A question was raised about whether using a stainless steel prop was better than using an aluminum prop for trolling. The question was on a fishing report thread. So I brought the question here. Here are my thoughts on the matter. The first point of business is to determine what type of motor you’ll be using to troll with. Most sport fishermen are using one of the following motor types; a small horsepower outboard motor commonly called a kicker motor or their main motor that maybe an outboard or an inboard/outboard. There are two numbers mostly commonly used to describe a prop. The outside diameter and the blade pitch. The outside diameter is the measurement of the circle the prop makes when spinning. The blade pitch is how many inches the prop moves through the water for one revolution minus slippage. Small OBs make great trolling motors and do not troll any better having a stainless steel prop verses an aluminum prop. If you’re looking at upgrading a small OB for trolling and it doesn’t have a four blade prop then get a four blade prop made from aluminum. The four blade prop should make steering better while trolling. The OB will most likely lose some wide open throttle, WOT, RPMs but nothing to worry about. For a main engine outboard motor or an inboard/outboard that is being used for trolling there is no difference between a stainless steel prop and an aluminum prop. A stainless steel prop will not deform under load like an aluminum prop will. That’s why on most marine engines larger than 120 HP you see a stainless steel prop. An aluminum prop will absorb more damage if you hit something before transferring the impact to the prop shaft and gear case. Stainless steel props are built with thicker blades and the additional mass creates more momentum so if you hit something you may not damage the prop as much as you damage some other drive train component. When comparing a stainless steel and aluminum prop with identical diameters and blade pitches you’ll generally see that the stainless steel prop will provide a better hole shot and top end speed. Most aluminum props are painted white or black. Stainless steel props can be black, buffed or highly polished. I have seen a few fisherman paint their props “Rocket Red” to attract salmon but that’s another thread.