Does anyone know what the grey putty is named which manufacturers use to seal cables etc going thru van roofs?
Kebbin said
07:33 PM May 18, 2018
It would be some form of Butyl Mastic.
madaboutled said
09:36 PM May 18, 2018
Kebbin wrote:
It would be some form of Butyl Mastic.
In an ideal world it would be Butyl Mastic, but these days the "tradies" take shortcuts and use silly-con. Easy way to tell is to get a thin nail or strong needle and pierce the skin, by pushing it into the blob a few millimeters . If it comes out wet or tacky chances are its Butyl Mastic if it comes out dry its most likely silicone.
swamp said
06:37 PM May 22, 2018
Hi
As we all no
Butyl mastic generally black grey soft putty when new mild tack . Goes hard over time and looses colour . Losses its sealing ability
Silicon sets sold and rubbery /flexiable VERY VERY hard to remove items when this has been used .
Urethane sets hard and permanent
There are now RV silicon sealant . WAY WAY more flexible than std stuff and does not stick like superman --removable
SIKA Sil Industrial
TheMonties said
07:20 PM May 22, 2018
Other outstanding Sika products are Sikaflex 227 and Sikaflex 255 extra.
Both are polyurethane specialist Automotive sealant/adhesives and are available in black, white and grey. They are UV stabilised, meaning they wont break down or lose elasticity in direct sun.
Cheers.
darjak said
11:50 AM May 24, 2018
I use Sikaflex-291 that's what most good caravan and boat manufacturers use.
Can keep it in fridge for 12mths after opening.
In an ideal world it would be Butyl Mastic, but these days the "tradies" take shortcuts and use silly-con. Easy way to tell is to get a thin nail or strong needle and pierce the skin, by pushing it into the blob a few millimeters . If it comes out wet or tacky chances are its Butyl Mastic if it comes out dry its most likely silicone.
As we all no
Butyl mastic generally black grey soft putty when new mild tack . Goes hard over time and looses colour . Losses its sealing ability
Silicon sets sold and rubbery /flexiable VERY VERY hard to remove items when this has been used .
Urethane sets hard and permanent
There are now RV silicon sealant . WAY WAY more flexible than std stuff and does not stick like superman --removable
SIKA Sil Industrial
Other outstanding Sika products are Sikaflex 227 and Sikaflex 255 extra.
Both are polyurethane specialist Automotive sealant/adhesives and are available in black, white and grey. They are UV stabilised, meaning they wont break down or lose elasticity in direct sun.
Cheers.
Can keep it in fridge for 12mths after opening.