Model Boat Mayhem
Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: Bill D203 on March 13, 2010, 12:16:28 am
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HELP Help
I have picked up an old boat on flebay this week. Pics to follow soon. This is a departure from my normal OMRA petrol head type boat. When I got it home I found the paintwork was a bit naff. Taking a look inside it looked like a real wood planking, I sanded the paint off and bingo Oak planking. So I want to varnish the Hull to a gloss finish. Now i have got 90% of the paint and crap off it however some small cracks in the joints have opened up. Bare in mind I want to varnish the outer hull dose any one have a good way to tell me how to seal the hull up again ??
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Bill....if access to the inner hull is adequate, you could consider a layer of woven glass cloth or tissue & followed by a coating of fiber glass resin.....this would not only strengthen the hull....but also water proof it too
If the cracking as viewed on the hull externals is concerning, seal these cracks with PVC insulation tape prior to the internal application of the fiber glass resin....easily removed after the resin has cured & eliminates all that extra sanding >>:-(
Nothing like an old traditional wooden planked hull O0...keep us posted with a few .jpgs......... :-))
There are some really good polyurethane aerosol spray packs available.....both in gloss & matt....the only tip is many light coats with a very light sand with 1000 W&D paper between each coat ......Derek
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Have a look at this may help
Peter
http://www.rcgroups.com/forums/showthread.php?t=329811
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Bill....if access to the inner hull is adequate, you could consider a layer of woven glass cloth or tissue & followed by a coating of fiber glass resin.....this would not only strengthen the hull....but also water proof it too
If the cracking as viewed on the hull externals is concerning, seal these cracks with PVC insulation tape prior to the internal application of the fiber glass resin....easily removed after the resin has cured & eliminates all that extra sanding >>:-(
Nothing like an old traditional wooden planked hull O0...keep us posted with a few .jpgs......... :-))
There are some really good polyurethane aerosol spray packs available.....both in gloss & matt....the only tip is many light coats with a very light sand with 1000 W&D paper between each coat ......Derek
Thanks for that. I was thinking of useing glass and resin on the inside.
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Now here indoors has let me of the shopping now have taken some pics to show you all.
If anyone know what the boat is can they let me know as i don't have a clue about the boat only that i like the look of it. And I'm hoping to have it done for Wicksteed park meet this year.
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if it was me I would go with the very fine cloth and skinning resin from Deluxe Materials (very thin) , put it on as if you where doing an aircraft wing, and not put any resin on the inside at all, the reason for that is if you do get any water penetration it will get trapped and will not dry out so will rot , it will also put on weight,
the very fine cloth will put very little weight on and give you minimum of sanding do two layers within 12 hours.
Peter
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hi there Bill
I have seen this boat before, as in Plan, and I am sure its not from MyHobbiesStore. However, I think it may have come from Hobbies Weekly Plan - enlarged. Very old magazine - and if it were me I would use Zpoxy Resin on the outside and give it at least 3-4 coats. Allow the first coat to soak well into the timbers. When the first coat has dried, rub it right back to the timber once again, thus leaving Zpoxy in the gaps and in the grain of the timbers. Follow on then by another 2-3 finishing coats - I suppose you could add either a very fine aircraft cloth between the layers of Zpoxy or even tissue matt. Me, I would use tissue matt. This is because tissue matt soaks up the resin & the fibres begin to loosen and break - you can work these into the tight radius' around the keel where the keel meets the planking without the aid of incorporating air bubbles in there. Remember, the trick with working with any material with resin is to apply the resin first of all and then the cloth/matt over the top and stappel the resin through the material or the matt. This prevents air bubbles from being trapped. As far as epoxying/resining inside the hull goes, yes, definitely do this! It has been proven many times that timber swells in dampness, it doesnt even have to have water on/around it to swell and if you have only sealed one side of it - when it becomes damp or the moisture is in the air, it begins to swell and you have restricted only one side of the timber and it is going to begin to swell - and burst away from your bonding on the outisde. Timber has twice the expansion rate of plastics when in a damp environment. So do seal the inside.
aye
john
bluebird
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This is how the EXPERTS do it,the same can be used on models . also Goggle osmosis have a read about it
http://www.glen-l.com/methods/how-to-fg.html
http://newboatbuilders.com/docs/fiberglassoverwood.pdf
unless you can Guarantee the wood is 100% sealed and water can not weep in don't. there are for's and against doing any fiberglassing never mind both sides
Peter
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Hi there
I have tried googling Osmosis, but just as I knew Osmosis is a process/BIOLOGICAL TERM for water penetration and deterioration of the laminations of fibreglass and gelcoat.
That though is only when it has been in water for a prolonged length of time - a little longer than our model boats stay in the water eh.
The last time I checked the stats for the absorption of water into polyester resin - it was between 6-7 months of continuous submersion and that was only to penetrate about .125 thou.
So who keeps a model boat in water for 6-7 months continuously? Timber absorbs water in a matter of hours and it expands so the only thing the lad has to worry about is to ensure that the exposed timbers are well covered with whatever resin/material he picks to use.
aye
john
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try
http://www.google.co.uk/search?q=osmosis+in+boats&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&redir_esc=&ei=GjWdS_v-FJSi0gSrq_DVAQ
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John is quite right, 'osmosis' simply isn't an issue for model boats. It only manifests itself in full size boats after several years continuous immersion.
Colin
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http://www.westsystem.com/ss/boat-repair/
:-)) try this
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Thanks chaps
I now have it fully striped back and there is gaps in the planking all over the hull. I think the FG and tissue is going to be the only way forwards. Yes doing it that way seems to have some down fulls but I think it is the only way if I'm to get it on the water.
Cheers for now.
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Well here we area few weeks on. The Varnish job is alldone now & now started refitting all the stuff.
I was thinking of doing something like Bob has done by putting a inboard music system. However I still have not worked out how old this type of boat would be. Has any one got any clues 40, 50, 60, ???
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some update pics
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The Boat is comming along. I have had it in the water twice now. It now has spray rails & a new motor. The cabin side walls are being repainted cream. Work is also underway to fit out the wheel house insdes. Lots to do still. :-))