Despite common mythology, silicone sealants are safe for aluminum and do have an important (but narrow) place in vintage trailer restoration. While we recommend using only polyurethanes (like TremPro 635) for most applications, silicone works better in a few applications. Here are a few examples:
It is sometimes difficult to find silicone RTV in aluminum color. To help with vintage trailer restoration, we sell quality TremPro 644 silicone RTV in aluminum color only.
TremPro 644 RTV is a one-part, acetoxy silicone sealant that cures to a flexible rubber when exposed to moisture present in the air. It has a vinegar odor when first applied. TremPro 644 RTV is specially designed for sealant joints between most non-porous materials such as glass, aluminum, metal and metal alloys.
Comes with a convenient screw-on tip.
Click here to see a PDF version of the silicone TremPro 644 RTV Technical Data Sheet
For comparison, here are the Technical and Safety data sheets for polyurethane Trempro 635, which we also sell.