Archive for the ‘stain removal’ category

Quick Tip #31 – Paint Over That Water Stain

September 15th, 2014

Let’s say there was a leak in the drain for an upstairs bathroom that left a brown stain on the drywall below. No problem – you painted it with latex paint left over from painting the ceiling, and at first it looked great. But a week later the stain started to bleed through the paint, and eventually it looked just as bad as before. Now how do you fix it?

Primers and stain killers need to be applied over stains before you use latex paint. Typical latex paint just doesn’t have the capacity to cover serious stains and water marks. Primers and stain killers have special binders and covering agents that can block stains and provide an excellent base for latex paint.

What is a good primer? For interiors, KILZ and BIN are excellent stain blockers. Where there is a water stain, remove any loose material, patch, and then apply the primer. If the drywall and paint are solid, just paint over the stain. BIN actually contains shellac; professional painters have used this stain-killer for many years.

Many manufacturers make specialty primers that work well to cover most stains.

M066C - Paint vs. Primer_300dpi

Candle Soot: Shadowing and Ghosting

April 13th, 2013


Two years ago, we installed a new roof with ridge vents. Recently, we have noticed shadows on our ceilings in places where the roof trusses run. The house has cathedral ceilings as well as flat ceilings, and these “shadows” show up in all rooms. Also, along an exterior wall in our kitchen, we can see (from end to end) the outline of the roof truss, as well as vertical markings of studs. The markings in the ceiling and the walls look like someone lightly penciled in shadows of the trusses and studs. Can this be a result of the ridge vent that was cut in the roof?



What you are describing is textbook “shadowing” or “ghosting ” from candle soot. Does someone in your family burn those nice aromatic candles in glass jugs? Those are great soot producers.

M049 - Candle - Soot Generator


Candle soot is about as heavy as air. It moves throughout your home, aided by the forced air furnace. Outside walls and attic ceilings have plenty of insulation, but there is much less insulation on the framing edges. As a result, framing edges and fasteners are slightly cooler than the surrounding drywall.

When the air moves across the cooler surfaces, it slows slightly and deposits soot. The dark soot stains outline the framing with a shadowy or ghostly appearance.

So, stop burning candles! Or at least burn only very high-quality candles, and keep the wicks trimmed to 1/4 inch or less. Don’t burn candles in jugs – their combustion is starved of oxygen, so it produces lots of soot. You can find more information at in the Free Articles section; look for the article, Soot, Ghosts and Ugly Stains.

M050 - Candle - Trim Wick


Water-based Polyurethane Over Oil-based?

June 21st, 2011


Is it OK to use a water-based polyurethane such as Minwax Polycrylic over an interior door surface that had previously been finished with oil-based? Minwax says it’s OK, but the lady at the home improvement store said no. Could you please break the tie?



In most cases, it is OK to use a water-based polyurethane over an oil-based finish in good condition. You should remove grease, dirt and wax by scrubbing the surface with a wood prep/cleaner/de-glosser, or mineral spirits and synthetic steel wool. Then “roughen” the surface finish lightly with medium or fine-grit sandpaper in the direction of the grain. You want to remove the gloss from the finish. Remove all the dust with a vacuum or tack rag.

Apply the new water-based finish per label directions. The application is typically done with a lint-free cloth and several coats are recommended. The advantage of the water-based finish is ease of use, quick drying, no odor, and easy cleanup.

Zar-ULTRA-MAX-Wood-StainOne word of caution – read the label carefully and follow the specific instructions. Some of these water-based finishes are not for use over lacquer or shellac. Spray lacquer is commonly used on new furniture and in new construction. A great finish to try is ZAR brand ULTRA Max – a waterborne oil modified polyurethane.

Top Coat Finish Touch-Ups

April 6th, 2011


I own a house that was built about 8 years ago. Recently, I was using alcohol to clean off some greasy spots on the oak cabinet veneer sides and solid-wood door near the stove, and apparently the alcohol was strong enough to remove some of the clear-coat top finish. I don’t understand why, because I thought alcohol would not remove lacquer or polyurethane finishes. I was guessing that the top coat finish could be either lacquer or polyurethane. What kind of top coat finish can I use to touch-up the top coat that blends in with the surrounding finish?


