Why Mechanics Put Sandpaper Inside Engines!

Is it safe to use sandpaper to hone an engine cylinder?! ⚙️🔧
When you rebuild a combustion engine and install new piston rings, you cannot just put them into a perfectly smooth, polished cylinder. If the metal walls are completely smooth, the engine oil will simply slide off, causing the bare metal rings to scrape against the bare metal block!
To fix this, mechanics use a "cylinder hone." This tool spins abrasive stones inside the block to scratch a microscopic, diamond-shaped pattern into the metal called a "cross-hatch." These tiny scratches hold the oil, creating a fluid barrier that helps the new piston rings break in and seal properly! While professional tools use specialized stones, many DIY mechanics try to save money by wrapping standard sandpaper around the tool! While it works in a pinch, cheap sandpaper sheds dangerous grit that can destroy the engine if it isn't washed out perfectly!