Even Finishing Techniques for Alder
Approaches for avoiding a blotchy look when finishing Alder. May 27, 2008
Question
I have a customer that is comparing a select grade alder cabinet finish to a standard alder trim finish. We need to match the cabinet's finish, so I contacted the cabinetmakers to find out what type of stain and finish they are using. This is what I found: They are using a lacquer wiping stain and applying it with a rag-on-rag-off system. The color is a cherry stain. They are then using a lacquer high build sanding sealer and a satin lacquer topcoat. My problem is this: using that same system, the standard trim that is installed becomes blotchy and inconsistent. The trim that is installed has some knots and inconsistent grain compared to the select grade that is used on the cabinets. I'm currently trying to seal the alder first and then apply the lacquer stain, dry brushing it to match the depth of the cabinets. Is this the right way to approach this, or should I try something else?
Forum Responses
(Finishing Forum)
From contributor S:
The best way to handle this would be a tinted lacquer. This will give you a uniform color without the blotchiness you get with most wiping stains. If you're not comfortable working with raw colorants, tints, and dyes, find somebody that could formulate the shading lacquer for you.
From the original questioner:
I was trying not to get into a blending phase due to the increased time and money. However, I am capable of doing this if need be. Has anyone ever tried to blend with just the lacquer based wiping stains? Or should I seal the wood first?
From contributor C:
I am about to finish alder cabinets on a job, so I can't tell you what works, but I'll share my planned approach for what it's worth. In the past I have had great success with a wash coat of cut, dewaxed shellac (Zinszer seat coat) to prevent blotching. I've found it's pretty forgiving to apply whether it's brushed or sprayed, sanded or left on. I follow this with a wiping stain, or any good heavy-bodied oil stain. I don't know how this would work with lacquer, because I don't use it much. Like I said, haven't tried it on alder yet, but it's worked well on maple for even results.
From the original questioner:
I have tried to use an oil stain conditioner and an oil wiping stain, however the grain tends to go darker and pop more with a lacquer finish. It does not match the overall appearance of the lacquer wiping stain that the cabinet company used. An alcohol base wash is not compatible with the lacquer wiping stain. The lacquer wiping stain tends to eat into the alcohol wash. I believe that the only solution that may work is to seal the wood and shade the color with a tinted lacquer topcoat. I would love to hear any other solutions.
From contributor S:
Are you able to spray or are you brushing? Mixing your stain with your lacquer may not be your best choice. If you are able to get a hold of pigments that are compatible with your lacquer that would be the way to go. Getting an alder into a cherry tone will not be too difficult. I would apply a coat of sealer to your work first, scuff down, then apply the shading lacquer to your desired color, then lightly scuff and clear coat.
From the original questioner:
I'm using a lacquer base stain that I can add to the lacquer clear coat. I do also have the pigments to add, however the contractor insists that I use the same products that the cabinet company used. Thank god they are using a lacquer based system in which I can do the same. I'm still looking for alternate solutions due to time and cost. This will be my backup plan.
I'm also wondering if there are grades of alder wood. I'm thinking that the contractor may be able to receive a higher grade of alder that does not have as many knotholes, etc. The cabinet company is using select grade alder. I'm not sure if the contractor could receive something similar. Could this be a solution? I believe that it would cut my time in half and give us a closer finish to the cabinet company.
From contributor R:
Every species of wood will have different grades. You should be able to spec out the type/grade of alder to whoever is running the trim. Of course it will cost more to have them avoid knots, sapwood, mineral streaks, etc., but if you thought this would help the overall finish, it may be worth it. Did you ask what grit they finished sanding the alder on the casework at? You can avoid some blotchiness if you, say, move up to a 220 grit when sanding your trim. I would not be surprised if the alder trim was installed without being sanded. If this were the case or they only briefly hit it with a 120, that may make enough difference in the two.
From the original questioner:
Thanks for the info. The cabinet company is finish sanding with 150 grit. On my samples I have finish sanded with 220 and have noticed a difference. I guess the more you close the grain with a higher grit, the better the finish.
From contributor J:
When we used to finish alder for furniture, we would add bentone at 10% by weight. We also would wipe it and that would make the bentone work into the wood for better hold out. Be advised, bentone can cause adhesion problems if used on other woods besides alder.
From contributor D:
You have two solutions to your problem. One is spraying NGR dye - best solution, as it's both faster and easier. The second is using glue size prior to your lacquer wiping stain, if this is the technique that's being forced upon you. The glue size will completely eliminate the blotching and is impervious to the solvent based lacquer stain, whereas the alcohol based Seal-Coat is not.
Both Custom Pak Adhesives and Franklin International make glue size. CP will sell you this in a gallon (which is mixed with water to make two gallons) and it's available for purchase on their website. The smallest container Franklin produces this in is a five gallon bucket and their version too is diluted with water. Some will tell you to make this by watering down PVA glue (this is possibly true, but I've never tried it, as I use the honest to god Franklin or CP product). The technical name for glue size is polyvinyl alcohol which is used as a chemical precursor in the production of wood glue. That's why you buy it from glue companies.
The beauty of glue-size is that it's a water based system and the lacquer or oil stain on top of it will not affect it in any way. Do not go beyond 150 grit with alder. To do so risks adhesion problems down the road. Another advantage of glue-size is that it's also an adhesion promoter. This entire question of alder grade will become irrelevant if you either spray NGR dye or use glue-size.
From the original questioner:
With the NGR dye stain, you are saying to tint it to the desired color stain, and then just spray and shade with it, correct? I would tend to agree with you on the glue sizing, however adding water based products to the wood would raise the grain. Wouldn't this be the reason for adhesion promotion?
From contributor D:
Simply use the right color of NGR dye and spray it. You're implying to add it to the clear coat... I'm not saying that; I'm saying to use it as a stain, not a toner. The raised grain is sanding off (lightly) after glue-sizing, so it doesn't play into the increased adhesion. The PVA itself improves adhesion.
When you prime bare drywall prior to painting, the products recommended for this purpose are modified glue-size. Look on a can of drywall primer at Home Depot and you'll see polyvinyl alcohol as a key ingredient in these products.
From contributor T:
I pretty much agree with contributor D. I use a water based dye to get a light background color. (For a cherry look, I use a light red or pink.) Seal it with thinned SealCoat. Glaze it with stain or glaze and then top coat. It's true that a lacquer based stain will bite into shellac, but that's a good thing, not bad, and it doesn't bite in enough to cause blotching. Shellac is often used as a barrier coat under lacquer. A lacquer stain will also bite into a lacquer wash coat. I also don't sand past 150. You're not closing the pores as much as you are removing the tooth that catches and holds the stain pigment. I don't use PVA sizing, but if you want to and you're worried about grain raising, you can use white glue thinned with alcohol. PVA drywall primer is so thick it would be of little use as sizing. I have also found wood or stain conditioners a total waste of time and money.
The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).
Comment from contributor A:
Try using clear stain prior to using any color wipe stain. Just let the clear dry for about 5 minutes, and then apply your color. Be sure to check for color match so that it is not lighter than desired. This works great on cherry too.
Comment from contributor B:
A lot is being said about finishing alder. In a nutshell, you must sand the wood to a very uniform smoothness - no less than 180-200 grit. A well sanded wood surface will accept any kind of finish. Your finished product will reflect the effort you make in preparation, particularly in sanding. Hand-scraping with a very sharp cabinet scraper is the ultimate in surface preparation, but that is hard to do on moulded trim and you need to know how to sharpen a cabinet scraper. Have someone show you. You will be surprised at the smoothness the scraper produces, and therefore eliminate splotching on "wild grain".
