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Just a couple of warnings about using acetone
It will dissolve or haze many plastics and it will damage most finishes. Just be careful not to splash it around anywhere and drop cloths would be prudent.
Use with plenty of ventilation.
No offense to uncle Bob, but in my opinion, this is one of the major problems with Sears tools — by contracting with manufacturer du jour, you can be left high and dry in the replacement parts department. Sears contracts with XYZ manufacturer to make a tool for them, which they do for a few years. Then Sears moves on to manufacturer ABC. Manufacturer XYZ has no reason to make any more of anything.
I know I can still find parts for my 25 year old Bosch tools.
The other reason is that Craftsman power tools rarely have the quality as the traditional professional-quality brands. Price may be a more important consideration than other features.
Teak can be a problem for some finishes because its oils inhibit the finish from ever curing or reduce adhesion.
One the wood is [stripped,][ sanded, cleaned and ready to go, wipe with a strong solvent such as acetone, or if you don’t have that, lacquer thinner.
As soon as it’s evaporated, apply a light coat of shellac or a shellac based primer such as BIN. After 30 minutes apply a second coat. Let that dry, then you are ready to go. If you are applying clear shellac, I like Zinnser’s SealCoat. While advertised as a universal sanding sealer, it’s simply a 2 pound cut of 100% dewaxed amber shellac.
I do not like stearated sanding sealers. They are soft, don’t have much resistance to water vapor, and if you are applying a clear coat (though it sounds like you are painting), an impact or concentrated pressure creates a fractured sanding sealer that is white and is below all the coats of finish, so there’s not much way to repair without digging it out and rebuilding or stripping and refinishing.
There are several classes of sanding sealers (e.g., stearated, vinyl, etc.) and you have to make sure that your top coat is compatible with the sanding sealer you use. This is not a problem with shellac.
If you are doing a clear coat, shellac also adds a lot of luster and depth to the wood grain (chatoyance.) It really makes most woods come alive. I just loaded an antique writing desk to return to a customer tomorrow. He thought it ought to be stripped and refinished. I spent a few minutes cleaning it and gave it two quick shots of shellac and it looks like a million bucks now.
You can use this to remove black “water marks” from oak.
A common occurrence, explained here:
http://www.baneclene.com/catalog/soilfiltration.htmlThese are called threaded inserts and are readily available at hardware stores. Figure out the size (internal thread). Normally, these are 5/16″ x 18.
http://www.rockler.com/product.cfm?page=362&filter=threaded%20insertIf the leg has enough meat on it, you can insert one deeper into leg. Drill a hole deeper and get a longer bolt, if needed.
Otherwise you can get the next size up and the next size larger bolt.
This is called “fish eyes” and typically comes from silicone oil contamination. The usual culprit is Pledge furniture polish. No amount of stripping is going to get rid of it. It will affect varnish, lacquer, and water-borne finishes the same way.
The best cure is to strip off the fish eyed finish, once again. Sand. Re-stain, if desired. Then apply two coats of DEWAXED shellac. A good choice for this is Zinsser’s Seal Coaat.
Poly will have problems adhering to waxed shellac.
There are whole books written on this subject.
The major steps are:
– Stripping with a chemical stripper
– Drying
– Sanding / repairs
– Staining / coloring
– FinishingI suggest buying or getting this book from your local library:
http://www.amazon.com/Understanding-Wood-Finishing-Select-Finish/dp/0762106212/ref=sr_1_1?ie=UTF8&s=books&qid=1256086009&sr=8-1The finish is only a few thousandths of an inch thick. The depth of the damage will have quite different requirements for a fix.
http://www.popularwoodworking.com/article/Repairing_Color_Damage/Another way to fill scratches is to get some lacquer. Fill a paper cup about 1/2″ deep. Let it sit out for a few days until you have about half the volume or less. You will have a very thick, syrupy lacquer. Using a toothpick, drip and drag lacquer into the scratches. Let it flow out and dry. Sand to level. Repeat if needed. You may need to spray a little aerosol lacquer on at the end to match the sheen. You might also apply the aerosol after dropping in the lacquer to get it to flow out and level.
As with all new procedures, try this out on a practice board first.
Yes, you will need to remove the existing finish. My preference would be stripping, maybe preceeded by a good scraping to remove the flaking parts.
Note that there are different “spar varnishes.” Technically these are “long oil varnishes,” meaning they have a high proportion of oil to resin in their manufacture. This is done to improve flexibility. They are NOT more resistant to water, but less. Consumer versions such as “Spar Urethane” are going to fail in short order. Ship chandlers will sell high quality marine varnishes. These run about $40 to $50 a quart. Plan on putting on lots of coats, maybe six or seven. And plan on regular maintenance of scuff sanding and applying maintenance coat, maybe annually. A recent Fine Woodworking (June 2009, #205) article on exterior finishes is worth a read, too.
