Dark Glaze Over Light Lacquer (On Site)
Here's a long thread about a tricky re-glazing job, with some excellent tips and insights. July 2, 2008
Question
I just finished (SW CAB acrylic) a two-level addition door, window and trim package with a light colonial maple stain (Minwax provided by contractor) and have been asked to now match and reshoot it to the rest of the home's existing dark, mahogony-esqe woodwork. (Yes, I suggested we do that to begin with.) I have plenty of experience working with glazes and will need to layer 2 or 3 coats (between SW vinyl sealer) to achieve tone if I use my usual method and glaze formula (10% oil glazing compound, 30% stain, 60% MS). The question is this: what would you do to make a tone jump that drastic? I have at least a day of masking before I have to commit to a procedure, and I'd like to use this forum to expand my knowledge.
Forum Responses
(Finishing Forum)
From contributor T:
I would glaze the recesses and tone the rest, spraying dye diluted enough with lacquer thinner that I could make two or three passes. The toner will melt into the vinyl sealer, or I might add a bit of topcoat to keep it from looking splotchy, let flash off and topcoat.
From the original questioner:
Thanks! I was leaning that direction. Does my glaze formula sound like it's in the ball park? It's not an exact, of course, but that's about what I feel it ought to be.
From contributor T:
I never mix stain with glaze because most of my stains are too hot and will melt vinyl and nitro, but if your stain is just cut with mineral spirits, then I suppose it will work, as long as you hit the recoat window just right. For instance, my oil glaze must flash off for thirty minutes before I can seal it, but must be sealed before two hours.
From the original questioner:
By "hot", do you mean you use an accelerant like japan drier or something similar to speed dry time? Or is the stain you use hot? I should mention that I revised my glaze formula to about 40-50% stain, 10% glaze and the rest MS. I am applying with a brush, letting it set up and mottling it even with dry brushes. I like the results. How long would you allow a glaze like this to dry before you seal it? (I'm using SW vinyl sealer.)
From contributor C:
Looks like a good day for crinkling your glaze - 50% Minwax stain + glaze base + 40% mineral spirits? Maybe you'll get lucky - hope so.
From the original questioner:
I knew that it would have been wiser to build the glaze in stages, but I have some delicate parameters that force me to attempt the ridiculous. Will a few days of drying time help me avoid crinkling? Is there something I can add to the SW vinyl sealer (accelerant/thin/don't thin?) to keep my greedy, one coat plan from backfiring on me? The glaze I laid down yesterday is dry enough to handle and rub with pressure today. I have about half the room glazed so far, but I will alter my approach if I get some sagely direction. Hell, I can wipe off what I've done with MS if need be, and start over. Would a shellac sealer be less disruptive?
I don't believe in luck, so I need some real solutions. I love this forum and know that there are some crafty finishing wizards around here that will part the heavens and grace me with their genius. Thanks.
From the original questioner:
One more thing: my glaze concoction is about 10% glaze, 50% stain (the stain is equal parts SW wood classics and Old Masters penetrating stain), 40% MS. I'm aware it's unorthodox, but the glaze I worked up is a dead nuts match to the piss-poor existing. To say the old finish is "of poor quality" would be like saying the Atlantic Ocean is "damp". Get me?
From contributor C:
I don't know the base contents of your glaze product/vehicle - does it have oil? Is the penetrating stain xylol based solvent? These will affect the outcome in different ways - that's the problem when mixing unlike materials (those that have different makeup) together. Is the glaze over a lacquer base, vinyl, urethane, oil enamel, latex, etc.?
Long ago the wizards mixed everything with everything else to try to come up with elixirs. Many died in their ignorance because they did not know what might happen when unknown substances came in contact with each other. But there is no excuse now - chemistry in our field is pretty sound. You need to settle on a product line that has everything you need to accomplish all you need to accomplish - colorants, glazes, dyes, sealers, toners, shaders, fillers, primers, clear coats, etc. Mixing different brands is not the way to go unless you know enough chemistry that you're positive of the outcome!
Make up samples before you begin any job, so you know what the outcome will be before you get yourself in a fix like you're in.
