Loosening stiff sliding windows / tracks

[superheat6k]

Any tips or specific products I can try.

I have one very stiff window that will slide with some effort, and another that simply refuses to budge. The panes are glass, not lexan, acrylic or perspex

The drainage plates lining the bottom of the windows were completely full of moss when I bought the boat, and this has been cleaned out.

I tried recently to remove another of the frames, but the have been thoroughly bonded in with mastic to the extent that the GRP would likely be damaged before the window frames would separate.

I have tried WD40, but doesn't do much. I was thinking of trying sail slider PTFE lubricant.

 

[johnalison]

PTFE is brilliant for some jobs such as tired old Vacuvins, and may work for you, though taking it apart and getting rid of the old crud might be better.

 

[oldharry]

PTFE is brilliant for some jobs such as tired old Vacuvins, and may work for you, though taking it apart and getting rid of the old crud might be better.

+1 form the PTFE spray - brilliant stuff! But it still wont work if there is hard crud narrowing the tracks. If the glass is 2.5mm thick, but the track is only 2mm with crud, then PTFE isnt going to expand it!