IMM Frequently Asked Boat Lift Questions
Q: What is better, Aluminum Lifts of Galvanized Lifts?
A: When aluminum lifts first emerged on the market, we all knew they were stronger and longer lasting than steel. The primary drawback was cost. The large structural shapes needed were hard to obtain. As structural aluminum became more common, the cost of aluminum lifts closely approached the price of galvanized. Today there is really no reason to purchase a galvanized lift.
Q: Why don't more boat lift manufacturers utilize Stainless Steel Drive Shafts?
A: In the days before cable winders, the the cable would wind directly to the drive shaft. The stainless cable eroded the galvanizing, and the shaft rusted. Cable winders eliminated this issue. The other reason we don't use stainless drive shafts, is, in a twisting situation (which is how the shafts are used), the stainless is far too week. Our structural engenders will not certify a boat lift using a stainless steel drive shaft. They sound good but they are not safe. IMM has always guaranteed it's drive shafts (parts AND labor) for as long as you own the lift.
Q: What type of drive shaft bearings are best:
A: There are basically three types of drive bearings
- Roller Bearings: they seem great, but don't hold up when bolted to an aluminum structure
- Metal to Metal: Some manufacturers use bronze, some use aluminum. In both cases, they demand CONSTANT maintenance. We feel that a boat lift should free up your time, not waste it.
- Nylatron: This is a very high tech, self-lubricating material. IMM has used this material for 17 years, and has never had a bearing wear out. IMM warranties the Nylatron (Parts and Labor) for as long as you own the lift. Occasionally during the break in period, it may be necessary to lightly lubricate the bushings. There is a provision for this.
Q: Should my aluminum lift be bolted or welded together?
A: Unfortunately, most aluminum lifts are built like galvanized lifts. Aluminum is a wonderful material, but the production methods used in its manufacture is different than galvanized. Structural aluminum is heat treated to give it strength, which it needs to hold together and do its job. When the material is welded, the area around the weld is severely weakened. For this reason there should NEVER be welds that are supporting the heavy loads inherent in boat lifts. These points of stress should be mechanically fastened. This is not an option, rather, a simple fact. If you want an unbiased option of this, please feel free to "Google": "Welding Aluminum Alloys". Find the "Lincoln Electric" website. Lincoln is one of the largest manufacturers of welding equipment where many boat lift manufacturers purchase their equipment. Take a look at their FAQ section, and you will see that high treated aluminum (we all use 6061-T6 type aluminum) which is heat treated. This type of aluminum loses 30-40% of its strength when welded. Some of the strength could be regained if the metal was re-heat treated. This is only possible under very controlled conditions. No boat lift company has such capabilities.
Q: Is a chain drive stronger than a belt drive:
A: It would seem so, but the chain is the actual "final drive". This means that the chain is holding the weight of the boat. If the chain breaks, or worse, jumps off, the boat will fall. With a belt driven system, the belt is simply the drive mechanism that turns a gear shaft. If the belt fails, the lift will be inoperable. Your boat, on the other hand, will be absolutely safe, and will NOT fall.
Q: I have very shallow water, how can I prevent my cables from tangling if the cradle goes to the bottom?
A: This is probably the number one issue faced by all boat lift manufacturers AND owners. Every manufacturer has tried to solve this problem with mixed results. Until now, the fixes in place rarely worked, and in many cases provided a slough of additional problems, including causing the loose cables to bunch up and sever one another. Our successful product, the IMM Boatlifts "Slack Attacker" is on the most revolutionary product on the market for shallow water boat lifts. This patented device solves the problem. It's approach is simple yet effective. Visit our page on the IMM Boatlifts Slack Attacker for more information.
Q: Will the cradles on an aluminum lift float?
A: On many lifts that use materials that are too light, or bunks that are made of a buoyant wood, an aluminum cradle will float, causing many, many problems. IMM Boatlifts' revolutionary Perma-Bunk 2000 prevents any cradle-float. We want you to enjoy your boating exerience, from start... to finish.
Q: Do the electric motors need to be covered?
A: In some direct gear drives the motor is not covered. As long as this is a Stainless Steel Washdown Duty motor this is OK. Be very careful to check that it is, in fact, a WASHDOWN DUTY. Do not assume because it is Stainess Steel that it is washdown. If it isn't it MUST be covered. Being sealed is not enough. This can be a serious safety issue.
Q: Are enclosed top beams better than open driveshafts?
A: With an enclosed top beam the cables are not visible. If there is a cable problem, such as a tangle, there could be a significant amount of damage before the problem is noticed. Another issues is that saltwater is drawn into the beam every time the boat lift is raised. Water evaporates, leaving behind a high concentration of highly-corosive salt. With an open shaft, either rinsing, or rain will eliminate this problem. Another concerning issue is birds and rodents. Dark warm places are their favorite and closed beams are the perfect location. The site could be quite grisly after a long period of non-use when Mr. Squirrel meets his maker thanks to your closed drive shaft.