Dear James: I have been trying to clean up and refinish some of the hardwood trim in my older home. I went to the home center store to buy sandpaper, but there are so many types. Which is best for what? — Randy T.
Dear Randy: The sandpaper aisle at the home center store can be a bit overwhelming, sometimes even for professionals. It could be worse, though. If you go online sometime and search on sandpaper, you will find your home center offers less than 10 percent of the overall available sandpaper selection.
It will be worthwhile to do a little research on sandpaper to get a basic understanding of how it works and its uses. The reason there are so many different types of sandpaper is that there are many different sanding tasks.
Selecting the proper sandpaper can cut the sanding time in half and produce the attractive finish you desire. Even for the simple job you are doing, you will need many different types. On some spots, you may want to remove the old finish. On others, you may want to just polish the old finish or do deep sanding to removing scratches.
All sandpaper can be put into one of two categories — opened or closed. Closed sandpaper has a solid covering of abrasive particles. This is ideal for sanding metal or other very hard materials.
But on opened sandpaper, only 40 to 70 percent of the surface is covered with abrasive. The purpose is not to lower cost. The open areas provide room for the sanding dust so that the paper does not quickly clog and become ineffective. This is the type of sandpaper you should be using, especially for the initial sanding of the wood. Wood sanding dust can be quite sticky.
The grit number of the sandpaper indicates the size of the abrasive particles, the depth of the scratches it leaves and how fast it removes material. There are two grit standards: American (CMI) and European (FEPA). Sandpaper using the European standard often has a "P" in front of the grit number. A higher grit number means finer abrasive particles.
Below 220-grit, they are similar. Above this number, the FEPA grit is more coarse. It is important to know which type of sandpaper you are buying. If you find an American 600-grit sandpaper works well, buying P600-grit sandpaper will not give the same finish.
Start out with a 220- or 150-grit sandpaper and see if works for the initial sanding. If you have to step down to a more coarse 60-grit, you still will need the 220- or 150-grit for the intermediate sanding. For final polishing with a disk sander, grits as fine as P4000 are available.
There are several types of abrasive materials available. Aluminum oxide is the best for your project. It is relatively inexpensive and easy to find in home centers. The aluminum oxide particles are friable. This means the particles break off and create new sharp edges as the sandpaper is used. This extends its life.
Depending upon the intricacy of the detail in your woodwork, you may find sanding sponges easier to use than folded sandpaper when you want to get into curved areas. These sponges are available in many grits and thicknesses. Various sponge densities (stiffnesses) are also available. Sanding sponges are inexpensive, so try several sizes and densities. They have a long life.
Send your questions to Here's How, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com. To find out more about James Dulley and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.