Finishing Maple

[Jim Benante]

Newbie here so please forgive what I will call innocence.

I am building a crib out of maple with some canary wood accents.

Question #1- if I decide to use polyeurathane should I use wood conditioner first?

Question #2- What is the difference between varnish, laquer, and polyeurathane?

I am leaning toward EF water based polyeurathane today as the finish, but it is a daily change of heart so far on what to use. Anybody finish a maple crib and really happy with what they used?

Oh yeah, I do not have spray capabilities and would like to rub the finish on unless brushing offers some sort of benefit.

[Bob Nieman]

Very darn new myself. Without answering your questions I have a comment anyway :)

Boiled Linseed oil (BLO) sure does make maple look nice, especially if it has some figure. Let it cure and then apply your poly (although a weak coat of shellac over the BLO is probably a good idea if you use the waterbase poly (see other posts in this forum))

BLO will definitely give it an amber cast though. From what I have heard (but not tried) the water based poly is a good choice if you want to avoid darkening the maple. BLO is really easy to apply.

A rubbing poly is just thinned down. Easy to apply, but takes (a lot) more coats to build up a coat. You can easily make your own (don't know about the water based variety though)

And now the experts can answer your actual questions....

[Scott Parks]

Jim,

I recently went throught the headache of working with maple. I found that it doesn't stain well. Very blotchy. I tried everything from Minwax, to benite, conditioner, and alcohol dyes. My conclusion.... Leave it natural. I am in the process of finishing another maple vanity, and have thus far rubbed on a very light coat of BLO. This did not amber it very much at all, and it brought out the natural beauty / pearlessence of the grain. I will be sealing it with Target Coatings Emtech sealer and then a coat of semi-gloss water base poly this week....

So, to answer your question... I don't feel it should be conditioned if you are not staining it. If you plan to stain it, then yes, but it will still have some un-eveness. But leave the natural beauty of maple alone! Once cured, I believe most finishes would be safe for crib use, especially waterbase...

For those that want a whitish wood to stain, use alder or poplar, but not maple... IMHO...

[Scott Parks]

Newbie here so please forgive what I will call innocence.

Question #2- What is the difference between varnish, laquer, and polyeurathane?


OK, I hope this is accurate, but I'm not an expert. (disclaimer)

This is a tough one. Basically all are finishes:), they have different charicteristics, but in the end, do the same thing, finish wood. Varnishes are oil based, thinned with mineral spirits. Laquer is thinned with Laquer thinner, more amber and brittle, I don't think it is UV resistant and, it smells funny:D. Over time, sunlight will crack Laquer, but it is easily repairable with another coat of Laquer. Poly's are blends of whatever, man-made chemicals and plastics and can be either water-base or oil-base.

Poly's are the most popular, and I think are often refered to as Varnish. Though, I beleive Varnish is still a different finish??? Each has it's niche.

Check out the recent issue of Fine Woodworking at your Library or book store, there is a breif article about oil finishes and their characteristics. (there wasn't enough info in that issue worth buying, though).

[Jim Becker]

Oil-based varnish comes in three general types based on the resin used to make it...polyurethane, alkyd and phenolic. ALL are varnishes. By definition, an oil-based varnish is a combination of resin, oil and solvents that are baked together (polymerized) so that they form a crosslinked substance. Once they are cooked at the factory, the individual components are no longer what they were when the mixture was started. Each product has different properties for hardness, color, cure time and "durability" (see my original post on THAT subject from when this forum started) based on the ingredients chosen to make it.

Polyurethane varnish, while the most available in the mass market is not always the best choice. It's abrasion resistance and chemical makeup also means it's a "softer" (a relative term...) surface that is sometimes perceived as being less clear and more plastic like. It will not rub out as nicely as a good alkyd varnish (such as Pratt and Lambert #38 or Sherwin Williams Fast Dry Varnish) or phenolic varnish. (such as Waterlox) Varnishes based on BLO (linseed oil) tend to be darker/yellower than those newer products based on soya oil. (P&L #38) Polyurethane also has trouble sticking even to itself which is why you must lightly sand it between cured coats and avoid using wax-containing products, such as regular shellac, under it. (De-waxed is fine) Honestly, in MOST situations, you will be hard-pressed to tell the difference in "durablity" between poly and either an alkyd or phenolic varnish and the latter will often look a lot better on the wood.

