Here’s How to Keep Stored Paint Skinless
QUESTION: What’s the best way to store partly used cans of paint without having them develop a skin on the surface?
ANSWER: Here are several solutions that have worked:
* Store the can upside down.
* Cut a piece of wax paper the same diameter as the inside of the can and drop it down on top of the paint. When you are ready to paint again, simply remove the paper and the paint under it will be ready to stir and use without lumps or pieces of dried paint skin to strain out.
* Blow into the can before you put the lid on it. The carbon dioxide in your breath prevents the paint from oxidizing.
* The best answer we’ve found is to pour a thin layer of the proper solvent for the type of paint onto the surface of the paint left in the can. Use just enough thinner to cover the surface of the paint. Then, the next time you use the paint, simply stir the thinner into the paint. This way, you have no skin formed at all and there is nothing in the can to fish out and dispose of. Besides, most paints will spread much more easily when they are slightly thinned, especially those that have thickened a little as their solvents evaporated during a previous use and storage period.
Adapters Are Needed for Pipe Repair Project
Q: I’m replacing some bad sections of copper water pipe. Can I use PVC pipe for the repairs?
A: Plastic water pipe can be joined to steel and copper pipe by means of plastic threaded adapters. Both male and female plastic adapters are available. One end of the plastic adapter is glued to the plastic pipe and the other is threaded into a fitting or onto a pipe.
When joining plastic water pipe to existing metal piping, wrap the male threads with plastic pipe joint sealant tape. Because plastic female adapters can expand when threaded onto male threads, a better choice is to use a plastic male adapter threaded into an iron or copper female adapter or fitting.
How to Give a Sloping Concrete Slab a Lift
Q: The concrete walk in the corner of our L-shaped house has settled to a slope of 3 or 4 inches. The slope causes rainwater to seep into the crawl space. Can we top this walk with a thin layer of concrete, or will it crumble?
A: You have three choices: replace the slab, top it with a layer of concrete, or lift it up and fill in under it. There are two ways a homeowner can lift a slab. If the edge of the slab is accessible, you can use a pry bar. If the edge is not accessible, or it’s too big to pry up, you can jack it up.
Span across the slab with two 2-by-4s placed on edge. Bore holes through the 2-by-4s and through the concrete slab (rent a hammer drill if need be). Take some threaded rod (known as all thread) and put a spring-loaded wing on the end of each piece. Push the rod through each hole in the 2-by-4s and into the holes in the slab.
Put a washer and nut on top of each rod and thread the nut down. Drive the rod down, with a hammer if necessary, until the wings open under the slab. Be sure to put the nuts on the threaded rod before driving the rod down. Driving the rod will mushroom the threads and make it difficult to thread the nuts on the rod.
Tighten the nuts against the 2-by-4s to jack the slab up. Then pour a slurry of cement, sand and water through the open holes in the slab to fill the void underneath. Turn the rod out of the nuts when the filler under the slab has set up a little. Patch the holes, and the job is done.
Proper Ventilation Helps Reduce Mildew
Q: Although my bathroom has a window, I keep finding black spots on the ceiling, which I believe are mildew spots. I want to install an exhaust fan in the bathroom to increase the air flow. Can I just vent the fan into the attic, rather than run it all the way through the roof? Would the moisture cause any problems to the insulation in the attic? Also, what is a good way to get rid of the black spots?
A: The black spots on the ceiling are spores of mildew. You can get rid of them by sponging the ceiling with a solution containing a chlorine bleach, such as Clorox and water. Allow it to remain for 10 to 15 minutes and then wipe and rinse it with fresh water. Keep the window open while sponging and rinsing the ceiling.
Mildew flourishes wherever it is damp and warm and where there is poor air circulation. Opening the window brings in fresh dry air and helps prevent mildew from accumulating. However, if opening the window daily is not practical, then you should install an exhaust fan.
Don’t vent the fan directly into the attic because it will introduce a considerable amount of moisture into the area. This can cause condensation problems and if the attic is inadequately vented, the moisture can promote rot in the wood framing members.
If you don’t want to extend the fan discharge duct through the roof, you can extend it so that it ends at an attic vent, such as a gable vent, soffit vent, ridge or roof vent.
2 Products Should End Problem of Rusty Tub
Q: Would you know of any chemicals that would clean a bathtub of a fine film of rust? I use Sani Flush for our toilets, but the manufacturer suggests using it only for the toilet.
A: Two products that should work for you are Rust and Iron Stain Remover and Rust Stain Remover. Both are made by Whink Products, 1901 15th Ave., Box 230, Eldora, IA 50627; (800) 247-5102. You should be able to find these products where housewares are sold.
To submit a question, write to Popular Mechanics, Reader Service Bureau, 224 W. 57th St., New York, NY 10019. The most interesting questions will be answered in a future column.