if not mistaken acrylic and using weld-on, not silicone, weld-on like water, make your square cut, do not be afraid to put to much down with a fine brush, do not brush, dab it on then set your patch on, put a weight on, say that beer you fixing to drink, it dries flat, so better to much than not enough, sets in 30 seconds. 24 hours for complete bond. I can not over state do not worry about to much. you want no bubbles between plates. i use this stuff all the time at work.