Varnishes are also "reactive" finishes that cure chemically in layers. In that, you must be careful when "finishing the finish" that you don't sand through layers noticably...something exacerbated with polyurethane that is not properly prepared for and applied correctly. There are always layers with varnishes. Varnishes are usually brushed or wiped on. You can spray them, but the slow dry time can make for a very sticky shop relative to overspray, so most folks who understand that don't spray varnish.

Lacquer is a whole nuther animal. It's an evaporative finish that also will fully disolve into any previous coats. (Shellac is similar in that respect) In this respect, you end up with a single layer of finish that "finishes" well with rubbing and buffing. But the solvents used with lacquer are quite dangerous and it's a requirement to use proper safety precautions when using them, including both personal protection (organic vapor filtration mask) as well as spraying only in a safe environment...never in your house. Those solvents are not only noxious, but also explosive! Lacquers are generally sprayed as they cure very, very quickly, but there are a few brushing formulas available, such as Deft.

Water-bourne versions of all these products are largely based on acrylics with some other resins added to change certain properties. For example, so-called water based polyurethane does have some poly resin in it, but it's still an acrylic product. It also does not cross link nearly as well while curing as it's oil-based cousin, so it may not give the same "durability" (again, a relative term) on the same project. That said, the world is quickly moving to water-bourne products for safety reasons and they improve every year. In general terms, they will perform well for most folks in most situations. And...they are easy to clean up after and apply. Always a nice thing. Some still don't have the "warmth" that their oil-based counterparts do, however, so some modifications of the finishing regimen are often called for to restore the look using tinting, toning or glazing, depending on the needs of the project. I pretty much exclusively use water-bourne acrylic lacquer for furniture projects that require a good duty cycle, but still do the BLO and shellac first to bring out the color and beauty of the wood first.

Oh, and "wood conditioner" is just another way to take your money. Not necessary under varnish and not necessary for coloration if you use the right products and techniques. Same goes for "sanding sealer". The only "sanding sealer" worth anything is lacquer sanding sealer under the same brand lacquer. The increased solids help you get a really smooth surface quickly, but because of what I explained above, all that lacquer will bind together (burn in) so that it's a single layer in the end. "Sanding sealers" under varnish will actually decrease the durabilty of your finish and may cause flaking...they use searates which make for a very soft layer under a harder layer. Whack that with a hammer...or your shoe...or a dinner plate...and you'll be more likely to damage a finish noticably.

[Jim Benante]

First I want to clarify that I really like the look of the maple as it is and want to avoid too much coloring. I guess a mild darkening and grain amplification would be OK, but not too much.

Jim-Have you used the water-bourne acrylic lacquer of the brush on variety? I don't have the capability to spray. What brand do you prefer? I think I read you like Target on another set of posts. Do they have the brush on variety.

When first applying BLO and then shellac is the color change dramatic on maple? I suppose I could do a really light coat of BLO and then a dewaxed blonde shellac and avoid any major changes. Is this correct?

Thanks for the help Jim, Scott, and Bob.

This forum has helped me enormously get up and running with tool research and learning techniques.

[Jim Becker]

Jim, Target now does have brushable materials. Contact them for more details. Nice folks and great products. That said, consider investing in a nice HVLP conversion gun, like the Wagner that I use (see my website for a review) to begin spraying water-bourne finishes. They are relatively safe to do this, even in a home-based shop with reasonable precautions, since they are low- or no-VOC and have a smell that is very much like latex paint when you are using them. Spraying bigger projects will generally give you a nicer finish faster than brushing, etc.

[Scott Parks]

First I want to clarify that I really like the look of the maple as it is and want to avoid too much coloring. I guess a mild darkening and grain amplification would be OK, but not too much.

Jim-Have you used the water-bourne acrylic lacquer of the brush on variety? I don't have the capability to spray. What brand do you prefer? I think I read you like Target on another set of posts. Do they have the brush on variety.

When first applying BLO and then shellac is the color change dramatic on maple? I suppose I could do a really light coat of BLO and then a dewaxed blonde shellac and avoid any major changes. Is this correct?


Jim,

I'm out of town till Wednesday, but when I get back, I can snap some pictures of natural maple vs. a light rubbed coat of BLO. The coloring difference is only slight, and it still looks great. As far as yellowing, the natural maple will age slight yellow anyway. Before I milled my lumber, it was a little yellow, and after fresh cuts, it became whiter.

