Aluminium Window Frames

WherryNice · November 21, 2021

Time to ask the experts.......

I recently removed one of the leaking windows from my Safari and stripped it down ready to refurbish/reseal etc.

The black mastic that seals glass to frame had dried out and perished; this I expected and have sourced suitable sealant to rebuild with however, where the frame joins together and over any screw fixings, there was a sticky/gummy type of clear(ish) sealant or adhesive that was a real pain to remove and I can't for the life of me work out what it is and whether it was there originally or something a boatyard may have added to 'cure' leaks? There was a lot of it and it was also seemingly used to stick the rubber pieces that sit in the channels over joints etc too.

Any suggestions as to what it might be would be greatfully recieved. Thanks in advance:)

floydraser · November 21, 2021

I have no idea what it may be but if it's dry to the touch it could be silicone. If it's oily under the top skin and sticks to everything I still have no idea what it is but I had some brown stuff like that on mine. Someone somewhere suggested using WD40 to remove it and it worked for me.

Oddfellow · November 22, 2021

Bed your windows back in with ArboMast. Use nothing else.

as for the material you can't identify, speak to Trevor Preece

Vaughan · November 22, 2021

13 hours ago, WherryNice said:

and have sourced suitable sealant to rebuild with however,

Keeping leaks out of window frames is a bit of a dark art!

I just wanted to make sure you understand that Sikaflex, or any other mastic product that mentions the word "glue" in its description, is not suitable. It may fix your leak but you will never get the window off again afterwards.

Window seals in a Fibreglass boat move a lot, especially if you hit the bank hard, so they cannot be of a product which drys out solid.

BroadAmbition · November 22, 2021

especially if you hit the bank hard,

Who would do such a thing?

No one in here surely!

Griff

Bikertov · November 22, 2021

2 hours ago, BroadAmbition said:

especially if you hit the bank hard,

Who would do such a thing?

No one in here surely!

Griff

Is that the river type of bank or the financial institution type of bank ...

annv · November 22, 2021

Hi It is most probably Leak Sealer/crack sealer. it comes in liquid form that you run along the gap and creeps in, then dries to a tacky substance easily removed with petrol or meths. John

Smoggy · November 22, 2021

If using any type of gooey sealant check the frames still fit the hole before before applying the gunge.

WherryNice · November 22, 2021

Thanks for the replies folks, as it doesn't appear to be a commonly known product I think I will just use some of the Arbo butyl sealant on the places where this other stuff was and see how it goes. Cheers

Vaughan · November 23, 2021

By the way, for general information :

To stop a leak in emergency, run a fillet of normal oil based yacht varnish around the outside edge, and it will enter the joint by capillary action and repel the water as it dries.

Something like International Blue Peter, but not 2 pack or polyurethane, slightly thinned with white spirit. You can even put it on in the rain and it will stop the leak for quite a long time, maybe a couple of years.