Most of the clear finishes used in modern construction and shop-made cabinets are a spray lacquer that should not be affected by alcohol. Lacquer is used because it is a durable finish and dries quickly. Either your finish is shellac, or somehow compromised.

I suggest you try a clear, wipe-on oil finish to renew the surface. Minwax Antique Oil Finish and General Finishes Royal Finish are two good options. You may need to go online or to a woodworkers store to find these finishes. They can both be carefully applied over an existing finish.

You can’t use a urethane or polyurethane because it will not bond to the existing finish. If you can confirm that the finish is lacquer, you could use a lacquer, but application is an issue and almost impossible for homeowners. We just can’t spray the lacquer.

With the wipe-on oil, make sure the surface is very clean, then wipe on a thin coat with a rag dampened in the finish. It will be a thin coat that will dry quickly. Add additional coats to increase the gloss.

As with any finish, test a small area first. With a little luck and an artist’s flair, you can just touch up the affected areas or the panel without working on the complete cabinet.

Black Discoloration on Wood Windows

July 13th, 2010


We have a black discoloration occurring on the wood part of the windows in our house. Do you know what it is and how to get rid of it? The windows are double-hung and the house was built in 1995. I assumed it was mold and moisture-related because I noticed it first in the bathroom, but now I have found it in small patches on other windows. I have tried many cleaning solutions including TSP and a bleach-water mix, but none seem to work. It occurs both in winter and summer, with windows open or closed.


If the stains are a dark discoloration that cannot be removed from the surface, you have water damage in the wood. If the TSP removes the stain it may be dirt or mold. Once the surface finish is damaged by water, the water will discolor the wood. If the finish is gone and you have a dark stain, you have water-damaged wood.

The fix is to refinish the wood by sanding, bleaching, and more sanding. Then stain and varnish back to the original finish. It’s not an easy job. Don’t get too worried about the “mold” word. Issues related to mold have been greatly exaggerated by many folks in recent years. Go to the State of Wisconsin or university websites for accurate information about mold in a home – not testers or contractors who make money on mold.

Light Blue Stains in the Toilet

June 16th, 2010


We have a 7-year-old toilet that has begun showing a light blue color. When I try to scrub the blue stain with a toilet brush it doesn’t come off. We’ve never used those blue tank canisters; we just use liquid bowl cleaner. Do you know why the toilet bowl is stained light blue? I checked the water (in the bowl and the tank) and it is not blue.

I also noticed a lot of black mold inside the toilet tank when I took the lid off. Is it a good idea to use bleach to clean the mold off the inside of the tank and underneath the lid? There is a rubber-type 5-inch ball in the tank. Can I use bleach to clean that rubber since it too has mold on it?


The light blue stain is a strange one. Do you have a private well? If the water is slightly corrosive, I suppose you could get a blue stain from copper or brass in touch with the water. Perhaps it is from a cleaning chemical? I would try to clean the bowl with an acid-based cleaner. Look for the acid cleaner in a plumbing supply or hardware store.

You certainly can clean the toilet tank with any chemicals you wish. Most toilet tanks will have deposits. If you do use bleach, don’t let it sit on the rubber parts because it can damage the rubber. You can remove mold with just detergent and water.

Soot and Sawdust Removal

June 1st, 2010


I think I have soot stain problems in my house after reading about them on your website. I have all-electric house heating, made up of baseboards and storage units. My wife loves her candles as much as I love my woodworking, but both cause dust and soot. Can you suggest a cleaning solution for the ceilings and walls? Also, can you recommend any air filtration solutions to help the problem? Thank you.


The best solution for the soot stains is to stop burning all candles. Well, OK – I do ‘let’ my wife burn a few high quality candles, and she keeps the wicks trimmed to about 1/4″ length. A high quality candle and a short wick will reduce the soot produced. We don’t ever use the nice, smelly candles in a glass jug. They are great soot producers because there is a lack of oxygen in the jug and the scent comes from something released into the air.

Removing the soot is a problem because it is such a fine particle and it tends to stick to surfaces with a magnetic charge. You can try a dry sponge – it’s a large, soft, rubbery sponge that absorbs soot. They are used for fire restoration work and you can find them in larger paint departments. After wiping with a dry sponge, clean the area with a strong detergent using lots of rags and water/detergent changes.