On a side note, I brushed Target on my kitchen table. It doesn't lay perfect. I had to build up several coats, and wet sand it flat. It was better suited to spray. If you brush it, make sure you spend the money for a very high quality brush. It WILL make a difference. I have recently bought a Porter Cable HVLP gun from Amazon for $69. The gravity feed cup makes it awkward to handle, but for the price, it's a great starting point for spray finishes. Brushing = slow, spray = fast....

[Ken Garlock]

Jim Becker, thanks for your erudite posting on the different varnishes. I learned a lot from it. Let me suggest that you also have it placed in the articles section for future reference.

[Dennis Peacock]

Another option....IF...you want to add color to the maple is mix in some alcohol dye with some "dewaxed blonde" shellac and rub or spray it on. Don't try to get your exact color all in one shot with this application. It's best to apply a couple or even 3 coats to reach the color you want. By mixing the alcohol based dye with the dewaxed shellac, you get color IN the finish instead of splotchy color in the wood.

The other option is to use an alcohol based dye to color the wood and then apply your topcoat of choice. The dye will give you a more even color in the wood and greatly reduce the splotchiness of the color.

Experiment with a scrap piece to include your choice of topcoat to see if that's the finish and color you desire. It's taken me 1 week to achieve the color and finish I've wanted on a piece before and I'm very glad that I took the time to experiment before applying something to the real piece. If you can afford the time, take the time to experiment / learn about the finishes and small scraps work just as well as a large piece to see how it all works out for ya.

[Jim Benante]

Jim-

Thanks for all the info. I've read many of your posts and you always provide excellent inofrmation in a concise way. Thank you.

I guess at some point I'll need to bite the bullet and get a spray system going. This is my first six months of woodworking and I have spoiled myself so why stop. I might have a few friends of friends who have spray equipment so maybe I can test theirs out before taking the plunge. It wouldn't be too bad to just buy a gun, but I need a compresor too. Any advice on minimum specs for a compressor to be used for spraying and maybe other uses like sanding?

I know the wagner gun says at least 1.5 hp.

Scott- I look forward to the pics.

Take care,

Jim

[Jim Becker]

I know the wagner gun says at least 1.5 hp.

Any time you see a specification for "horsepower" relative to compressors...ignore it. It's irrelivant!! What you need to look at is the SCFM requirment for the tool or tools you want to use...sustained cubic feet per minute of air flow at the required input pressure.

IMHO, you should invest in a compressor that has at least a 20 gallon tank, if not 30 gallon minimum. Units in this size will run on 120v power, although you really should have a dedicated circuit for them as they still draw a lot of amps while running. The larger tank means the unit will cycle less. The less cycling, the less noise and the less moisture introduced into the air supply...which, by the way, you need to remove with proper filtration when spraying. Personally, I moved to a 60 gallon unit (240v) last year and it's greatly improved my air situation in the shop. It will also handle anything I intend to throw at it. (I have a really small portable compressor for running nail guns in the house, etc.)

There actually isn't a huge price difference between one brand's 30 gallon 120v compressor and the same brand's 240v 60 gallon compressor, either, so much of the decision is based on power supply and space. If you have little space, a 20 or 30 gallon horizonal tank will work just fine and can be tucked under a bench somewhere if necessary. And oil-ed compressor generally is a better idea and product than an oil-less, although there are some newer units that seem to have at least solved some of the noise issues with oil-less designs. For longevity, I suspect (un-scientifically, of course) that oiled compressors will still last longer.

[Bill Neely]

I guess at some point I'll need to bite the bullet and get a spray system going. ..............................Any advice on minimum specs for a compressor to be used for spraying and maybe other uses like sanding?


Jim

Hi Jim,

I just tried spray finishing for the first time last week and I was really pleased with how it turned out. I'm never going back to a brush. Just to give you an idea per air consumption: my compressor is rated 8.1 CFM at 40 PSI, my gun 13.2 CFM. The compressor ran less than half the time when I was spraying parts, i.e. cabinet doors, shelves, etc. The only time it ran continuously was when I sprayed a large cabinet back (~15 square feet) making passes in both directions. Something that large is probably as much as I can spray without waiting for the compressor to catch up. I used Fuhr #355 acrylic varnish on maple.

Bill