1. A cover that is too tight will pull against the tracks and will not operate properly. A cover that is made too small reduces the life of the cover and mechanism, causing premature failure of both the fabric and the mechanism due to the added stress.
2. Fabric shrinks over a period of time. The amount of the shrinkage varies widely according to the weather conditions, particularly the amount of time the cover is exposed to the sun. Slack is always added to the fabric to compensate for potential fabric shrinkage.
3. In order to meet the ASTM safety standards, the cover must lie on the water as most of the supporting strength of the cover comes from the support of the water directly under it.
Each automatic cover that Coverstar manufactures is made with the slack calculated based on the type of track that was used, how far the track is located above the level of the water and the overall size of the cover. Any other variables that may be brought to our attention are also included. Initially, a properly sized cover will drop almost directly down from the track or deck to the water, with some folds & wrinkles as it crosses the pool. Our slack formula is designed to give the cover and mechanism maximum life, as well as making the cover look as attractive as possible.
In some cases, a portion of the slack may be taken up by lowering the water level. However, you should consult with your pool builder or pool service company before doing so. They can advise you exactly where the water level should be to keep the pool equipment operating properly. For more information on Coverstar Automatic Safety Covers, please go to www.coverstar.com.