I have done it before like this. You need a really hot (90s or higher) sunny day, a sturdy table that is true, several heavy batteries(old gel cells or garden tractor batteries), and some wood shims. The table needs to be in the direct sunlight all day. First, put the hull on your "true" setup board and press down on the sponsons one at a time to find out which sponson bottom is true and which one is raised up in the front or the back. Measure how much out (high/raised) the rasied sponson tip or rear is out (1/4 inch, 3/8s, etc.). Once you know which sponson tip or rear needs to go down, set the hull out early in the day in the sun for about two hours. Then place a large heavy battery on the top of the true sponson, it should hold that sponson down flat on the table. If you have a weak hull you may need to use a sturdy piece of wood or aluminum between the battery and the sponson top to evenly spread the load. The other sponson is going to have one end up off of the table, say it is the front tip. If it is 1/2 inch high at the tip, then put a 1 inch thick shim under the very rear edge of that same sponson. Place another heavy battery or batteries on the raised sponson pushing it down. It may not go all the way down but that is OK, the heat will work it down as the hours pass. Leave it in this configuration all day and then into the night. This is critical as you want it to cool down under the pressure of the weight. You put twice as much shim under it as you were out, that is OK because the hull will try to rebound after it cools but in my experience they only do so about half the amount that you pushed it. I had seven hulls get warped in a fire and was able to save several this way. You may not get it perfect the first time, may have to do it a second time applying a smaller amount of adjustment. Hulls are big money especially if you have a nice paint job already on it, so it is worth all of this trouble to save it. Hope this helps, Beasley
