Topcoat Adhesion over Stain Markers

Stain markers can interact with finishes, as this example demonstrates. November 12, 2006

Question
I used Minwax stain markers to touch up some older cabinet doors. Before applying, I used TSP followed by lacquer thinner to clean the surface, then sanded lightly. I got a great match of the original color with the markers. I let the doors dry for a day or two, misted the area with de-waxed shellac, then shot the whole door with pre-cat lacquer. The areas where I used the markers did not take the topcoat. It bubbled up, and the topcoat can be scraped off with a fingernail. It's gummy, too. Any clues why this is happening?

Forum Responses
(Finishing Forum)
From contributor R:
It almost has to be something in the markers, although not getting shellac to stick can be a trick. I am wondering what might be in the markers beside stain or dye. If it is one of the old "furniture repair kit" markers they sold (or may still sell), I think it has some kind of sealer/wax in it as well as the coloring agent to make the repair have a gleam to it when you use the marker. You will probably have to clean that stuff off and start over on your coloring with another product.



From the original questioner:
The markers contain mineral spirits. I suspect my problem is that I didn't quite sand down to the bare wood, so the stain was kind of sitting on the surface and not drying completely. So I sanded it all off, this time to bare wood in the damaged areas. I put down an alcohol-based dye to get the background color, now fooling around with various TransTint colors in shellac on top of that as a toner to try and match the color. I'm getting close, but blending the color and sheen into the surrounding areas is tough! Hats off to the refinishers who are good at this.


From contributor M:
Most markers contain alcohol, which is why they dry so fast (much faster than MS). Try omitting the shellac, and try misting the touchups before you apply the flow coats.


From the original questioner:
Thanks. I'm planning to order some Mohawk markers. Do you know if they're alcohol-based? They have several different types. I had another theory pop into my head today. The worst areas were on base cabinet doors that were around the sink. I was thinking maybe years of soap contamination needed more than the application of TSP and lacquer thinner I hit them with. What's a good solvent for soap accumulation? Besides water, of course...


From contributor M:
You're really lucky that the TSP and the lacquer thinners did not soften up the topcoat. TSP is a powerful cleaner when used full strength. Quit while you're ahead. You must be working on a 2 component finish - that's why you either did not remove or soften the finish. Did you try to mist and flow coat it without using the shellac as a sealer?


From the original questioner:
I doubt it's a 2-component finish. More likely, it's something old school, like varnish or lacquer. The TSP was heavily diluted, at least 20:1. What would you recommend as a good choice for cleaning and wax removal? I used the lacquer thinner on the worn areas, hoping it would clean up the remains of the old finish and allow the stain to penetrate. Wouldn't any softening be temporary, i.e., just until the lacquer thinner evaporated? I did not get a chance to try your suggestion yet. What's the thinking behind skipping the shellac?


From contributor M:
Then you're lucky that it was diluted. If it was lacquer, the lacquer thinners would have eaten it up. It could be varnish or poly. No, if it was lacquer, and you washed it down with lacquer thinners, it would have effected the lacquer permanently. My dewaxer is mineral spirits and lacquer thinner. You will need to make adjustments depending on each coating that you will be cleaning. If it's lacquer or shellac, then it's more mineral spirits and less lacquer thinner. If it's varnish or poly, increase the lacquer thinners. What's the thinking behind skipping the shellac? If the marker is alcohol or mineral spirits based and you allow it to dry, and you start out by mist coating and then follow with a flow coat, you will eliminate one step, plus you will avoid a compatibility problem over the marker.


From contributor G:
A stain marker is a marker with stain in it. Use it to touch up raw wood. A touchup marker (Dover and Mohawk are two that come to mind) is fast drying. Many of them look different after they've been lacquered, so do a test.