Sealants 3

[PJS1953]

Hi,
I have a problem trying to seal a 3mm gap between steelwork with a material that will keep out water - specifically rain water. The material will be at ambient but it may have to be applied in very damp/wet conditions and set to form a flexible membrane.
I am not a specialist in adhesives but I am looking into silicon sealants and caulking compounds and would be grateful if anyone has any suggestions about a suitable material and types of hand/auto applicators and any specialist tubing that can be added to reach those difficult areas!
Thanks
PJ

 

[MintJulep]

Surface preparation is the key to success with any sealant. Get the surfaces clean. I mean really clean. Otherwise nothing will stick.

If you are forced to apply in wet conditions, look at urethane based sealants that REQUIRE the presence of moisture to cure.

 

[unclesyd]

I would give these people a call with your problem. They have tapes and mastic that may work.

If there wasn't a requirement for flexibility you could use an underwater epoxy.

http://www.densona.com/index.htm

 

[MikeHalloran]

3M brand #5200 marine sealant is urethane based, available in caulking gun tubes from your usual supplier, and in small squeeze tubes from Wal-Mart.

It's very strong, will grip and cure on a wet surface, and will stay flexible in extreme conditions.






Mike Halloran
Pembroke Pines, FL, USA

 

[PJS1953]

Thanks gents these have been helpful tips and we are now carrying out trials on several sealants
PJ