DRAGONFLY Trimarans User Forum

The hatch lock on our 920 was getting progressively stiffer last season and now has seized solid (fortunately in the open position so at least we can get in and out). The hatch garage panel which contains the lock is bedded in sealant of some kind but there are no obvious fixings. There doesn't seem to be any way of getting to this internally either. Has anyone any advice on removing the hatch garage so we can get at the lock, and where we can get a replacement?

(As an aside. we tried all sorts of silicon sprays to ease it but they did little good. Any advice on preventive maintenance assuming we get to fit a new lock?)

Greg Lamb wrote:The hatch lock on our 920 was getting progressively stiffer last season and now has seized solid (fortunately in the open position so at least we can get in and out). The hatch garage panel which contains the lock is bedded in sealant of some kind but there are no obvious fixings. There doesn't seem to be any way of getting to this internally either. Has anyone any advice on removing the hatch garage so we can get at the lock, and where we can get a replacement?

(As an aside. we tried all sorts of silicon sprays to ease it but they did little good. Any advice on preventive maintenance assuming we get to fit a new lock?)

If you have any instruments mounted in the "garage" front you can get rear access with your hand by removing one or more instruments. If not, it's a good time to install some

You also might be able to get access by removing the the sliding acrylic, by removing the stainless strips that hold the sliding hatch. I have not tried this, however.

Last summer I had the same problem. I sawed out the fiberglass around the lock and replaced the fiberglass with a stainless steel plate. The total thickness of the stainless steel plate is the thickness of the fiberglass + 2 mm.
The steel plate overlap the fiberglass (10-15 mm) on all sides, and where the overlap is, the thickness of the stainless steel plate is reduced to 2 mm. The plate is attached with 6 rivets. Before mounting the plate, the new lock is placed in a hole in the steel plate, exactly in the same position as the old one.
OK, well functioning and even a bit exclusively looking
I can send you a picture if wanted
//Henrik

Last summer I had the same problem. I sawed out the fiberglass around the lock and replaced the fiberglass with a stainless steel plate. The total thickness of the stainless steel plate is the thickness of the fiberglass + 2 mm.
The steel plate overlap the fiberglass (10-15 mm) on all sides, and where the overlap is, the thickness of the stainless steel plate is reduced to 2 mm. The plate is attached with 6 rivets. Before mounting the plate, the new lock is placed in a hole in the steel plate, exactly in the same position as the old one.
OK, well functioning and even a bit exclusively looking
I can send you a picture if wanted
//Henrik

We had the same problem on a previous boat, a D920 Hybrid. Despite thoughts that the lock was completely stuffed, washing it out with water removed the salt and following it up with WD40 made it as good as new. May not be the fix for you but worth trying.

Many thanks to those who have replied. I thought I would try the simplest solution first - flushing out the lock. I had an old plant spray bottle which I filled with warm soapy water and squirted most of it into the lock. And it worked! The lock isn't perfect, but at least I don't feel I am going to snap the key when I turn it. If all it takes is doing that once or twice a season then I think we have avoided a difficult and expensive fix.

Lubricate with graphite, available at your local hardware store. Careful, makes stains on pretty fiberglass.