have to help you be lazy and not have to make something look like its reflecting.
Well readers, that's about all I know about mediums in a nut shell. I hope this article helps to clear up any questions about mediums and sparks you to go out and get some mediums and start having those terrible GW pots work for you instead of you pulling your hair out when using them and destroying your brushes.
As always, questions and comments are welcome!
Oh, and here: (they won't care about the expiration date...usually)