I am a Retired Navy Parachute Rigger, more aptley called Aircrew SurivalEquipment man now.That said i have usaed nylon thread on a lot of various projects for indoor use. It is very strong but unfortunatley it does not hols up well in constant exposure to the elements, sun is a real killer. I use dacron thread on all my outdoor projects and it holds up real well. Most all commercial sewing for outdoor use is dacron thread. Check out Sailrite.com that is where I get my thread, they are also a wealth of information on other sailing sewing projects Bill Neuman S/V So Fuch Mun H22