abrogard

Sorry to go missing for so long - screwup with my computer. Thanks for all the replies. I've been thinking I could just open the aluminium panels under the seats and fill the area with polystyrene foam. I don't know the SG of it but it sure floats high in the water, doesn't it. Wouldn't be far from weightless. The volume of a litre of water replaced by polystyrene would be near enough to 1kg weight saved, I'd say. Or if we give polystyrene an SG of 0.1 then maybe it'd be 900gm saved? So the big seat is about 1.2m x .3 x .2 = 0.072 google tells me. That'd be .072cu mt = 72 litres = 72kg I think. Well with the other seat and the tiny bows seat I reckon I could about double that so I'd be looking at a bouyancy of something like 140kg. So the question becomes: how much would the boat weigh? If it is less than about 140kg I should have a chance of making it floatable by my rough reckoning and if it is up around 200kg I'd say I've got no show. I'll take it over the weighbridge when I get the trailer fixed up and registered - meantime maybe someone's got a ballpark figure for the typical tinnie?

My aluminium dinghy - small ten foot job - possibly (I've just learned) an old De Havilland - has three enclosed seats in it. Like there's aluminium panel front and aft of them, you can't see under them. If I filled them with styrofoam would it be enough to make it unsinkable? Or what would?

Okay, thanks guys. Nobody happens to know about the feasibility of welding up little holes, though? In case for some reason i wanted to go that way. Like would it be a tiny job for an aluminium welder, dab, dab, dab, or would it be time consuming, skill demanding? Like I find welding thin sheet steel with a MIG time consuming, skill demanding. Or perhaps even detrimental to the integrity of the aluminium sheet all around.

Yep. I like that idea. I'll check it out. Thanks for those pics. Looks good. Talking about a bit of welding repair - my little boat has apparently been made by using some kind of rivet or screw maybe, going right through the hull, to fasten the seating down. I don't like it. Can't really see what they are because they're all covered in some coating. But I fancy to have them all cut off and the holes welded up. Is this a feasible, sensible thing to do with aluminium? Weld up all these little holes?

Yep, I'll do that guys - buy a whole new thing and put it in. Talking about overhauling - how do you 'clean' up an overpainted aluminium boat? Our local paint shop prop. has been telling me don't use paint stripper because it'll eat away at the metal, especially around screws and such, and sanding and scraping can take too much metal off and... I don't know what.. What's the go?

Thanks for the replies, guys. I guess it'll be install a whole new thing. I'll scrape the paint away and have a good look at it. I'll post a pic. It might amuse some folks - a tinny painted with layers of housepaint the way you see big ships painted. Oh... I tried to link to a couple of pics of the plughole but I got a message that I wasn't allowed to use that 'image extension' on this board. I guess that means Picasaweb? I'll try photobucket. Here's a photobucket link rather than an insert to here http://s307.photobucket.com/albums/nn281/abrogard/boatpics/

We just got an old aluminium tinny. About 3metre dinghy. It has no drain plug. The guy I got it from says he hasn't got it. I can't find anything to fit. I tried different bolts with fine threads, nothing fitted. I got directed to plumbers fittings and tried their things and nothing fit. I looked in boating catalogues I found on the web and bought a plug, waited a week for it to arrive and - it didn't fit. What I have is a hole of about 17.5mm internal diameter with some kind of fine thread in there. Does anyone have any clue what this might be? regards, ab