Stain in wood furniture

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Manalto
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Stain in wood furniture

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Recently I bought a gateleg table (I probably paid too much, but it's square and most gatelegs I've seen are oval.) with a finish that needed restoration. The seller identified the wood as maple, but I'm not so sure. The table is, however, heavy for its size. In addition to the compromised finish, there were some black marks in the wood. I've removed much of the varnish and sanded to a mostly-uniform appearance except for the black marks which remain (there are more than shown here). I'm reluctant to continue sanding, not knowing how deep the stain goes. I have it in the sun in case that will bleach it out. Can anyone identify or make a guess at what this stain is? Suggestions?

ImageGateleg stain by James McInnis, on Flickr

ETA: I changed the heading, realizing what 'furniture stain' also means.

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Gothichome
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Re: Stain in wood furniture

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Manalto, I bet Casey or Al will have a solution for you.

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Re: Stain in wood furniture

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phil
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Re: Stain in wood furniture

Post by phil »

if it is a spill stain then wood bleach might help but you might need to treat the whole top or you'll see a division where you used it. you could try to wet it and then use a stronger concentration solution in the area of the stain but be aware if you just do a local application of wood bleach it can leave a hard line as it will affect the coloration of where it is applied

This might be a natural defect in the wood and in that case it might run deep into the wood, and the furniture maker may have hidden that defect in the wood finishing. You might know which it is if you remember if there was damage from plants and things on the original top. If it's just surface you could break out the hand plane and take more off and then sand since it's solid wood. I have definitely seen marks like that in raw new maple though. look under the table , if you see it there that would mean its in the wood and a natural defect and not just on top. the stain appears to cover not just one board so that probably means it is a surface stain.

if you want to plane it I'd take the legs off and clamp it to a bench so you can work on something that isn't wiggling about. youll want a long smoothing plane not a jack plane. You could use a coarser paper with a belt sander , that might be easier for you but may also leave an unflat surface if you aren't careful.

you could hide it somewhat by using a lacquer with toner, but if you do that go in very light even coats and watch you dont' get drips from the nozzle when you spray it on or you'll be wiping it off to start over. but you might be able to go a bit lighter with the toner in that area to try to blend it. if the top is free of rails and whatnot it might be possible to run it through a wide belt sander. You won't have one but a joinery shop would perhaps do it for a fee.. a machine like that can take the top down in short order and do it evenly.

https://www.scmgroup.com/en_GB/scmwood/ ... anders.870

Phil

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Manalto
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Re: Stain in wood furniture

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Thanks for the suggestions, Phil. I was reasonably sure it wasn't natural because, as you observed, it continues from one board to the next. Not having wood bleach on hand, and not wishing to bleach out the little character that the wood does have, I opted for chlorine bleach, which will remove dye and mildew stains but not alter the color of the wood itself. No improvement.

Sanding the wood has made me realize that this the type of maple that most likely comes from a pine tree. Because it's not a fine piece (I did pay too much), I got more aggressive with the sanding and the stain is now gone. The surface is a little wavy, but not so much that it would tip over a glass or spill your soup.

Now that I've learned it's probably pine, I'm going to refinish only the top, using my favorite finish, Arm-R-Seal, and at some point later on when I know what color to use, paint the legs.

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Re: Stain in wood furniture

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lol I picked up a maple table on the weekend. someone put it out by the curb and a friend needs one. upon closer inspection I think mine is from a particle tree ;-) so at least yours is wood !

chlorine bleach is only the same in name, wood bleach is Oxalic acid. You should be able to get it in the box stores it might be sold as "wood brightener"

I believe the same chemical is used in dying wool, as a "mordant" which is a chemical which "fixes" the die, meaning makes it permanent.

rhubarb has a lot of oxalic acid in it. My mom used to be really into natural dies for wool as she was a weaver and spinner. I can renumber her boiling down rhubarb leaves and all sorts of different plants. now I can sort of piece together why she did that.

