Bleach or acid solution may help ligthen water stains

Q. I have a room addition to my house, which is paneled with cedar that was not treated with anything.

The roof was shingled, but the flashing against the original house was faulty and resulted in gradual wetting of the interior paneling.

At the extremities of the water stains, as they dried, a very dark coloring has occurred. Do you know of any method or product that can be used to minimize or eliminate the dark coloring?

A. I hope that the flashing has been repaired.

First try to lighten the dark stains by applying a solution of three-parts water and one-part Clorox bleach with a new or thoroughly cleaned paintbrush. Use the solution sparingly so as not to have it run down and cause unsightly streaks.

If this is not successful, get some oxalic acid crystals from a paint store and mix them in hot water to saturation (until some crystals are no longer absorbed). You will only need a small amount of oxalic acid.

Oxalic acid is very caustic, so use great caution handling it. Wear protective clothing and eyeglasses, mix the crystals in a glass or plastic container — do not use a metal container or metal tools. Apply the solution as carefully as mentioned above — feathering the area to be treated with a barely wet brush.

Q. We have a real antique cast-iron farmhouse sink in the brick farmhouse and farm we purchased in 1945. The farmhouse was built in 1863, but the sink is even older, having been used in an earlier wood house. The sink is approximately 2-feet wide by 4½-feet long. It has had daily use for all kinds of washing and it has been wiped dry after each use. Once dry, it was rubbed with beef suet to protect it from detergents, vegetable and fruit juices, etc. More recently, we have used Johnson’s Baby Oil, having read in a Vermonter’s cookbook of the success she has had with it on her beloved iron sink.

The Ivory Soap used in the various washings in the older days seemed to protect the sink from detergents, but now it appears as if the sink is less protected and the baby oil treatment has very little lasting effect.

If you know of another way to protect the sink after each use and after it has been thoroughly dried, I would be happy to try it.

A. The Kohler Co., manufacturer of cast-iron sinks, sells a nonabrasive Cast-Iron Kitchen Sink Cleaner that has wax in it for protection of the surface after use.

Q. We have a double bowl, undermounted Corian sink and Corian countertops in our kitchen that were installed more than 20 years ago. The countertops are still in very good condition. However, the sink is stained brown. I can get it reasonably clean by filling it with a bleach solution, but after a few days it is brown again.

I would like to replace the sink with a stainless steel or other type. However, it seems that no contractor is willing to touch it without replacing all the countertops as well. The concern they have is that the countertop will crack if they attempt to remove the sink.

While I would love to replace my countertops, that is an expensive option that seems unnecessary. Do you have any suggestions for restoring the Corian sink surface to remove the brown stains? Are there ways to remove an undermounted Corian sink from the countertop that won’t risk damaging the countertop?

A. Separating the Corian undercounter sink from the Corian top is a job for a certified DuPont Corian fabricator. It requires a specific tool; it is difficult and messy to do, creating a lot of dust — all reasons for which it is best to take the top and sink assembly to the fabricator’s shop — an expensive undertaking.

Corian is a solid surface material that does not let stains penetrate the material; any visible stains are on the surface and can be removed. I suggest you do not remove it, but solve the recurring brown stains, which are likely caused by iron in your water. You may want to have a water specialist analyze your water to remove the iron in it.

Here are several things you should consider doing to remove the stains, in order of increasing aggressiveness:

Ÿ Do what you have done before;

Ÿ Try removing the stain by rubbing it with Zud or Comet, using an aggressive Scotch Brite pad.

Ÿ Sand the stain using 150-grit sandpaper to start, and finish with 220-grit sandpaper.

According to my certified DuPont Corian fabricator friend, you can’t hurt Corian. All of our kitchen countertops are white Corian, and I would not use anything else. The only rule, as for all spills, is to wipe them up immediately before they have a chance to dry.

Q. I have two questions:

Ÿ Could you please advise if there are any dehumidifier manufacturers who currently have machines that do not run constantly? I recently had to replace the old unit, on which I set the dial to the number (humidity) desired. The unit ran, then shut off. I replaced it with a Hisense unit and read the directions thoroughly. After I set the controls to 60 percent and low fan speed, the fan ran constantly. I thought I missed something and called the company’s hotline and was informed that these new units are set to have the fan run constantly and cycle the compressor. I asked how many watts does the running fan draw and was told 20 watts (no numbers are furnished to the consumer in the operating manual). Upon receipt of the electric bill for the first month I used it, I noted that my usage was up substantially.

Ÿ Would you please revisit gutter guards? My roof is a mansard, and no helmet type will work, as the rain will just bounce off due to the almost vertical angle of the roof into the gutter. I am considering foam cell. The other screen types wouldn’t last long, as icicles off the dormers would make nice holes in them in winter.

A. The best I can tell you is that we have a Danby Designer dehumidifier, which comes on only when the relative humidity in the space gets higher than the setting we’ve selected. There must be others, but I have not researched them.

I have tried quite a number of gutter guards over the years and have yet to find one that functions satisfactorily in the long run. When you check out the various types, each one claims that it is the only one that works, and it denigrates all the others by showing them in their state of disrepair. But as you check out another, you’ll find that the denigration continues with similar demonstrations of the others’ failures.

I have come to rely on wider commercial gutters and downspouts, and seasonal checking to see if they need cleaning. The most important feature of commercial gutters and downspouts (which can be installed on residential gutters) is the cross-section size of the downspouts, which is twice that of residential downspouts and far less susceptible to clogging.

Q. Do you know of an outdoor varnish more durable than Minwax Spar Urethane/clear satin?

Our front door faces west where the sun beats upon it. The door is a Feather River fiberglass door, and it’s holding up well. However, the wood brick molding and kick plate are a problem. The Minwax Spar varnish does not hold up.

A. Try a marine varnish. But first, you’ll have to remove all traces of the existing varnish down to bare wood.

Q. I have a question regarding round shut-off valves for washing machine hoses.

In your column, you have mentioned that one can buy and use a “Gordon wrench” to help turn an oval shut-off valve. I bought a Gordon wrench on your advice years ago, and it works great.

My new situation: I have two round shut-off valves (hot and cold water) for my clothes washer and they have not been turned off for more than 30 years. The clothes washer is in the kitchen area so it is not subject to extreme temperatures. I would like to replace the two hoses just to be safe. Is there a Gordon wrench for round shut-off valves? I hate to use a large pliers or a similar tool to try to turn the valves because I am afraid I will break the handles (or the stems or whatever else can go wrong!).

A. The Gordon wrench only comes with two oval valve sizes. Round shut-off valves are much stronger than the pot metal of the oval valves. Try to free them gently, using a pair of channel locks.

Consider also changing these valves to a single-handle shut-off valve to turn the water off easily after each use. This eliminates the pressure on the hoses.

Helpful advice from a reader: Following up on a reader’s question on how to remove dark stains on gutters, this is the solution from another reader:

“Last spring, I also faced this problem and tried several products (nearly everything we had on hand). I finally used something that I often use in other ‘hopeless’ situations: brake fluid.

“I use brake fluid extremely sparingly — a 12-ounce bottle lasts me for several years — but there are a few situations where nothing else works, like fiberglass resin on the hands; I always use hand moisturizer afterward. It took a few tablespoons and a lot of paper towel and elbow grease but I was able to clean about 40 feet of gutter over our deck. It has remained bright, and I can now use a milder cleaner to maintain it. I enjoy your column.”

Ÿ Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. Write to him in care of the Daily Herald, P.O. Box 280, Arlington Heights, IL 60006, or via email at henridemarne@gmavt.net.

© 2013, United Feature Syndicate Inc.