mast base casting

The other day I had the H18 out in light winds, say 5 km/h or so. When I was running downwind sometimes the waves, small as they were, were enough to unload the sail of wind and things would just "flop around". I notices that the mast base casting that is rivited to the front cross bar would move slightly with each load and unload. If I can describe it in workd I would say that the rear most part of the casting would go from touching the cross bar to being off the cross bar by about 1/4 to 1/2 mm.

My question is/are: is this normal, or at least an acceptable situation? What is this suppose to looke like and if not like this then what are my options?

The loosening mast base is just a fact of life for Hobie 18 owners. If it is only moving 1/4 to 1/2 of a mm, that's nothing. I don't even know how you'd really see/measure that. It will eventually get looser over time and the only real solution is to re-rivet the base. I actually sailed on a rental 18 with the mast base completly separted from the front cross bar (and hulls 1/2 full of water...).

Re-revit it when it gets too sloppy. Also a good time to inspect for cracks as the cross bar will eventually fail at the mast step (my boat is on it's 3rd front x-bar).

sm

I recently purchased a 1982 with a cracked front crossbar. I was lucky enough to find a used replacement from a friendly Hobie sailor. I couldn't afford the newer 4 rivet mast base. I cut a 10" upper section out of my cracked one and centered it under the mast base and riveted it in place. In addition to the 2 rivets in the base, I added 2 rivets on each side being careful to stagger them. I thought this was a soloution until I can afford some of the other things I need. Your thoughts on my 'fix' would be appreciated.