Loading or standard load, is a term that is used in the sandpaper industry meaning that the product gets clogged by residue, either sawdust, or more than likely finishing products.
Another term, called “non-loading” or “no-load” sandpaper is available with a special coating applied over the abrasive to help shed the residue.
Another method of creating no-load papers is by the use of a stearate lubricant in powder form to perform the same residue shedding properties. These sandpaper are trademarked as either Carborundum Dry-lube or 3M Fre-Cut.
Both of these suppliers offer these papers in both sheet and disc forms, as well as adhesive rolls, that can be used in power sanders. As you have probably noted, these types of no-load sandpapers are becoming increasingly popular and are now available in most all hardware stores and big box stores.
Even though you will find that these types of papers to be more expensive, the convenience and longevity of the product is more than worth the additional expense.
The grits that the no-load papers are available in generally run from 60 through 1200. (Many of the available grits are available in both forms, ranging as fine as 400, and are available in both the pressure sensitive adhesive and “hook and loop” forms, so you can choose when you employ hand sanding or power sanding techniques.)
The Velcro form can easily be pressed into place on a power orbital sander, and removal is just as easy, with no sandpaper residue being left behind to deal with.
I prefer to use the pressure sensitive adhesive variety with sanding blocks, which eliminates the need to use a spray adhesive.
If you haven’t had the pleasure of using a random orbital electric sander for use in your shop, you most certainly will want to try one with these sandpaper products. You will find that this will make your sanding chores much more streamlined and less boring.
Sterate Coated No-Load Sandpapers:
Sandpapers with the stearate lubricant are often recognized by their bluish-white, beige, or light grey coloration. When you use the sandpapers coated with the powdered stearate abrasive, the abrasives sheds during sanding, more than likely taking the clogging residue along with it. The abrasive becomes dull as the paper wears out.
Non-stearated Coated No-Load Sandpapers:
Even better and more efficient than the stearate papers are the non-stearated varieties that are coated with the no-load substance. Although more expensive, they are more efficient and the results will be noticable. They reason for their efficiency is that they cut faster while not breaking down quite as quickly, although being more expensive.
Be aware that stearates can cause fisheye problems in water-based finishes, such as waterborne lacquers and the stearates were formulated primarily for solvent-based finishes. If you plan on finishing with water-base lacquer, use the coated papers, such as 3M’s gold-colored P-scale to minimize the formation of fisheyes. If using water-based finishes, you should choose the coated, non-stearated sandpapers.