Spraying is more difficult than I expected and I’m afraid I’ve covered all the grain of my expensive maple. I have several coats so far and still need more to even color. I’m now sanding before final coats. How long should I allow the shellac to dry before sanding? The other problem is I can’t seem to get the color into sharp edges of my raised panels. I even used an air brush which still failed. Should I use a small brush in these recesses? Or is there another method? Finally. I’d like the final color a bit lighter than what I have now. Should I mix the dye and shellac more opaque for these final coats since the grain is totally obscured already? Help will be greatly appreciated
Thanks Ken…Palm Desert CA
Replies
Ken - are you certain you're mixing dye with your shellac? The description of obscured grain sounds like pigments, not dye. I use dyes in my finish quite a bit and have never produced an opaque look regardless of the number of coats.
Sounds like you have a few problems - uneven coloring, too dark, and incomplete coverage (corners). All these problems are related to technique.
To get even coloring, a number of finishers recommend thinning the finish a great deal (on the order of 3%-5% solids), adding a small amount of dye, and spraying multiple coats to slowly build the color and film thickness. With sufficient overlapping and box coating (spraying passes in 90 degree rotation) the coloring evens out. I don't use this method, but have seen it recommended often enough to assume it either works or sounds good enough to repeat. Seems worth trying if even coloring is a problem.
Getting the color too dark is obvious - too many coats; too much color. To avoid these type of problems, always do samples before starting your project to work out all the steps in detail. I generally try to do as large a sample as possible - a door for example, and keep a detailed list of each step. I attach the finish schedule to the back of the sample for future use. Little samples on cut-offs can produce seemingly good results, but the outcome on larger surfaces is a lot different.
Getting the colored finish into the recesses, corners, crevices, etc. is a matter of spray gun adjustment and spray technique. If the air flow is too high, the turbulence will keep the spray from covering the wood in tight spaces like corners. Reduce the air-flow as much as possible while maintaining good atomization. Keeping the viscosity of the finish low helps to get good atomization at lower air pressure/flow. On items like raised panel doors, the way you aim the spray gun as you spray the recessed areas makes a big difference. I generally start with the long side of the door facing me and spray aiming away from myself. This gets the spray into the recesses on the far side of the raised panel and the concave portion closest to me. Then I rotate the door 180 degrees and finish spraying it - all the recesses get an even wet coat. As the spray pass nears the top and bottom ends of the door, I angle the gun towards that end while maintaining an even distance from the surface. This gets the recesses at the ends of the raised panel.
With the finish being too dark already, you have a decision to make. Do you remove the finish and start over? Or do you mix a toner with white pigments combined with the colorants you are currently using and "paint" the piece a lighter color? It's your choice.
Paul
F'burg, VA
Paul:
Thanks for your insightful comments. The color I've used is called color fX dye concentrate from woodfinishing supplies.com. Like I said the color is now quite opaque. I'm going to spray some more and if it comes out even and looks good I'll leave it alone. If not I'll strip and start again.
Thanks again
Ken
Ken - the dyes you're using are good dyes. The opaque quality of the color bothers me. I have mistakenly used dye concentrates on bare wood and the color was so deep it looked like paint instead of dye. It sounds like you've gotten the same level of saturation.
If you didn't seal the wood with clear shellac before starting with the toner that would make sense to me. Otherwise, I'd say you just have way too much dye. The problem is interesting - I'll try to apply a lot more toner than normal on some test pieces to see how much is too much.
Paul
F'burg, VA
Paul: I'm sure you're correct. It's obvious to me now I made some serious mistakes. If my final spraying isn't satisfactory is the removal of several coats of shellac going to be a nightmare? Will I use alcohol if I do remove, or regular stripper?
Thanks again
Ken
Ken - lots of alcohol and rags will take the shellac off. If I were going to remove the finish, I'd probably sand with 100 grit and a random orbit sander on the flats then clean up the rest with the alcohol. My approach is whatever works the quickest and easiest is the way to go.
Paul
F'burg, VA
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