What is the toughest diving glue for aluminum and glass?

I have seen a lot of underwater glue types that claim to resist a 100 feet diving pressure.

Did someone have a good experience with glue that would permanently seal an aluminum flashlight joint… it's a led flashlight, once it is seal; I don't need to un-seal it in the future.

Flashlight head:

aluminum-aluminum joint

aluminum-glass joint

I think you should use RTV Glue.

What about 3M 5200 Marine Adhesive?

Use epoxy

I have seen a lot of underwater glue types that claim to resist a 100 feet diving pressure.

 

Did someone have a good experience with glue that would permanently seal an aluminum flashlight joint… it's a led flashlight, once it is seal; I don't need to un-seal it in the future.

 

Flashlight head:

 

aluminum-aluminum joint

aluminum-glass joint

The pressure isn't an issue for most glues, assuming it's a small crack. Given the proper geometry, you could seal a hole with almost any glue.

Epoxy is strong but can be brittle, so if the aluminum bends with the underwater pressure, the epoxy-aluminum joint might fail. I'd recommend some sort of marine silicone. The silicone is also useful because aluminum expends a little bit more than glass with changing temperatures, so the size of the gap between the aluminum and the glass will change when the flashlight goes into, say, a rinse tank that's been sitting in the tropical sun all day.

I have seen a lot of underwater glue types that claim to resist a 100 feet diving pressure.

 

Did someone have a good experience with glue that would permanently seal an aluminum flashlight joint… it's a led flashlight, once it is seal; I don't need to un-seal it in the future.

 

Flashlight head:

 

aluminum-aluminum joint

aluminum-glass joint

I suggest "Aquamend: Underwater Repair Epoxy Putty" made by Polymeric Systems, Inc. The putty is availabe at Home Depot and even bonds while underwater. I have used this putty for several DIY housings and have never had a problem with leakage, becoming brittle, or cracking. The putty is made for repairing boat hulls and even sticks to Delrin, which most adhesives will just flake off of. The putty is in a two part stick that is easy to use.

I take Aquamend on every dive trip.

Good luck,

Barry

Another very good option is this glue... its liquid

aluminum that most likely is stronger than the

native aluminum that your applying it to...

FasMetal 10, HVAC 19770, Epoxy Putty

Its made by Devcon, tele.. 508-777-1100

from the front of the box...

High strength, aluminum filled epoxy for bonding, patching,

filling and sealing.

Used for repairing large and small holes in aluminum and other

metal castings: builiding up metal surfaces,repairing air conditioning

coils in HVAC cooling units, sealing leaks in pipes and tanks, sealing,

filling, bonding similar and dis-similar metals, wood, porcelain and

other materials....

I can tell you its very very strong... we tested it in a glass bead blaster

to see how strong it was... the bead blaster did not put a dent in it...