Q. Is COMPROP a primary prop or a spare?
A.COMPROPs are full-time, primary propellers. Many boat companies such as Regal, Wellcraft and Four Winns have used our COMPROPs as standard equipment. Basically, if the boater is satisfied with aluminum performance, he/she will be happy with COMPROP. If the boater is more demanding and wants the extra performance of a stainless steel propeller (and doesn't mind the lower unit risk & price), a COMPROP would be a good choice for a backup.

Q.What are the best applications for a COMPROP?
A.All types of family & fishing boats from 20 to 225 prop shaft horsepower. If a boater is using an aluminum prop and is happy with the performance, he/she will be happy with a COMPROP. If stainless steel performance is preferred, the COMPROP could be an on-board backup. (Aluminum props and COMPROPs generally do not perform as well as stainless steel propellers.)

Q.How does it perform?
A.Very well. Similar to an aluminum prop. Our new four blade series COMPROPs have shown in tests by boat builders and major boating magazines to be at least as fast as top-notch aluminum propellers. In most tests, they were faster. Boaters will find the new four blade COMPROPs also accelerate quicker, corner much better, and are very smooth at all speeds.

Q. What is it made of?
A.A high-tech composite material similar in strength to some aluminum alloys. We consider the actual composition of COMPROP to be a trade secret.

Q.How tough is it?
A.Tougher than aluminum in most cases, not as strong in others. COMPROPs are extremely tough in low speed/soft bottom condition. If a boater is routinely digging up sand, mud, gravel, etc., while at low speeds or trolling in shallow waters, the leading edge geometry will become scratched, but will not fold or blunt like aluminum props. If continually dragged through the mud or sand day after day, the COMPROP will gradually wear away the outer diameter. This will not affect performance significantly unless taken to extreme. Aluminum propellers cannot withstand this type of environment. It is much too severe. They must be repaired regularly.
     On the other hand, while traveling at a high speed, if a boater strikes a stump or other underwater object and has a severe prop strike, the COMPROP blades are designed to break awayto reduce stress to the lower unit. In this instance, a COMPROP costs less than expensive repairs to the drive train. Remember, always carry an extra COMPROP and tools to change a prop.

Q. Are 4 blades better than 3?
A.Yes - for most applications. Increasing the number of blades improves static thrust (acceleration) abilities. It also improves cornering and fuel efficiency while reducing vibration. If top speed is the highest priority, the fewest number of blades is desirable. (Fewer blades mean less parasitic drag at top speed. Miss Budweiser, the unlimited hydroplane, uses a two bladed propeller, but she gets a running start.) COMPROP four blade designs run just as fast as three bladed aluminum propellers.
     Keep in mind adding blades increases manufacturing costs in metal props. Most aluminum props have three blades because it offers a good compromise between performance and cost. We have an advantage at COMPROP. Due to our manufacturing method, many secondary operations are eliminated. We are able to offer composite 4 blade props at prices considerably less than 3 blade aluminum props.

Q.I have a 3 blade 19" pitch prop. Which 4 blade is correct?
A.Ours is a simple 3 to 4 blade conversion. COMPROPs are labeled with pitches similarto 3 blade aluminum props. If you boat uses a 19" aluminum 3 blade prop, use a 19" COMPROP. If we do not offer a 19" for your application, our 18" and 20" pitch 4 blade models will be very close in performance.

Q. Are COMPROPs more expensive?
A.When in a soft bottom/shallow water environment, the leading edge of an aluminum prop will scar badly and be in need of a repair frequently; the COMPROP will not be damaged (as described previously). After a severe prop strike, an aluminum prop may or may not be repairable. Sometimes the damage is too great and a new prop must be purchased.
     Aluminum propeller repair costs vary significantly. Generally there is a choice between one new aluminum propeller plus two repairs, or three brand new COMPROPs. Keep in mind after several repairs to an aluminum prop, it becomes brittle and hard to repair. Each repair may also detract from original performance.
     In summary, aluminum propellers may be more costly to use due to the constant need of repair in certain environments. If severe prop strike situations are common (i.e., new boat drivers or unpredictable water depths), costs may be close, but COMPROP has two clear advantages: 1. Better drive train protection; and 2. A new COMPROP will easily outperform a repaired aluminum propeller.

Q.Why do some metal propellers have a rubber hub?
A.The rubber hub in some older metal propellers is intended to protect the drive train from propeller vibration, and shift shock. Unfortunately, rubber hubs deteriorate over time and often do not perform as intended. The newest aluminum props use a replaceable, solid nylon hub. Our designs and material eliminate the need for rubber hubs on COMPROPs altogether.

Q.Do the COMPROP blades flex?
A.All propeller blades flex during use. Stainless steel flexes the least; that's why stainless props generally have the best top speed. COMPROPs flex about the same amount as an aluminum propeller; that is why performance is similar.

Q. Are there limitations?
A.We recommend a limit of 225 prop shaft horsepower. We also suggest limiting hull size to 21 feet and/or 3,000 lbs. (If the application is a twin, larger limits apply.) Our COMPROP designs are optimized with these limitations in mind. If you choose to exceed these limits, performance may be compromised.

ACCEPTANCE
It is a challenge to lead the change from traditional metal props to composite propellers. This is similar to fiberglass replacing wood in new boats during the 1950s. Fiberglass was a new material that lowered cost, maintained or improved performance and provided benefits the traditional material couldn't match. There was initial reluctance, then acceptance. It's true, history repeats itself.