Tuesday, February 5, 2019

Sealing the deal

Today's first Tutorial Tuesday post comes tackles the very real issues posed by spray sealers. Thank you, Meghan Namaste for sharing this hard-earned advice!

Troubleshooting Sealing Mishaps

by Meghan Namaste

Sealing causes a lot of anxiety for artists, and for good reason. It’s a crucial step in the process - you are “setting” and preserving the work you’ve done in order to move onto the next step. Or if it’s the final seal, it’s the last frontier before having a finished model. But sometimes it can go wrong, and nothing is more gut-wrenching than having a sealing mishap undo all your hard work on a piece you’re very attached to. As an artist who’s made almost every mistake in the book, here is a rundown on the most common sealing problems and how to avoid or salvage them.

The first point I’m going to make is that sealing is a skill in and of itself. This is often overlooked in tutorials and in our own minds, we focus so much on the creative process rather than the “boring” detail of using a spray can, which, in reality, is not so easy to do correctly! Remember the phrase, “an ounce of prevention is worth a pound of cure”? If you are new to this, I strongly suggest practicing your technique and getting a feel for using the aerosol cans on some cheap bodies before you spray something you put a lot of work into.

If you read the spray can, it does give you some information on proper usage, but I tend to use it as a guideline rather than trying to follow it to the letter. For example, once a spray can is less than half full (or half empty, depending), I only shake it for 1 minute prior to spraying instead of the recommended two minutes. And my sealer can recommends spraying ten to twelve inches away, but I spray much closer (probably five to six inches), turning the model as I go to make sure I reach all angles. It’s very easy to “miss” out of the way places, such as underneath the jaw or the back of the legs, and that can cause problems with uneven color and graininess down the line if some areas are sealed and others aren’t. I make sure to saturate the horse without blasting it, because I find that helps keep the color nice and smooth. The spray will turn matte almost immediately as it sets, but you should look for that nice, even sheen as you spray it, which tells you you’re getting good coverage.
This photo shows a model immediately post-sealing. The head and neck area were sprayed last, as evidenced by the slight sheen. This is a nice, normal sealer layer. Now I’ll go over what to do when things go wrong.

(Not Quite) 99 (Sealing) Problems

The first and probably most devastating sealing problem is crackling.
This can happen with both primer and sealer, and several factors can cause it, namely spraying too heavily, humidity, and the underlying model or paint layer not being clean or dry enough. It’s very important to try to prevent this from happening, as once it occurs, you’re pretty much stuck sanding it down and trying again (in the photos, you can see that I did a very poor attempt at covering up the crackling with white markings on this early custom of mine). If the crackling is mild and isolated to one spot, you may have luck taking a dry paintbrush and pressing the crackled area down into the model to smooth it out before the sealer dries, but this is kind of a last-ditch, high-risk fix. My best advice is to watch the humidity, watch your spraying technique, and when prepping any model that might have grease or mold release, make sure to aggressively de-grease and wash them prior to priming.

The other problem that can occur from overzealous sealing are drips. It doesn’t crackle (good!) but it does get a big ‘ol drip down the side (ugh!). Again, sanding is going to need to happen, unless you get really lucky and it dries smooth enough that you can blend it with further layers of paint/sealer.

So what usually happens next, if you’re anything like me, is you might think that the solution to those horrible problems above is to spray super lightly. But that kind of thinking brings a host of new problems. Spraying too gingerly or from too far away means that the spray is already dry by the time it hits your model. This causes a crusty, dry, gritty texture, insufficient coverage, and terrible graininess, if you’re working in pastels.
This resin has been a successful show horse for me, but he’s hiding something under that brindle coat. If you turn him just right you can still see the remnants of this gritty texture, because at the time I didn’t know to sand and re-prime, I simply painted over the failed paint job. This horse had a happy ending, but he definitely did not end up in my originally intended color for him, simply due to sealer error.

On the subject of graininess, this is sometimes a natural side effect of working with pastels. I don’t always struggle with grain on my pieces, but some of my most successful horses have started out as a grainy mess. The answer (much like the universal trainer’s cry of “More leg!”) is more layers. In this picture you can see at the lower edges of her belly how grainy she started out, and how smooth the color has become.
So here’s a few more tips to avoid problems. Always, ALWAYS test every new can of sealer on a sacrificial body horse, or if you’re like me and too lazy to go get the body horse, at least test spray it on the belly or another inconspicuous area first. Bad sealer cans are rare, but you never know how long they’ve been sitting on the store shelf, or how good the company’s QC is (remember, an ounce of prevention). If possible, avoid spraying in high humidity, as it can sometimes cause the sealer to go “cloudy” and give the model a “frosted” look. This can actually be fixed by re-sealing later, but it’s not fun to see your model turn whitish, and it will make your blood pressure spike. Similarly, try to avoid the “whoops, I grabbed my primer instead of my clear sealer” mistake - there really is no fixing that one.

Speaking from experience, cans will start to get spitty and not spray right once they get close to empty. Please do not try to keep using them on models once they start to sputter. Save those “remnants” for things like bases, where perfect coverage doesn’t matter. I learned this one the hard way when I almost ruined a finished model using a can that should have been retired. I knew it wasn’t spraying great anymore, but I stubbornly didn’t want to start a new can right then, so I went ahead and used the old can. It spit out huge drip drops, all over the side of my finished resin.

When this happens, the first instinct is to try to smooth down the drips with your finger. DO NOT DO THIS. I repeat, do not attempt this “fix”. It will not work, and it will rip off all the layers of paint and leave a bald spot, a wrinkle, or something else equally Not Good. The only thing to do in this situation is to keep your wits about you, act fast, and spray the heck out of those areas that got dripped on. Forget everything I told you about heavy spraying causing crackling, etc., and just try to get the can working well enough to coat the model with a nice thick layer. You only have seconds to do this, because once the sealer dries, hitting it with more sealer isn’t going to do any good. But adding a thick layer of sealer over still-wet sealer will blend those drips in. I was able to do this, and the model was fine. But once again, making better choices would have prevented all that panic completely.

One other thing I want to touch on is that in this hobby you will hear lots of horror stories about every product imaginable. All I will say about that is that any brand of sealer can have a bad can, and any brand of sealer can be improperly used and have issues that way. Dullcote is extremely popular, but it’s not available in my area so I’ve always used Krylon. Yes, I’ve had issues with it occasionally, but mostly due to my own human error (see above). My point is, don’t let bad reviews scare you off from different sealer brands. A lot of that is personal preference, as well as what’s available in your area. No product is magic, they all need to be used correctly in order to have the desired effect.

Last but not least, please protect yourself and wear a respirator, not a little particulate mask, but an actual vapor respirator. They aren’t expensive, and you don’t want to be breathing in those chemicals, especially if you are pregnant (the chemicals are indicated to cause birth defects), or just, you know, if you think you may want to have healthy lungs in the future whether or not you have tiny humans to care for.
Happy spraying! Remember, practice makes perfect, and preventing mistakes is way better than fixing them.

1 comment:

  1. Great info! But one thing I have seen problems with is the sealer becoming sticky and just never seems to dry. Any ideas on how to fix this problem?