The orbital sander is the best. A belt sander is too aggressive. Before you do anything see if the paint will chip easily. Depending on how old the are the might have been stained before and finished. You could use a cabinet scraper to get some of the paint off. Then use the sander.
Well the simple fact is that hand sanding has many benefits over power sanding that can often be overlooked. Firstly, a final hand sand before finishing will always give a better finish than ending with a power sander as, no matter how fine a grit you use, there will always be scratch marks left by the power tool.
Random orbit sanders offer a good balance between effective material removal and refined finishing. Their dual-action motion allows them to sand more quickly than orbital sanders while producing a smooth finish.
Don't do it. The weight of the sander, plus your hand and arm, is enough pressure. Pushing down does remove wood faster, but it's counterproductive. It can slow or stop the pad's rotation, creating those ugly swirls.
The Golden Rule of Sanding
The golden rule for choosing your sequence is to never skip more than 1 grit. For example, if you start with P80, and need to finish at P240, rather than using every grit from P80 – P220, you can do P80 – P120 – P180 – P240. This sequence cuts out P100, P150 and P220.
The first commandment of sanding: Sand with the grain. But when you have a lot of wood to grind off, break that rule and run your belt sander diagonally across the grain (at about 45 degrees). Instead of scratching away at the wood fibers, the belt will rip them out. It's incredibly fast—and dangerous.
The biggest difference is that a random orbit sander gives a smoother finish and is more versatile, while a palm sander is better for quick, rough sanding.
If you're dealing with cabinets in relatively good shape, you may start with a finer grit, such as 120 or 150. However, for cabinets with noticeable imperfections or rough surfaces, you'll want to begin with a coarser grit, like 80 or 100, to level them out.
Sanding is an important part of many painting projects. The right sandpaper, sometimes called “grit paper” along with an accompanying tool like a sanding sponge or a sanding block, will help you properly prep surfaces like wood, metal, drywall, and laminate prior to and during painting, ensuring an ultra-smooth finish.
Unlike regular sandpaper, it just removes gloss; it can't be used to smooth the surface, correct imperfections or as a paint primer. Liquid sandpaper is also referred to as deglosser and wet sanding. The advantage of using liquid sandpaper instead of regular sandpaper is that it's easier to apply and safer to use.
Random-orbital sanders are some of the most versatile power sanders.
Apply a bonding primer that's designed for cabinets using a 2 1/2-inch angled brush or small roller. Work in the direction of the wood grain and smooth out any drips before they dry. Allow the primer to dry per the manufacturer's instructions. This usually takes about two hours.
Gang sanding with a random orbit or belt sander allows you to smooth edges in one pass.
Sanding with the grain is the golden rule of woodworking, which means moving the sandpaper in the same direction as the wood grain. It helps to minimize visible scratches and results in a smoother, more professional-looking finish. It's not always clearly visible which way the grain runs on some types of wood.
After sanding a piece of wood, you'll need to clean it before adding a stain or paint. You can use a variety of tools and techniques to remove sanding dust from your wooden surface. Just make sure you get the surface of your project as clean as possible before adding any paint or stains to finish the piece.
One common mistake is not replacing the sandpaper frequently enough, especially when it becomes clogged. This often happens due to a lack of experience or the desire to save money by using fewer sandpaper sheets. However, continuing to sand with worn or clogged sandpaper is a big mistake.
Don't push down, even the slightest bit. The weight of the tool and your hand is enough to get the results you want. In fact, pressing down can bog the motor, slowing down the process and harming the surface. Let the sandpaper do the work.
Using the wrong grit sandpaper, exerting too much pressure, failing to keep the sander moving, ignoring dust collection, and skipping edges and corners are all mistakes that can result in uneven surfaces, damage, and poor results.
Sanding discs not sticking can be caused by surface contamination, worn-out backing pads, or using the wrong type of disc for your sander. Environmental factors like temperature and humidity, improper application techniques, and degraded adhesives can also affect adhesion.
While the dial can be set from 1 (low) to 6 (high) speed, the recommendation is from 4 to 6 on all surfaces and with all sanding grits besides light sanding on paintwork (2 to 3 is recommended, in grits ranging from 180 to 400). Setting 1 isn't recommended for any sanding situation.