Using grain or pore fillers and finishing african mahogany?
I’m in the process of completeing a buffet made from African Mahogany. I don’t want to ruin the piece in the finishing process due to my lack of experience. I plan on using a trans Tint to color (and even out) the wood and want a tabletop smooth gloss finish, but was told I could get the same results spraying several coats of lacquer and then sanding instead of using the grain filler, etc? This seems counter to everything I’ve read? If using a grain filler is the answer, is there a recommended product? I’m still trying to determine the best finish method for this project, but considered spraying a waterborne lacquer to get a durable gloss finsih. Any assistance would be appreciated.
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You can fill pores with finish, such as lacquer, but depending on the solids content of what you are spraying in may take quite a few coats. The process is to apply finish and then sand back to a point where you can sand evenly without having shiny spots in the depressions of of pores. But this is very nerve racking if you are having to do this over a dyed surface since that means you shouldn't risk cutting through the finish (and dye). That can be repaired but it sometimes takes a bit of fiddling.
Pore fillers, applied over a surface that has been dyed and then sealed do an excellent job. Fillers with high silica content shrink less. Sherwin Williams has one is all silica, but is only available in gallons, making it pricy. Old Masters grain filler is also very high in silica content. The advantage of pore filler is that, when you tint it, you obtain another tool to make your finish more interesting.
Describe the look of the finish you have in mind? There may be some other sequences of finish that could optimize you end result,
If you do go with a waterborne acyrlic besure to give it some amber tone. There isn't much that looks stranger on mahogany than a blue tint that shows when the light hits it just so.
Thanks very much for the input and advice. As for the finish I wanted to achieve, I wanted to not mask or cover the character of the grain in the mahogany. I thought the grain fillers may contribute to covering the grain. The look I'd like to achieve is a durable gloss table top finish that can withstand cups, glasses, plates, etc. as the finished piece will need to endure this things.
IInitially, I wanted to go with the waterborne acyrlic but I'm starting to realize using regular lacquer could be a better choice. Your comments regarding the "blue tint" is enough to guide me to other choices as I would rather have a more natural look (in spite of the gloss finish). I'm also thinking using shellac would support filling the grain and applying the lacquer as a final coat? I also just read about another grain filler (Target's Clear HSF5100) as an option as opposed to simply using lacquer to fill the pores. Again, I appreciate the comments and support.
Plan on at least a couple weeks after the final coat, and before final buffing, for on-going shrinkage of the finish and/or filler. If you use finish, there may be more shrinkage after the final coat, because of the overall thickness of the finish. I think grain filler shrinks less, especially with higher silica content as explained.
If you intend using nitrocellulose lacquer as a top coat, you have to be quite consistant with the prior coats. For example, the strong solvents in lacquer can damage varnish, ruling out the combination of varnish to fill pores and lacquer top coat. You also mentioned inexperience with finishing in your original post. Does that extend to spraying? Spray techniques do have a learning curve and important projects may not be the place to learn.
If pore filler is applied over wood that has been sealed, it will not really obscure the grain, but actually enhance it because you will be filling pores with a color that you have chosen to enhance the overall look. The sealer means that almost all of the pore filler will be wiped off of the surface just remaining in the pores--nothing is hidden. You must allow the pore filler plenty of time to cure before top coating, but it can be an effective product in generating a rich looking finish.
Lacquer isn't all that durable and low maintenance. It's quite susceptible to water damage (all those remedies for "white rings" are primarily designed for lacquer finishes.) For that matter waterborne topcoats are fairly similar to lacquer in vulnerabilities. For durability, varnish is king, given that catalyzed lacquers and conversion varnishes generally require more in the way of spray facilities that protect the applicator and environment than non-commercial users can muster. Lacquer used to be the universal factory furniture finish, but in a age where we were also universally expected to use coasters and hot pads religiously.
Varnish can be thin and not built to a thick plastic looking finish. The plastic look is a lot easier to avoid if non-polyurethane varnish is used. That's because the non-poly varnishes are clearer and it is the cloudiness that generates the awareness of thickness and the plastic appearance. Varnish isn't a finish recommended for spraying, but wipe on varnish is relatively fool proof, yet can yield outstanding results.
Let me work through a plain vanilla schedule that none-the-less can give quite respectable results without risk of failure. I agree that a dye step should be first, though I would use a watersoluble powdered dye instead of the multi-solvent concentrate such as TransTint. Why? Because just about any finish coat applied over the TransTint would have a solvent that could dissolve it, with the potential to muddy that coat.
Then I would seal that dye with 1 1/2 to 2 lb. cut shellac. This can be either light colored (blonde) like Seal Coat, or a darker shellac if you want added color.
Next comes the pore filler, such as that from Old Master. You would want to tint this to a shade a bit darker than your dyed base color. Tinting can be done with artists oil colors. This is applied and excess wiped off. Since the wood will be largely sealed by the shellac, the pore filler has only a minor effect outside the pores. Let this cure well, generally longer than the label suggests.
