zipper lock

I have found that the older style zippers (aluminium?) completely degrade when they seize shut for too long (months?), so if soaking it is of no use then looks like you need to break it open.

As long as you don't damage the plastic zipper teeth in the process you should be able to get a new zipper-thingamy and you are back in business.

Hot water then laundry soap.

The short answer, nothing. Once it's jammed it's stuffed. You can free it up a little and use it but you cannot fix it short of having the sliders replaced. That's easy to do and costs about $8-$10 a slider at any luggage repair place.

If you want zips that last forever then you need plastic zips with plastic sliders.

All Cabrinha bags have plastic zips and plastic sliders. I have one that is 5 years old and good as new.

Strangely my Balin surfboard bags and my Dakine kiteboard bags have aluminium sliders.

you must be joking!!!

Worst bags and zippers of them all. I have to pack and unpack them all week. Worst I say

Fair enough. You've got the experience. What's so bad about them? I have had no problems.

My main TT has had over 300 sessions for 370+ hours of use. That's at least 300 openings, closings, stuffing in the car, strapped on the roof and driving through rain etc. That bag is literally good as new. Usually when I get a new board I get them to throw in a free bag. The old bag was in such good condition I didn't bother this time.

My strapped surfboard has just under 80 uses. There is a tiny hole where the pointy nose of the board gets rammed down into the bag. Everything else is just fine.

My lightwind TT has a Dakine bag. That's only got about 120 uses on the bag. The bag is fine but I had the sliders replaced recently.