Butyl

[scrottie]

Goo Gone works as well as you could expect on butyl rubber. Acetone doesn't do much. You can't use a portlight retainer ring to clamp butyl down. It isn't strong enough and it'll just strip screws and bend, so you have to put a clamp through the porthole with bits of wood to smash it down, or if the portlight doesn't open, find a way to apply pressure on the outside. Use a big ball of excess butyl to thoroughly rub down the surfaces first until they're both clean and tacky. Loose bits of wood, paint, dust, whatever get pulled up and the butyl goo gets spread around. Heat helps. It makes the butyl relatively soft so it can be smooshed flat and voids pushed out, and also makes it stickier. Don't try to pull excess butyl that was either squeezed out or was just laid down past the rim of the portlight. It will pull butyl out from under the edge and create voids. Instead, cut it with a sharp knife first, then peel off the detached butyl. Repeat every 10 years or longer in cold, sunless climates.

Comments

[rebeccmeister]

What are the indicators that it's time to replace your butyl?

[scrottie]

Well, water inundation is an indication that you were late in replacing it.

[rebeccmeister]

*laughs, then cries*