Print Varnish Tips
In this week’s episode, we cover print varnish tips and common problems relating to varnish application. Mixing, timing, using custom ICC profiles, handling a HVLP spray gun, and more.
Without using the proper varnish application techniques, you can end up with bubbles on your canvas, or prints can come out too dark or too light. It can become frustrating when you encounter varnish problems especially after spending countless hours editing, color managing, and printing your work.
In this week’s episode, our very own Justin Bodin covers questions all about print varnish. He addresses some common problems associated with print varnish and provides solutions to make your print varnishing experience, well, responsible.
Even if you may not be facing problems with coating your prints now, it’s always great to know solutions before you actually experience it yourself.
- Whether to use varnish on a metal inkjet image
- Stacking or mixing different types of varnish
- The timing between applying varnish and stretching the canvas
- Mixing a varnish container that doesn’t have a large enough opening
- Measuring ICC profiles for canvases with or without varnish applied
- Checklist to use when handling a HVLP spray gun
- Much more!
Listen in to learn about print varnish tips and common problems
#AskBC Episode 40: Print Varnish Tips: Common Problems & Solutions
Varnish can almost feel like an afterthought to the whole printmaking process. After editing your image and doing the color management work to get that perfect print all that’s left to do is apply a coat of varnish to protect it, right?
Yes, but sometimes frustrating issues like bubbles, cloudiness in the coating, dark or light looking prints can pop up when using improper varnish application techniques. These issues really kill the excitement of finishing a great new piece of art so let’s address some of those issues here.
First off, Breathing Color sells two equally awesome varnishes. There’s Timeless and there’s Glamour 2.
Timeless, comes in gloss, satin, and matte finishes while Glamour 2 comes in gloss and matte. Timeless does have the benefit of being a quicker drying varnish, which can be beneficial to some people with space concerns. You also don’t have to dilute Timeless with distilled water the way you do with the concentrated formula of Glamour 2.
We typically recommend Timeless varnish in 90% of cases. The only time where we don’t recommend Timeless is if you’re hand rolling very large prints with a foam roller since Timeless dries quickly. If you’re trying to hand roll a print that’s very large, the quick drying process can impede your ability to coat the print before the varnish becomes tacky. This leads to a texture developing on the print, which is almost impossible to get rid of. So, stick with Glamour 2 if you’re rolling very large prints and Timeless if you’re doing smaller prints or spraying with an HVLP gun.
If you’re already using one of these varnishes successfully we typically don’t recommend switching unless absolutely necessary. When you’ve already learned the process with one varnish it can be challenging to learn or relearn a different process. Please don’t let us stop you from trying something new but just make sure you’re not in the middle of an urgent job and have plenty of time to learn a new process.
Can you use glamour 2 to coat metal inkjet images?
If you’re asking about dye sublimation on metal, those are really bulletproof and don’t require a top coat. They should be scratch resistant, flame resistant, pretty much anything resistant right away. If you try to coat a sublimated metal print, you’ll likely get a strange finish with Timeless because the aluminum isn’t porous or absorbent. This can create bubbles that pop on the surface and leave a pitting effect. We haven’t done a lot of testing on this so you might be able to play with an HVLP sprayer and use Glamour 2 or Timeless to spray the metal with extremely thin coats. With care it may be possible to layer on enough varnish to get the effect you’re looking for.
Coating metal is going to be tough and even coating something like metallic photo paper will encounter the same issues. Using water based coatings to coat non porous materials like metal or an RC photo paper just isn’t the best idea as they are more ideal for cotton based fine art paper or canvas. I would lean more towards something that’s aerosol and lacquer based or solvent based for coating metal or photo paper. There are a few different brands out there like Liquitex and Golden that make aerosol based top coat varnishes and one of those would be much more suitable for this situation.
Can you stack different varnish finishes on top of each other?
So for example, can you throw a coat of Timeless matte on top of a layer of Timeless gloss to dull the gloss level or vice versa?
You absolutely can apply multiple coats of varnish that are a different sheen as they are totally compatible. However, there are a couple of different ways to handle this. Most commonly we see customers mix the two varnish finishes prior to applying them via roller or sprayer. For instance, you can take a certain percentage of gloss and a certain percentage of matte then duplicate that mixture each time you varnish a print.
We recommend mixing the exact amount you’re going to use and then using all of it to avoid waste and the varnish going bad. It’s wise to run through some tests and figure out what works best for you. Coating as part of the printmaking process is something that people frequently customize to get the particular effect that they’re looking for so feel free to play around with it. Generally speaking, you’re not going to screw it up permanently, so feel free to experiment.
Once my canvas has been coated with timeless and is dry, should I stretch it right away or can I leave it? And if I can leave it, how long can I leave it?
You can leave a varnished print sitting around for however long you need. There’s not really a max once it’s varnished as the print has reached its most durable state. Assuming that your print isn’t experiencing any drastic shifts in temperature or humidity you’ll be fine storing it for as long as you need to before stretching.