I got mine from Mohawk finishing supplies and it came as a paint can full of white powder.
If the table is a bit wavy and you don't want to plane it you could perhaps try to board sand it , you can glue a full sheet of paper to a flat board and sand with that so it can only take the high spots.

if you know it's a bit wavy and dont' want to mess about I'd pick a less glossy coating. you can always do a clear coat of Matte or semi gloss over your other finish so long as it's compatible. that way the waviness wont' be too obvious.

If I spray stuff with lacquer, because I don't have a spray booth I sometimes get a little dust or runs. what I like to do is let it set up good and then I use fine steel wool and "wool soap" its a special slippery soap for this purpose. some use a potato sack and some pumice to do the same. especially with antiques they look funny if they have a showroom shine on them. Knocking back the sheen usually makes the refinishing look more natural.

might be difficult now to find a potato sack that is actually still made with burlap. I dont; know if they were originally jute or hemp or what but you get the idea I'm sure. Makes me wonder where all the burlap trees are ;-)

here's the wool lube product, you might even try dish soap to see if that would work in a similar way. It's like wet sanding with wet or dry paper it makes it cut much better and has the effect of making a smoother finish with the same grit or in this case, the same coarseness of the wool.

http://www.mohawk-finishing.com/catalog ... ictNbr=243

if you put polyurathane on the top you wont; have to worry so much about water or plants and such. I know it isn't the favorite finish I'd never use it on anything valuable but sometimes it's ok for a kitchen table that you want to wet wipe often and if you want to do the wool lube thing with that you can actually use the same thing that they use to thin the poly - paint thinner! this caught me by surprise because one day I'm adding it to the finish to thin it and then the very next day wet sanding with paper soaked with the paint thinner.

the reason you can get away with it is because the poly hardens by a chemical reaction called polymerization. The reason why you'd want to use that is because the poly takes a week or two to harden up, and if you attempt to sand it it balls up on the paper as it's still too soft to sand. youd be frustrated and throwing out your sandpaper every three strokes. the paint thinner stops it from balling up on the paper. this means you can do a little sanding to knock out the dust etc and continue to do more coats while the poly is still soft. It knits together if you get the coats down in succession but if you let it cure and recoat then the layers of poly only stick to each other by mechanical means. that's ok that's how most paints stick. That's a mechanical bond not a chemical bond,, plastic paint might knit chemically much like the coats of poly.

shellac and lacquer are quite diferent because with those finishes subsequent coats melt in to the previous coats and "amalgamate" most paints also do not amalgamate. one exception is lacquer paint.

a little OT but I was moving stuff around the basement and came across a old 78 record that was broken. I snapped it into little pieces as I want ot try and experiment. I believe you can just add lacquer thinners to that and create your own black lacquer paint. its really no different than mixing your own shellac from cookies and chips or pucks.... free black paint made from broken records ;-) I thought it was a pretty resourceful idea and sometimes they just come your way or you may see scratched up ones at the thrift that really have no marketable value. anyway Ill get back to that experiment,,, and I guess we should return to the thread about the table..

Phil

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Manalto
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Re: Stain in wood furniture

Post by Manalto »

Interesting experiment with the old record!

phil wrote:
chlorine bleach is only the same in name, wood bleach is Oxalic acid. You should be able to get it in the box stores it might be sold as "wood brightener"


I probably didn't make my comment clear above. Oxalic acid bleaches the wood; chlorine bleach takes out (some) stains, leaving the color of the wood intact. I tried the chlorine bleach in the hopes that it would remove the stain only. No dice, so Plan B was aggressive sanding. I'd rather have the character of stained wood than white, grainless wood, which is what would happen with wood bleach. And frankly I wouldn't want to invest a trip to the store and the price of wood bleach for this piece anyway. It's just not worth it especially when I can simply sand off the stain.


phil wrote:If the table is a bit wavy and you don't want to plane it you could perhaps try to board sand it , you can glue a full sheet of paper to a flat board and sand with that so it can only take the high spots.