Then for the top coat I would suggest a wiping varnish. If your over all coloration is medium or darker I would use one of the phenolic resin varnishes, either Behlen Rockhard, thinned with about equal parts of Reducer, or Waterlox, either Satin, Gloss, or Original/Sealer. The Waterlox O/S is already thin enough for wiping, the others require a bit more thinning. You can use several more coats on the top to provide extra protection than you would need on the base.
Okay, I've tried to post this now for the third time so I apologize for the delay in responding to your comments. I appreciate the input and the comments you provided. You make several very good points that have caused me to rethink my approach to finishing this project. For that, I’m appreciative. I do have a few more questions relative to your advice if you wouldn’t mind providing additional remarks?
With regard to spaying the lacquer, I have limited experience. Since I would rather not do anything that would damage or otherwise make the piece look badly when complete, I think using varnish seems like the right approach. As you already mentioned, I would rather not use this item to learn on.
With that in mind, will/can the varnish give me the same glossy, hard, and clear look that lacquer provides? I think your comment about thinning the lacquer should give this type of result, but wanted to ask nonetheless? I also assume since this is a thinned product, wiping it on in thin coats with a rag would provide the best results?
You’ve convinced me the pore filler is the right way to go as well. I noted that you recommend Old Master’s. Based on your comment about adding additional (a shade bit darker) color to the pore filler to generate a richer finish, it sounds like using one of the “clear” pore fillers may not give me the results of showing the depth of the grain? Your comment leads me to believe the additional tinting to the filler may give this same result?
I had already purchased the “red Mahogany” TransTint dye that I planned to use. But your comment about potentially “muddying” the coat makes me think I should find the water-soluble powdered dye you mentioned? Since I’ve never used this product, is there anything I should know in advance or is there a specific product I should look for?
Finally, as for the topcoat, I have used Waterlox in the past and like the ease of use. However, I noticed in a few sample pieces that it seemed to give it a more amber look that muted the red of the mahogany? This could be my imagination though. Regardless, it sounds like the Behlen Rockhard, thinned with about equal parts of Reducer could be the answer. Any thoughts on this as well?
Again, thanks very much for the guidance and mentoring on this project. Your experience is clear and the teaching points you’ve provided thus far are things I will long remember. For that I appreciate again all your expertise.
You arel right that Waterlox will have an ambering effect. I usually like that on relatively dark shades, but if it doesn't work for you you could use a lighter colored varnish such as Pratt & Lambert 38. The P&L would need to be thinned with about an equal portion of thinner. Rockhard and Waterlox are about equally amber since they are both made with phenolic resin. The P&L is an alkyd resin varnish with soya oil and would be quite a bit lighter.
TransFast sold by Jeff Jewitt at http://www.homesteadfinishingproducts.com would have a very similar color to the TransTint. You could also choose from among the many mahogany dyes made by W.D. Lockhart. Red mahogany is quite red and doesn't look much like mahogany to me but that's a matter of personal preference.
Varnish isn't quite as measurably hard as solvent based lacquer, but is tougher. Gloss finishes just short of super plastic are possible with varnishes not quite as shiney as highly polished lacquer but very glossy nonetheless. Varnish is much more resistant to water and household cleaners than lacquer and generally quite a bit longer lived.
You arel right that Waterlox will have an ambering effect. I usually like that on relatively dark shades, but if it doesn't work for you you could use a lighter colored varnish such as Pratt & Lambert 38. The P&L would need to be thinned with about an equal portion of thinner. Rockhard and Waterlox are about equally amber since they are both made with phenolic resin. The P&L is an alkyd resin varnish with soya oil and would be quite a bit lighter.
TransFast sold by Jeff Jewitt at http://www.homesteadfinishingproducts.com would have a very similar color to the TransTint. You could also choose from among the many mahogany dyes made by W.D. Lockhart. Red mahogany is quite red and doesn't look much like mahogany to me but that's a matter of personal preference.
Varnish isn't quite as measurably hard as solvent based lacquer, but is tougher. Gloss finishes just short of super plastic are possible with varnishes not quite as shiney as highly polished lacquer but very glossy nonetheless. Varnish is much more resistant to water and household cleaners than lacquer and generally quite a bit longer lived.
Thanks again for the added input. Your comment about the red mahogany being quite red and not looking like real mahogany causes me to think adding more brown could solve the problem? I don't want to get a look that is not realistic or artificial and simply wanted to bring out the red colors in the wood. I also started to think the amber color the varnish gives could help tone this down a bit. Any thoughts on this?
You have to decide what you like. I recommend that you take some time to look at high quality mahogany pieces. One standard is found among antiques. The museum at Colonial Williamsburg has some wonderful pieces. Other historical sites abound in VA.
Again, thanks for the sound advice. I have been looking at more pieces and will take the time to look at those high quality pieces to ensure the right color. From those I've seen recently I tend to agree that most are more brown with some red markings. I also plan to do the complete finishing process on scrap so as to gain the experience and make sure the right color and finish. Again, thanks.
Can't add anything to the advice given, except to try out one or more COMPLETE finish schedules on some similar boards first, even if you have to buy some more lumber and surface as the piece was prepared (planing, sanding, both, whatever).
Each step in the finishing process can change the look slightly, hence the suggestion to work through the entire schedule. Keep notes, and you'll also have good sample boards for your next project.
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