Here's a pic of one of them in use that I built for my brother's kitchen cabinets years ago.
The left side is labeled, "Maple". That is the side of the drawer with a tapered groove cut into it.
The male piece, as you can see, is of plywood, and also tapered.
The piece of Oak on the right, is the front face of the cabinet.
What I did was NOT apply any finish on the slide mechanism. I did, however, give it a light sanding to make sure things were smooth.
Second, I coated all of this with Minwax Paste Finishing Wax.
Here is what happens. The wax works it way into the wood. After I built these, and waxed them initially, he only had to wax them one additional time, and they have been using them for over 30 years.
They slide in and out with ease, and noise free.
One of his grandkids shows up, pulls the drawers out part way, and climbs up onto the counter. Grandkid weighs about 50 lbs or so.