Upon closer inspection, the low point is next to where I sanded down the stain, so there is some warping history going on. It's fine for what it is. I'm going to use it in the kitchen.

phil wrote: I'd pick a less glossy coating. you can always do a clear coat of Matte or semi gloss over your other finish so long as it's compatible. that way the waviness wont' be too obvious.


I'm going to use Arm-R-Seal which is a blend of tung oil and polyurethane (something like that) and has the best characteristics of both. It leaves a nice, subtle finish (like tung) and has the toughness of polyurethane. I've used it on good cherry furniture on which people are likely to set a drink - if carefully and cleanly applied and buffed with 0000 steel wool between coats, it looks great. I'll use the 'satin' finish on this table.

phil wrote:might be difficult now to find a potato sack that is still made with burlap.


Years ago, I was delivered a stone fountain that was packed with burlap bags. The bags had been previously used to ship cocoa from Ivory Coast. (They smelled good, as I recall.) I saved them all and still have a stack of them.

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Re: Stain in wood furniture

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I have an old oak table in my kitchen. My girlfriend likes making bread , Im not going to discourage that ;-) but it's worn off the shellac. i wouldn't use poly and I have heard some tung oil is food safe , so maybe some isn't. Its an antique so poly is out of the question. If re do it in shellac I can. If I put a hot cup of coffee down on it , it sticks to the shellac. maybe I jet need to make her up a big breadboard and put it away and use it just for that. when you work with the dough its nicer if it isn't sticky like poly would be.. as is it's worn through. I would normally just use danish oil to revive it for now but the finish being food safe is a bit more of a concern if you are using it for rolling dough than just eating at. Ive got a tabletop made of laminated strips of fir so maybe I could plane that to bare wood and have her use that. It heavy but maybe a 3 foot square would be ok.

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Re: Stain in wood furniture

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Even though I don't make bread (except for the occasional pizza) I was curious about this, too, so I did a little poking around in breadmaking forums. I found out that kneading boards are preferably hardwood, for durability and sanitation. One baker mentioned that she liked the small amount of "tooth" that hardwood has, claiming that it aided in the kneading process. Oak, although it's a hardwood, was mentioned as being undesirable because of its large pores, which can harbor bacteria. Fir was listed among the less-desirable softwoods. I take this information with a grain of salt because people have been making bread for thousands of years, and I'm sure they used the surfaces available to them, whatever the material. Conditions were not operating-room sterile, I suspect - the standard that prevails today. That bacteria probably did more good than harm. Bamboo (technically a grass) was mentioned as well. I have seen warnings about bamboo cutting boards saying that toxic adhesives are sometimes used in their construction, so have steered clear of using bamboo laminates around food.

Marble was also mentioned as particularly good for pastries because of its tendency to stay cool; the jury appears to still be out regarding its suitability for yeast breads, which benefit by warmth. Other stone surfaces - enormously popular today - would fall into the same category. A few people liked Formica - their existing kitchen countertop. Those who mentioned a preference for plastic surfaces are not my kind of people and will henceforth be ignored.

A good suggestion (I thought) for a kneading board, customized to the size of a tabletop, is to make it slightly larger than the table and attach a lip underneath on both sides to prevent the board from sliding around during vigorous kneading.

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Re: Stain in wood furniture

Post by phil »

thats a good idea of putting two lips on it , I had envisioned a hook on one side but that makes more sense actually, it could slide on from the end.

maybe mahogany would be ok. i wondered about the glue they used to make my laminated top. I don't know what it is -a dark colored glue.

I have some stone look alike laminate that I used on my counters and some left over , I guess that might be ok too, it isn't' exactly smooth although it isn't' porous either. I'm not big on plastics but I like formica. stone looks great but I would hate it. It sucks the heat right out of my nice warm cup of joe ;-) I just don't like the hard feel of stone. sliding a cup or plate is like running your fingers down a chalkboard. I'd prefer a worn out old table, I just find it nicer to touch.

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