Yes, you can use shellac as a barrier coat, but how it will hold up in your situation, who knows? Is strong sunlight falling on your work? Are the dye colors in your formula fade resistant? How much will the color change and how fast? Pigments usually fade little. Dyes? Another story all together. I have no for sure answers for you, except starting over.
From contributor G:
Contributor C is fully correct on the use of one product line. That way you will have backup from the supplier in case of finish problems. If all you need to do is make the light maple look like mahogany, why not skip the glaze step and mist on something like diluted MLC Microton? I think that would be a lot quicker. If you have to, you can use Microton in the topcoat as well, to fine tune your color.
From contributor C:
That's a good idea, but I was thinking that if the areas he's talking of are receiving a lot of direct sunlight, they may fade in a year or so, especially the red colors which are more prone to fading, leaving behind the other color components - yellow, blue, etc., which in turn would no longer match.
From contributor G:
I've found that the blues fade more than reds, but fading in the windows could be a concern. This concern would have existed even if the windows were stained in mahogany in the first place. One way to deal with it is to make the shading lacquer with red oxide and lamp black, which won't fade. Contributor C has made suggestions in other posts about UV blockers that can be used. Window film, shades and blinds will help and will probably still be cheaper than redoing the window trim every couple years.
From the original questioner:
In lieu of digging through past forums and deep consideration of all the well thought out suggestions on this thread, I have decided to test locking in the glaze I have laid down. (After much fiddling around, I have ended up using 10% SW oil glaze, 50% MS, and 50% mixed stain - 1/2 Minwax English chestnut, 1/4 Old Masters red mahogany penetrating stain, and 1/4 Old Masters dark mahogany penetrating stain). In the future, I'll revise my arsenal to a non-stain based glaze.
Rather than using a tight window of flash time to seal the glaze, I'm letting everything dry for several days, and trying two coats of barely thinned SW vinyl sealer fogged on. If the first looks sketchy, I'm switching to a dewaxed shellac sealer, and using the same tack coat approach.
If I weren't matching to such crappy existing woodwork, I wouldn't dream of going this route. I intentionally glazed the new wood variation-free in hopes that the sealer will give it a bit of rustic character to match the old. I also went a bit light on the initial glaze coat to allow room for adjustment on a second coat.
If anyone wants to weigh in on a technique or sealer that would cause the least disruption to such a glaze, for the love of all that is sacred, please weigh in!
From contributor C:
When you finish this job, start buying a set of colorants that you can use to mix stains/glazes from scratch. If you're capable of blending so many different brands of products together to come up with what you need, then you should have no trouble using straight monochromatic colors to mix any color you may need instead of buying pre-mixed products of all sorts with varying chemistry to do so. This is what a true finisher knows how to do - mix colors from scratch, not blend others' stains together, unless that is all that's available. If you do this, then you have complete control over the chemistry and the outcome and how long before you can spray and how thick you can apply it and all the other areas of concern. Buying premixed stains/glazes is a waste of money. I can't remember the last time I purchased premixed stains. This will also sharpen up your color theory acuteness and make you a better colorist than you presently are.
From the original questioner:
I'm happy to report that the glaze I laid down a few days ago was sealed today using the tack coat method suggested on this thread with total success. I let the tack coat set for two minutes at most until it flashed, and followed up with a wet coat. I used an HVLP gravity fed gun and was generous with the air mix to encourage drying on the tack coat. I tried the window method also suggested here on a sample first, then on all the trim on the first floor, and will be using this for the rest of this job and beyond. I let the glaze flash off, and sealed it between 30 minutes to 2 hours after that with absolutely flawless results. This technique will be my new MO from here on when working with glazes. I used SW vinyl and was stunned to see it behave so well. I usually hate the stuff. I shaved at least 2 days off my timeline and I have this forum and all you guys to thank for it.
From the original questioner:
I've finished the job and somehow, everything turned out great. I got called back to match and finish a bunch of built in custom cabs and a window seat. I'm so grateful to have these threads and all you guys who are true craftsmen of the old school, to take the time to help a brother out. As the old saying goes, "if you love what you do, you will never have a job." Thanks.