Soot is very hard to remove. When re-painting, prime the surface with BIN to cover the soot. BIN is available in most paint stores and is also used in fire restoration.

There is no filter that will remove soot. For the woodworking dust, I suggest you try to control it at the source. Use a vacuum system with a great filter and seal the woodworking shop from the rest of the house. Seal any heating ductwork in the shop, particularly the return ducts that may suck in the dust from the air. On a forced air furnace, use the best quality paper filter you can find to remove the sawdust.

Improve the Look of Woodwork

May 27th, 2010

I am looking for a product to make our woodwork look better. This includes trim boards, cabinetry (bathroom and kitchen), and the log walls. All I really know about is Scott’s Gold; it looks good short-term, but not long-term. Is there anything better, or maybe different products for different places? Just thinking that I should begin to perk the place up for a spring graduation and a summer wedding.


Scott’s Gold is basically a solvent with a nice smell. It is a wood cleaner. It does not really improve the clear wood finish.

If you really want improve a wood finish, I would consider adding a very light coating of a wipe-on oil finish. I like General Finishes, Royal Finish the best because it sticks to all other finishes, comes in gloss and satin, and goes on with a rag. It is also low odor, dries quickly, and easy to control. Extra coats give you extra depth and shine.

Screen Shot 2014-05-22 at 5.44.45 PMOther options would be a wipe-on Tung Oil or Minwax Antique Oil Finish. The key here is to select a finish that is compatible with the existing finish, and one that will stick with minimal preparation.

For preparation, you need to make sure the existing finish is clean and free of any sticky or worn finish. You can often clean by scrubbing with a sanding eliminator solvent. Unfortunately these solvents are flammable and have a strong odor. You will need ventilation, and you have to follow all label safety precautions. This type of cleaner will also dull the existing finish – good to make the new top-coat stick.

Light sanding may also be required if the finish is chipped or flaking. Sanding with fine sandpaper will dull the surface and remove damaged finish.

When working with cabinetry, you will need to remove the hardware and carefully clean around all handles. The areas around the handles tend to become sticky and dark as the oil in our skin breaks down the finish overtime. For really sticky, dark areas you may need to use a refinisher chemical like Homer Formby – furniture refinisher. This introduces a new level of preparation work as you scrub with steel wool and basically strip the surface of the damaged finish.

Sorry – no easy fix here. On my website, you will find a complete article about refinishing kitchen cabinets in the Free Articles section. This addresses refinishing without stripping.

Kitchen Cabinets – Replace, Re-Face, Refinish or Paint

Dark, Leaf Stains on Patio

April 29th, 2010


I have some dark leaf stains on my patio from last year that just won’t go away. Should I just let it be, or do you recommend something to remove them? Perhaps bleach?


Eventually, the dark leaf stains will go away. Weather and ultraviolet sunlight will get to the stains, but it takes some time. Bleach can be effective with detergent.

If you want quicker action, try scrubbing with a strong solution of MEX. You will find MEX at the hardware store. It is a strong detergent specifically designed for concrete and masonry surfaces. Mix a strong solution in very hot water, then scrub with a stiff brush. Allow it to soak, then scrub repeating several times.

You could also use a cleaner that contains oxalic acid like Zud, wood bleach or a deck cleaner. This will remove the stains, but may also lighten the concrete surface color. You may need to clean the whole patio once you start with an oxalic acid cleaner.

White Stains on Slate After Flooding

April 27th, 2010

We have slate on the floor under and around a portable fireplace. Last winter we had some flooding in that room, and it seems that the water caused white stains to appear on the slate. We tried Lime-Away to no avail. Do you have any answers how we can remove or cover the white stains?


When white stains appear on stone or masonry surfaces it is usually efflorescence (salt and lime stains). The stain is from salt and lime in the masonry materials (grout, block, or concrete), and the stains come to the surface with water movement.

You could try a stronger cleaner. Scrub the area with a strong solution of MEX and hot water. MEX is a detergent that is also used for cleaning masonry. If the stain remains, test a small area with UGL ETCH. This is an acid cleaner for efflorescence. You need to test an area because it may also discolor the slate. Finally, you could go to a store that deals in tile and slate and find a proprietary cleaner for slate or stains.