The bulk of the following article applies mainly to to cruisers rather than to the smaller runabouts.
The width of the lift is every bit as important as the capacity of the lift. This is especially true for wooden hulls. If your boat has a 14' beam do not use a lift with less than a 16' width. It may very well crush your hull inward. The straps should not put undue, inward pressure on the sides of the boat, regardless of the boat's size. A lift at least 2' wider than your boat's beam is recommended.
The number of straps to use is another important fact of lifting your boat. The larger the boat the more important it becomes. Fiberglass boats have a better tolerance for being pulled out of the water than do wooden boats. Two 12" wide straps should easily lift a boat under 30'. Over 30', Insist on using four 12" wide straps with heavy spreaders. Wooden boats need four 8" wide straps if they are 20' to 30'. (Webmaster's note: I have lifted a 23' wooden boat with two 2" wide straps without damage of any kind. The straps should, however, be placed directly under ribs.) If they are over 30', use four 12" or wider straps on heavy spreaders.
The reason for multiple straps is simple. The more area you place a load upon, the less stress any one area receives. As an example: If you have a 50 lb. block sitting on one foot, it will cause severe pain. If you have the same block sitting on both of your feet and both feet of a friend, the pain is reduced to a more tolerable level.
One special concern with a wooden boat is the distance it will be carried in the slings. It is better to have the boat hauled when the yard is nearly empty, considering the temperatures are warm enough to do the jobs at hand. Normally the yard will block the boat right next to the lift. The closer you stay to the haul out area the better for a wooden hull.
Heed these words of caution. Do not listen to the person at the marina when they make statements such as:
"I never dropped a boat yet; or,
You only need two straps on that boat; or,
If it breaks apart while I am lifting it, that stuff needed fixing anyhow; or,
It will not push in that hard on the rub rails; or,
I've been doing this my whole life, and you're telling me how to lift your boat."
Use your best judgment when finding a lift and during the process of hauling your boat. There is no more heart wrenching sight than watching a boat being crushed inward or crash to the ground while being hauled.
The lift operator will start the lift slings rising under your boat until he feels slight pressure on the slings. At this point check the boat and slings to make certain the slings are in the right position, the boat is centered in the lift and nothing will bind or catch on the way up. This is the best time to place carpeted 4" x 4" blocks above your splash rails between the hull and the slings. The slings will now place the pressure on the blocks, not the rail and the carpet will protect the hull's finish. All too often, the splash rails on a wooden boat are pulled upward and loosened from the hull if these blocks are not used. Remember to use these blocks again when the boat is lifted for launching.
When the yard lifts your boat, carefully observe the lift points for contact with thru-hull obstructions, such as knotmeters, transducers, splash rails, etc. Adjust the straps to avoid putting pressure on these fittings.
Before the lifting equipment is released and the boat is left to rest on the keel blocks, be sure the boat sits at a slight up-angle with the stern down so the cockpit and deck can drain.
The weight of the hull must be distributed evenly along the length of the keel, not just at one or two points. Use 3 - 10 x 10 keel blocks placed in a straight line under the keel every four feet, two crosswise and one on top lengthwise. Run a string line from the top of the first block to the top of the last block and make sure that all the blocks in between are just touching the string. If the blocks are not at the same height then the boat could develop a permanent hog or sag that changes the shape of the boat.
Boat Stands are use to stabilize the boat while the keel blocking supports the boats weight. Use the jack stands in pairs one placed to port and the other to starboard every 8' of a boat's length. Be sure and use plywood under the stands if the ground is in any way soft. Run a string line along the top plate of the first boat stand to the top plate of the last stand and make sure that all the top plates in between are just touching the string. If the jack stands are not aligned then the boat could develop a twist. If the keel blocks or boat stand bases settle in the dirt or asphalt unevenly, the boat could develop a twist or hog, so adjust the stands up or down every couple of weeks.
Supports must be placed under the transom at the centre line and to the port and starboard sides as well. Independence, a 55-foot cruiser, has a 125 gal. fresh water tank that when filled weighs 1,042 lbs. Each fuel tank contains 200 gal. of diesel fuel for a combined, gross weight of 2,720 lbs. That means, the total weight of fuel and water in the Lazarette is 3,762 lbs., which is a lot of weight in a small concentrated area and it is exerting a great deal of pressure on the keel and transom of the boat. If the transom is not adequately supported then a lasting sag could develop.