How do you recommend mixing the one-quart sizes of Timeless varnish since the container does not have an opening large enough to insert a stirring device?
The Timeless pints, quart and gallon sizes come with a pretty small opening that is difficult to fit a stirring stick inside of. We highly advise never using a wooden stirring stick or device to stir varnish as you introduce acid into the mix which can cause yellowing or other discolorations in prints. By introducing acid to a jug of varnish you’ve just cursed any prints that are varnished with that batch, so no wood but plastic or metal is acceptable.
Ideally all you’ll need to do is take the gallon or the quart or the pint, whatever it might be that you’re mixing and slowly invert it maybe 20 or 30 times. You don’t want to shake it to introduce unnecessary bubbling because it can take a while for those bubbles to settle. Just do it for a minute or so until it looks well mixed. The matte and satin versions have silica matting agents that will begin to settle to the bottom so be sure to spend more time on those finishes than the gloss.
When you make a custom ICC profile for canvas, do you measure the targets with or without varnish applied?
This is a highly debated topic from the forums we’ve looked at, but for the most part, we measure the targets without varnish.
If you download our ICC profiles you won’t see an unvarnished target, a matte, satin, and gloss target as we’d have to have six or eight different variations considering we have two different coatings with five different coating variations. It would require a massive library for us to keep track of, and based on the testing we’ve done we haven’t noticed a considerable difference between a target that’s varnished versus one that’s unvarnished. For now, we scan the targets that have not been varnished, so that’s what you would be downloading from our website.
I’m spraying Timeless gloss from an HVLP sprayer and I’m getting bubbles or air pockets on the prints, and they do not dry out. It leaves little uneven spots all over the canvas right in the middle of a big job. Of course, I’m not sure what to do, any suggestions?
95% of the time getting bubbles or air pockets in the middle of the print is an issue with the amount of Timeless or the amount of air that’s coming out of the gun. It’s basically a settings issue where the varnish is not atomizing correctly or it’s hitting the print in too large of a droplet and causing the varnish to not dry properly.
Troubleshooting this kind of issue with one of our techs over the phone is usually best in a situation like this but here is a checklist for HVLP problems when spraying timeless.
- Take a step back and evaluate the spray that’s coming out of the HVLP gun. You can get to a good starting point using just water in the gun but feel free to use Timeless if you want.
- Set up a piece of cardboard that you can spray to evaluate the spray pattern.
- Fill the guns reservoir with Timeless or water.
- Hold the gun about 12 to 15 inches away from the print and spray.
- Evaluate the spray pattern that’s coming out which you’ll want to be in a fan pattern and not like a conical shape. Make sure you’re fanning it out, whether that’s a horizontal fan or a vertical fan, depending on which way your hand is moving. The nozzle setting is key here. You want it to be a vertical fan if when you’re moving left to right, and you can do a horizontal fan when you’re moving up and down
- Make sure that at 12-15 inches the varnish is hitting the print in a fine mist. If you’re seeing larger globs kind of spreading out when hitting the cardboard, then you want to either reduce the amount of varnish or increase the amount of air.
- If your fan diameter goes too far over 12 inches, then you know have too much air pressure. So you want to decrease the air pressure until you’re around 12 inches. And if at that air pressure and at at 12 inches you’re still seeing globs, then you know need to decrease the volume of Timeless a bit to even out that mist coming out of the gun.
- Be sure to move your hand speed at about 12 inches per second.
- If using a compressor be very mindful about what your regulator pressure is on the compressor. You want to keep that between 30 and 50 psi.
- Always make sure that your coating is within its shelf life. You get about one year from the purchase date on Timeless, so make sure it’s not something that’s super old. Also, make sure that you mix it very well.
Another common issue we see with Timeless and HVLP guns is in between prints. Printmakers will spray one print, lay the gun down for 10 or 20 minutes to set up another print, then pick up the gun to spray which is when they run into a variety of issues.
Generally, they’ll see sputtering or spattering that’s happening where the print varnish isn’t coming out of the nozzle smoothly, and that’s because Timeless dries rapidly and it can start to dry up in the nozzle. To remedy this, anytime you set your gun down make sure to wrap a damp cloth over the nozzle and this will prevent varnish from drying in the nozzle tip.
Lastly if you’re getting too much coating in the middle of your print your technique may need some adjusting. We generally recommend spraying vertically and covering the print completely, then rotating the print or just rotating the nozzle fan direction and use hand travel to spray in the other direction.
- Go vertically once and cover the print.
- Go horizontally once and cover the print again.
- Let that dry as coat number one and then go back and apply a second coat to it.
The goal is to not apply too much varnish in one coat which can create different problems with drying like bubbles forming and then pits being created after those bubbles pop.
It pays to be mindful of how much coating you’re laying down. Again, about one foot per second with your hand speed. Cover the print once vertically, once horizontally, let dry for 25 minutes, and then apply a second coat.
We hope you find this information valuable and as always if you have more questions please feel free to schedule a call with one of our reps.